{"abstract":"The query violates its result contract: deduplicates the left branch before bag union.","category":"Relational algebra","checks":8,"contract":"Return all k occurrences from a followed by all from b as an unordered bag. Inputs are finite relations a=rows and b=refs with columns (id,k,v,w,flag,parent). IDs are unique within each relation, None is SQL NULL, keys are ASCII strings or None, and other values are integers or None. Return an unordered result bag as lists sorted by repr, preserving multiplicity unless explicitly distinct.","evaluation_group":"xs-union-bag","failed_approach":"The alternative query still fails because it deduplicates the right branch before bag union. Attempted SQL: SELECT k FROM a UNION ALL SELECT DISTINCT k FROM b","family":"xs-union-bag-left-distinct","id":"FA-1876","implementations":{"attempt":{"sha256":"242297fae2a4c93d16c7b25e88daa9b86bf074e0adc0d612b56ae8bac9e0e603","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport sqlite3\nN = 1\nobservations = []\ndef solve(rows, refs):\n    db = sqlite3.connect(':memory:')\n    try:\n        for name, records in [('a', rows), ('b', refs)]:\n            db.execute('CREATE TABLE ' + name + ' (id INTEGER PRIMARY KEY, k TEXT, v INTEGER, w INTEGER, flag INTEGER, parent INTEGER)')\n            db.executemany('INSERT INTO ' + name + ' VALUES (?,?,?,?,?,?)', records)\n        return sorted([list(row) for row in db.execute('SELECT k FROM a UNION ALL SELECT DISTINCT k FROM b')], key=repr)\n    finally:\n        db.close()\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nif N == 1:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[11, 'a', None, 8, None, None], [21, 'a', 0, 3, 0, 11], [31, 'a', 2, 1, 1, 21], [41, 'a', 2, 2, 2, 901], [51, 'a', -1, 4, -1, 31], [61, 'a', 3, 1, 1, 41], [71, 'b', -2, 2, 0, 11], [81, 'b', 2, 8, 1, 21], [91, 'b', None, 4, None, None], [101, None, None, 0, 1, 901], [111, None, 0, 5, 0, 11], [121, None, None, 7, None, 21], [131, 'c', None, 6, None, 31], [141, 'd', -1, 1, 0, 41], [151, 'A', 2, 2, 1, 51], [161, ' a ', 2, 8, 1, None], [171, '', None, 2, 0, None], [181, 'a', 2, 8, 1, 11], [191, 'd', 1, 3, 0, 41], [201, 'd', -1, 0, -1, 21]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[11, 'a', None, 0, 1, None], [21, 'a', 2, 2, 0, None], [31, 'a', 2, 3, 2, None], [41, 'a', 3, 4, None, None], [51, 'b', -2, 2, 1, None], [61, 'b', 0, 8, -1, None], [71, None, None, 2, 1, None], [81, None, 0, 5, None, None], [91, 'z', 3, 2, 0, None], [101, 'z', 3, 2, 1, None], [111, 'A', 2, 1, 1, None], [121, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[11, 'a', None, 8, None, None], [21, 'a', 0, 3, 0, 11], [31, 'a', 2, 1, 1, 21], [41, 'a', 2, 2, 2, 901], [51, 'a', -1, 4, -1, 31], [61, 'a', 3, 1, 1, 41], [71, 'b', -2, 2, 0, 11], [81, 'b', 2, 8, 1, 21], [91, 'b', None, 4, None, None], [101, None, None, 0, 1, 901], [111, None, 0, 5, 0, 11], [121, None, None, 7, None, 21], [131, 'c', None, 6, None, 31], [141, 'd', -1, 1, 0, 41], [151, 'A', 2, 2, 1, 51], [161, ' a ', 2, 8, 1, None], [171, '', None, 2, 0, None], [181, 'a', 2, 8, 1, 11], [191, 'd', 1, 3, 0, 41], [201, 'd', -1, 0, -1, 21]], [[11, 'a', None, 0, 1, None], [21, 'a', 2, 2, 0, None], [31, 'a', 2, 3, 2, None], [41, 'a', 3, 4, None, None], [51, 'b', -2, 2, 1, None], [61, 'b', 0, 8, -1, None], [71, None, None, 2, 1, None], [81, None, 0, 5, None, None], [91, 'z', 3, 2, 0, None], [101, 'z', 3, 2, 1, None], [111, 'A', 2, 1, 1, None], [121, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[11, None, None, 3, None, None], [21, None, None, 4, None, None], [31, 'x', None, 5, None, None]], [[11, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[11, 'a', 0, 9, 0, 11]], [[11, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[11, 'n', -2, 4, -1, 11], [21, 'n', None, 2, 0, 21], [31, 'n', -1, 0, 2, None]], [[11, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[11, 'p', 2, 1, 1, 11], [21, 'p', 2, 2, 1, 11], [31, 'p', 3, 0, 1, 11], [41, 'p', None, 1, 0, None]], [[11, 'p', 2, 1, 1, None], [21, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 2:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[12, 'a', None, 8, None, None], [22, 'a', 0, 3, 0, 12], [32, 'a', 2, 1, 1, 22], [42, 'a', 2, 2, 2, 902], [52, 'a', -1, 4, -1, 32], [62, 'a', 3, 1, 1, 42], [72, 'b', -2, 2, 0, 12], [82, 'b', 2, 8, 1, 22], [92, 'b', None, 4, None, None], [102, None, None, 0, 1, 902], [112, None, 0, 5, 0, 12], [122, None, None, 7, None, 22], [132, 'c', None, 6, None, 32], [142, 'd', -1, 1, 0, 42], [152, 'A', 2, 2, 1, 52], [162, ' a ', 2, 8, 1, None], [172, '', None, 2, 0, None], [182, 'a', 2, 8, 1, 12], [192, 'd', 1, 3, 0, 42], [202, 'd', -1, 0, -1, 22]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[12, 'a', None, 0, 1, None], [22, 'a', 2, 2, 0, None], [32, 'a', 2, 3, 2, None], [42, 'a', 3, 4, None, None], [52, 'b', -2, 2, 1, None], [62, 'b', 0, 8, -1, None], [72, None, None, 2, 1, None], [82, None, 0, 5, None, None], [92, 'z', 3, 2, 0, None], [102, 'z', 3, 2, 1, None], [112, 'A', 2, 1, 1, None], [122, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[12, 'a', None, 8, None, None], [22, 'a', 0, 3, 0, 12], [32, 'a', 2, 1, 1, 22], [42, 'a', 2, 2, 2, 902], [52, 'a', -1, 4, -1, 32], [62, 'a', 3, 1, 1, 42], [72, 'b', -2, 2, 0, 12], [82, 'b', 2, 8, 1, 22], [92, 'b', None, 4, None, None], [102, None, None, 0, 1, 902], [112, None, 0, 5, 0, 12], [122, None, None, 7, None, 22], [132, 'c', None, 6, None, 32], [142, 'd', -1, 1, 0, 42], [152, 'A', 2, 2, 1, 52], [162, ' a ', 2, 8, 1, None], [172, '', None, 2, 0, None], [182, 'a', 2, 8, 1, 12], [192, 'd', 1, 3, 0, 42], [202, 'd', -1, 0, -1, 22]], [[12, 'a', None, 0, 1, None], [22, 'a', 2, 2, 0, None], [32, 'a', 2, 3, 2, None], [42, 'a', 3, 4, None, None], [52, 'b', -2, 2, 1, None], [62, 'b', 0, 8, -1, None], [72, None, None, 2, 1, None], [82, None, 0, 5, None, None], [92, 'z', 3, 2, 0, None], [102, 'z', 3, 2, 1, None], [112, 'A', 2, 1, 1, None], [122, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[12, None, None, 3, None, None], [22, None, None, 4, None, None], [32, 'x', None, 5, None, None]], [[12, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[12, 'a', 0, 9, 0, 12]], [[12, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[12, 'n', -2, 4, -1, 12], [22, 'n', None, 2, 0, 22], [32, 'n', -1, 0, 2, None]], [[12, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[12, 'p', 2, 1, 1, 12], [22, 'p', 2, 2, 1, 12], [32, 'p', 3, 0, 1, 12], [42, 'p', None, 1, 0, None]], [[12, 'p', 2, 1, 1, None], [22, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 3:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[13, 'a', None, 8, None, None], [23, 'a', 0, 3, 0, 13], [33, 'a', 2, 1, 1, 23], [43, 'a', 2, 2, 2, 903], [53, 'a', -1, 4, -1, 33], [63, 'a', 3, 1, 1, 43], [73, 'b', -2, 2, 0, 13], [83, 'b', 2, 8, 1, 23], [93, 'b', None, 4, None, None], [103, None, None, 0, 1, 903], [113, None, 0, 5, 0, 13], [123, None, None, 7, None, 23], [133, 'c', None, 6, None, 33], [143, 'd', -1, 1, 0, 43], [153, 'A', 2, 2, 1, 53], [163, ' a ', 2, 8, 1, None], [173, '', None, 2, 0, None], [183, 'a', 2, 8, 1, 13], [193, 'd', 1, 3, 0, 43], [203, 'd', -1, 0, -1, 23]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[13, 'a', None, 0, 1, None], [23, 'a', 2, 2, 0, None], [33, 'a', 2, 3, 2, None], [43, 'a', 3, 4, None, None], [53, 'b', -2, 2, 1, None], [63, 'b', 0, 8, -1, None], [73, None, None, 2, 1, None], [83, None, 0, 5, None, None], [93, 'z', 3, 2, 0, None], [103, 'z', 3, 2, 1, None], [113, 'A', 2, 1, 1, None], [123, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[13, 'a', None, 8, None, None], [23, 'a', 0, 3, 0, 13], [33, 'a', 2, 1, 1, 23], [43, 'a', 2, 2, 2, 903], [53, 'a', -1, 4, -1, 33], [63, 'a', 3, 1, 1, 43], [73, 'b', -2, 2, 0, 13], [83, 'b', 2, 8, 1, 23], [93, 'b', None, 4, None, None], [103, None, None, 0, 1, 903], [113, None, 0, 5, 0, 13], [123, None, None, 7, None, 23], [133, 'c', None, 6, None, 33], [143, 'd', -1, 1, 0, 43], [153, 'A', 2, 2, 1, 53], [163, ' a ', 2, 8, 1, None], [173, '', None, 2, 0, None], [183, 'a', 2, 8, 1, 13], [193, 'd', 1, 3, 0, 43], [203, 'd', -1, 0, -1, 23]], [[13, 'a', None, 0, 1, None], [23, 'a', 2, 2, 0, None], [33, 'a', 2, 3, 2, None], [43, 'a', 3, 4, None, None], [53, 'b', -2, 2, 1, None], [63, 'b', 0, 8, -1, None], [73, None, None, 2, 1, None], [83, None, 0, 5, None, None], [93, 'z', 3, 2, 0, None], [103, 'z', 3, 2, 1, None], [113, 'A', 2, 1, 1, None], [123, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[13, None, None, 3, None, None], [23, None, None, 4, None, None], [33, 'x', None, 5, None, None]], [[13, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[13, 'a', 0, 9, 0, 13]], [[13, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[13, 'n', -2, 4, -1, 13], [23, 'n', None, 2, 0, 23], [33, 'n', -1, 0, 2, None]], [[13, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[13, 'p', 2, 1, 1, 13], [23, 'p', 2, 2, 1, 13], [33, 'p', 3, 0, 1, 13], [43, 'p', None, 1, 0, None]], [[13, 'p', 2, 1, 1, None], [23, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 4:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[14, 'a', None, 8, None, None], [24, 'a', 0, 3, 0, 14], [34, 'a', 2, 1, 1, 24], [44, 'a', 2, 2, 2, 904], [54, 'a', -1, 4, -1, 34], [64, 'a', 3, 1, 1, 44], [74, 'b', -2, 2, 0, 14], [84, 'b', 2, 8, 1, 24], [94, 'b', None, 4, None, None], [104, None, None, 0, 1, 904], [114, None, 0, 5, 0, 14], [124, None, None, 7, None, 24], [134, 'c', None, 6, None, 34], [144, 'd', -1, 1, 0, 44], [154, 'A', 2, 2, 1, 54], [164, ' a ', 2, 8, 1, None], [174, '', None, 2, 0, None], [184, 'a', 2, 8, 1, 14], [194, 'd', 1, 3, 0, 44], [204, 'd', -1, 0, -1, 24]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[14, 'a', None, 0, 1, None], [24, 'a', 2, 2, 0, None], [34, 'a', 2, 3, 2, None], [44, 'a', 3, 4, None, None], [54, 'b', -2, 2, 1, None], [64, 'b', 0, 8, -1, None], [74, None, None, 2, 1, None], [84, None, 0, 5, None, None], [94, 'z', 3, 2, 0, None], [104, 'z', 3, 2, 1, None], [114, 'A', 2, 1, 1, None], [124, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[14, 'a', None, 8, None, None], [24, 'a', 0, 3, 0, 14], [34, 'a', 2, 1, 1, 24], [44, 'a', 2, 2, 2, 904], [54, 'a', -1, 4, -1, 34], [64, 'a', 3, 1, 1, 44], [74, 'b', -2, 2, 0, 14], [84, 'b', 2, 8, 1, 24], [94, 'b', None, 4, None, None], [104, None, None, 0, 1, 904], [114, None, 0, 5, 0, 14], [124, None, None, 7, None, 24], [134, 'c', None, 6, None, 34], [144, 'd', -1, 1, 0, 44], [154, 'A', 2, 2, 1, 54], [164, ' a ', 2, 8, 1, None], [174, '', None, 2, 0, None], [184, 'a', 2, 8, 1, 14], [194, 'd', 1, 3, 0, 44], [204, 'd', -1, 0, -1, 24]], [[14, 'a', None, 0, 1, None], [24, 'a', 2, 2, 0, None], [34, 'a', 2, 3, 2, None], [44, 'a', 3, 4, None, None], [54, 'b', -2, 2, 1, None], [64, 'b', 0, 8, -1, None], [74, None, None, 2, 1, None], [84, None, 0, 5, None, None], [94, 'z', 3, 2, 0, None], [104, 'z', 3, 2, 1, None], [114, 'A', 2, 1, 1, None], [124, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[14, None, None, 3, None, None], [24, None, None, 4, None, None], [34, 'x', None, 5, None, None]], [[14, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[14, 'a', 0, 9, 0, 14]], [[14, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[14, 'n', -2, 4, -1, 14], [24, 'n', None, 2, 0, 24], [34, 'n', -1, 0, 2, None]], [[14, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[14, 'p', 2, 1, 1, 14], [24, 'p', 2, 2, 1, 14], [34, 'p', 3, 0, 1, 14], [44, 'p', None, 1, 0, None]], [[14, 'p', 2, 1, 1, None], [24, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 5:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[15, 'a', None, 8, None, None], [25, 'a', 0, 3, 0, 15], [35, 'a', 2, 1, 1, 25], [45, 'a', 2, 2, 2, 905], [55, 'a', -1, 4, -1, 35], [65, 'a', 3, 1, 1, 45], [75, 'b', -2, 2, 0, 15], [85, 'b', 2, 8, 1, 25], [95, 'b', None, 4, None, None], [105, None, None, 0, 1, 905], [115, None, 0, 5, 0, 15], [125, None, None, 7, None, 25], [135, 'c', None, 6, None, 35], [145, 'd', -1, 1, 0, 45], [155, 'A', 2, 2, 1, 55], [165, ' a ', 2, 8, 1, None], [175, '', None, 2, 0, None], [185, 'a', 2, 8, 1, 15], [195, 'd', 1, 3, 0, 45], [205, 'd', -1, 0, -1, 25]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[15, 'a', None, 0, 1, None], [25, 'a', 2, 2, 0, None], [35, 'a', 2, 3, 2, None], [45, 'a', 3, 4, None, None], [55, 'b', -2, 2, 1, None], [65, 'b', 0, 8, -1, None], [75, None, None, 2, 1, None], [85, None, 0, 5, None, None], [95, 'z', 3, 2, 0, None], [105, 'z', 3, 2, 1, None], [115, 'A', 2, 1, 1, None], [125, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[15, 'a', None, 8, None, None], [25, 'a', 0, 3, 0, 15], [35, 'a', 2, 1, 1, 25], [45, 'a', 2, 2, 2, 905], [55, 'a', -1, 4, -1, 35], [65, 'a', 3, 1, 1, 45], [75, 'b', -2, 2, 0, 15], [85, 'b', 2, 8, 1, 25], [95, 'b', None, 4, None, None], [105, None, None, 0, 1, 905], [115, None, 0, 5, 0, 15], [125, None, None, 7, None, 25], [135, 'c', None, 6, None, 35], [145, 'd', -1, 1, 0, 45], [155, 'A', 2, 2, 1, 55], [165, ' a ', 2, 8, 1, None], [175, '', None, 2, 0, None], [185, 'a', 2, 8, 1, 15], [195, 'd', 1, 3, 0, 45], [205, 'd', -1, 0, -1, 25]], [[15, 'a', None, 0, 1, None], [25, 'a', 2, 2, 0, None], [35, 'a', 2, 3, 2, None], [45, 'a', 3, 4, None, None], [55, 'b', -2, 2, 1, None], [65, 'b', 0, 8, -1, None], [75, None, None, 2, 1, None], [85, None, 0, 5, None, None], [95, 'z', 3, 2, 0, None], [105, 'z', 3, 2, 1, None], [115, 'A', 2, 1, 1, None], [125, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[15, None, None, 3, None, None], [25, None, None, 4, None, None], [35, 'x', None, 5, None, None]], [[15, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[15, 'a', 0, 9, 0, 15]], [[15, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[15, 'n', -2, 4, -1, 15], [25, 'n', None, 2, 0, 25], [35, 'n', -1, 0, 2, None]], [[15, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[15, 'p', 2, 1, 1, 15], [25, 'p', 2, 2, 1, 15], [35, 'p', 3, 0, 1, 15], [45, 'p', None, 1, 0, None]], [[15, 'p', 2, 1, 1, None], [25, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"c7de9b497248ea8b97524702e54f4c9a13eb4a90461ecd5808717752e5315e48","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport sqlite3\nN = 1\nobservations = []\ndef solve(rows, refs):\n    db = sqlite3.connect(':memory:')\n    try:\n        for name, records in [('a', rows), ('b', refs)]:\n            db.execute('CREATE TABLE ' + name + ' (id INTEGER PRIMARY KEY, k TEXT, v INTEGER, w INTEGER, flag INTEGER, parent INTEGER)')\n            db.executemany('INSERT INTO ' + name + ' VALUES (?,?,?,?,?,?)', records)\n        return sorted([list(row) for row in db.execute('SELECT DISTINCT k FROM a UNION ALL SELECT k FROM b')], key=repr)\n    finally:\n        db.close()\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nif N == 1:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[11, 'a', None, 8, None, None], [21, 'a', 0, 3, 0, 11], [31, 'a', 2, 1, 1, 21], [41, 'a', 2, 2, 2, 901], [51, 'a', -1, 4, -1, 31], [61, 'a', 3, 1, 1, 41], [71, 'b', -2, 2, 0, 11], [81, 'b', 2, 8, 1, 21], [91, 'b', None, 4, None, None], [101, None, None, 0, 1, 901], [111, None, 0, 5, 0, 11], [121, None, None, 7, None, 21], [131, 'c', None, 6, None, 31], [141, 'd', -1, 1, 0, 41], [151, 'A', 2, 2, 1, 51], [161, ' a ', 2, 8, 1, None], [171, '', None, 2, 0, None], [181, 'a', 2, 8, 1, 11], [191, 'd', 1, 3, 0, 41], [201, 'd', -1, 0, -1, 21]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[11, 'a', None, 0, 1, None], [21, 'a', 2, 2, 0, None], [31, 'a', 2, 3, 2, None], [41, 'a', 3, 4, None, None], [51, 'b', -2, 2, 1, None], [61, 'b', 0, 8, -1, None], [71, None, None, 2, 1, None], [81, None, 0, 5, None, None], [91, 'z', 3, 2, 0, None], [101, 'z', 3, 2, 1, None], [111, 'A', 2, 1, 1, None], [121, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[11, 'a', None, 8, None, None], [21, 'a', 0, 3, 0, 11], [31, 'a', 2, 1, 1, 21], [41, 'a', 2, 2, 2, 901], [51, 'a', -1, 4, -1, 31], [61, 'a', 3, 1, 1, 41], [71, 'b', -2, 2, 0, 11], [81, 'b', 2, 8, 1, 21], [91, 'b', None, 4, None, None], [101, None, None, 0, 1, 901], [111, None, 0, 5, 0, 11], [121, None, None, 7, None, 21], [131, 'c', None, 6, None, 31], [141, 'd', -1, 1, 0, 41], [151, 'A', 2, 2, 1, 51], [161, ' a ', 2, 8, 1, None], [171, '', None, 2, 0, None], [181, 'a', 2, 8, 1, 11], [191, 'd', 1, 3, 0, 41], [201, 'd', -1, 0, -1, 21]], [[11, 'a', None, 0, 1, None], [21, 'a', 2, 2, 0, None], [31, 'a', 2, 3, 2, None], [41, 'a', 3, 4, None, None], [51, 'b', -2, 2, 1, None], [61, 'b', 0, 8, -1, None], [71, None, None, 2, 1, None], [81, None, 0, 5, None, None], [91, 'z', 3, 2, 0, None], [101, 'z', 3, 2, 1, None], [111, 'A', 2, 1, 1, None], [121, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[11, None, None, 3, None, None], [21, None, None, 4, None, None], [31, 'x', None, 5, None, None]], [[11, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[11, 'a', 0, 9, 0, 11]], [[11, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[11, 'n', -2, 4, -1, 11], [21, 'n', None, 2, 0, 21], [31, 'n', -1, 0, 2, None]], [[11, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[11, 'p', 2, 1, 1, 11], [21, 'p', 2, 2, 1, 11], [31, 'p', 3, 0, 1, 11], [41, 'p', None, 1, 0, None]], [[11, 'p', 2, 1, 1, None], [21, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 2:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[12, 'a', None, 8, None, None], [22, 'a', 0, 3, 0, 12], [32, 'a', 2, 1, 1, 22], [42, 'a', 2, 2, 2, 902], [52, 'a', -1, 4, -1, 32], [62, 'a', 3, 1, 1, 42], [72, 'b', -2, 2, 0, 12], [82, 'b', 2, 8, 1, 22], [92, 'b', None, 4, None, None], [102, None, None, 0, 1, 902], [112, None, 0, 5, 0, 12], [122, None, None, 7, None, 22], [132, 'c', None, 6, None, 32], [142, 'd', -1, 1, 0, 42], [152, 'A', 2, 2, 1, 52], [162, ' a ', 2, 8, 1, None], [172, '', None, 2, 0, None], [182, 'a', 2, 8, 1, 12], [192, 'd', 1, 3, 0, 42], [202, 'd', -1, 0, -1, 22]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[12, 'a', None, 0, 1, None], [22, 'a', 2, 2, 0, None], [32, 'a', 2, 3, 2, None], [42, 'a', 3, 4, None, None], [52, 'b', -2, 2, 1, None], [62, 'b', 0, 8, -1, None], [72, None, None, 2, 1, None], [82, None, 0, 5, None, None], [92, 'z', 3, 2, 0, None], [102, 'z', 3, 2, 1, None], [112, 'A', 2, 1, 1, None], [122, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[12, 'a', None, 8, None, None], [22, 'a', 0, 3, 0, 12], [32, 'a', 2, 1, 1, 22], [42, 'a', 2, 2, 2, 902], [52, 'a', -1, 4, -1, 32], [62, 'a', 3, 1, 1, 42], [72, 'b', -2, 2, 0, 12], [82, 'b', 2, 8, 1, 22], [92, 'b', None, 4, None, None], [102, None, None, 0, 1, 902], [112, None, 0, 5, 0, 12], [122, None, None, 7, None, 22], [132, 'c', None, 6, None, 32], [142, 'd', -1, 1, 0, 42], [152, 'A', 2, 2, 1, 52], [162, ' a ', 2, 8, 1, None], [172, '', None, 2, 0, None], [182, 'a', 2, 8, 1, 12], [192, 'd', 1, 3, 0, 42], [202, 'd', -1, 0, -1, 22]], [[12, 'a', None, 0, 1, None], [22, 'a', 2, 2, 0, None], [32, 'a', 2, 3, 2, None], [42, 'a', 3, 4, None, None], [52, 'b', -2, 2, 1, None], [62, 'b', 0, 8, -1, None], [72, None, None, 2, 1, None], [82, None, 0, 5, None, None], [92, 'z', 3, 2, 0, None], [102, 'z', 3, 2, 1, None], [112, 'A', 2, 1, 1, None], [122, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[12, None, None, 3, None, None], [22, None, None, 4, None, None], [32, 'x', None, 5, None, None]], [[12, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[12, 'a', 0, 9, 0, 12]], [[12, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[12, 'n', -2, 4, -1, 12], [22, 'n', None, 2, 0, 22], [32, 'n', -1, 0, 2, None]], [[12, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[12, 'p', 2, 1, 1, 12], [22, 'p', 2, 2, 1, 12], [32, 'p', 3, 0, 1, 12], [42, 'p', None, 1, 0, None]], [[12, 'p', 2, 1, 1, None], [22, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 3:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[13, 'a', None, 8, None, None], [23, 'a', 0, 3, 0, 13], [33, 'a', 2, 1, 1, 23], [43, 'a', 2, 2, 2, 903], [53, 'a', -1, 4, -1, 33], [63, 'a', 3, 1, 1, 43], [73, 'b', -2, 2, 0, 13], [83, 'b', 2, 8, 1, 23], [93, 'b', None, 4, None, None], [103, None, None, 0, 1, 903], [113, None, 0, 5, 0, 13], [123, None, None, 7, None, 23], [133, 'c', None, 6, None, 33], [143, 'd', -1, 1, 0, 43], [153, 'A', 2, 2, 1, 53], [163, ' a ', 2, 8, 1, None], [173, '', None, 2, 0, None], [183, 'a', 2, 8, 1, 13], [193, 'd', 1, 3, 0, 43], [203, 'd', -1, 0, -1, 23]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[13, 'a', None, 0, 1, None], [23, 'a', 2, 2, 0, None], [33, 'a', 2, 3, 2, None], [43, 'a', 3, 4, None, None], [53, 'b', -2, 2, 1, None], [63, 'b', 0, 8, -1, None], [73, None, None, 2, 1, None], [83, None, 0, 5, None, None], [93, 'z', 3, 2, 0, None], [103, 'z', 3, 2, 1, None], [113, 'A', 2, 1, 1, None], [123, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[13, 'a', None, 8, None, None], [23, 'a', 0, 3, 0, 13], [33, 'a', 2, 1, 1, 23], [43, 'a', 2, 2, 2, 903], [53, 'a', -1, 4, -1, 33], [63, 'a', 3, 1, 1, 43], [73, 'b', -2, 2, 0, 13], [83, 'b', 2, 8, 1, 23], [93, 'b', None, 4, None, None], [103, None, None, 0, 1, 903], [113, None, 0, 5, 0, 13], [123, None, None, 7, None, 23], [133, 'c', None, 6, None, 33], [143, 'd', -1, 1, 0, 43], [153, 'A', 2, 2, 1, 53], [163, ' a ', 2, 8, 1, None], [173, '', None, 2, 0, None], [183, 'a', 2, 8, 1, 13], [193, 'd', 1, 3, 0, 43], [203, 'd', -1, 0, -1, 23]], [[13, 'a', None, 0, 1, None], [23, 'a', 2, 2, 0, None], [33, 'a', 2, 3, 2, None], [43, 'a', 3, 4, None, None], [53, 'b', -2, 2, 1, None], [63, 'b', 0, 8, -1, None], [73, None, None, 2, 1, None], [83, None, 0, 5, None, None], [93, 'z', 3, 2, 0, None], [103, 'z', 3, 2, 1, None], [113, 'A', 2, 1, 1, None], [123, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[13, None, None, 3, None, None], [23, None, None, 4, None, None], [33, 'x', None, 5, None, None]], [[13, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[13, 'a', 0, 9, 0, 13]], [[13, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[13, 'n', -2, 4, -1, 13], [23, 'n', None, 2, 0, 23], [33, 'n', -1, 0, 2, None]], [[13, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[13, 'p', 2, 1, 1, 13], [23, 'p', 2, 2, 1, 13], [33, 'p', 3, 0, 1, 13], [43, 'p', None, 1, 0, None]], [[13, 'p', 2, 1, 1, None], [23, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 4:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[14, 'a', None, 8, None, None], [24, 'a', 0, 3, 0, 14], [34, 'a', 2, 1, 1, 24], [44, 'a', 2, 2, 2, 904], [54, 'a', -1, 4, -1, 34], [64, 'a', 3, 1, 1, 44], [74, 'b', -2, 2, 0, 14], [84, 'b', 2, 8, 1, 24], [94, 'b', None, 4, None, None], [104, None, None, 0, 1, 904], [114, None, 0, 5, 0, 14], [124, None, None, 7, None, 24], [134, 'c', None, 6, None, 34], [144, 'd', -1, 1, 0, 44], [154, 'A', 2, 2, 1, 54], [164, ' a ', 2, 8, 1, None], [174, '', None, 2, 0, None], [184, 'a', 2, 8, 1, 14], [194, 'd', 1, 3, 0, 44], [204, 'd', -1, 0, -1, 24]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[14, 'a', None, 0, 1, None], [24, 'a', 2, 2, 0, None], [34, 'a', 2, 3, 2, None], [44, 'a', 3, 4, None, None], [54, 'b', -2, 2, 1, None], [64, 'b', 0, 8, -1, None], [74, None, None, 2, 1, None], [84, None, 0, 5, None, None], [94, 'z', 3, 2, 0, None], [104, 'z', 3, 2, 1, None], [114, 'A', 2, 1, 1, None], [124, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[14, 'a', None, 8, None, None], [24, 'a', 0, 3, 0, 14], [34, 'a', 2, 1, 1, 24], [44, 'a', 2, 2, 2, 904], [54, 'a', -1, 4, -1, 34], [64, 'a', 3, 1, 1, 44], [74, 'b', -2, 2, 0, 14], [84, 'b', 2, 8, 1, 24], [94, 'b', None, 4, None, None], [104, None, None, 0, 1, 904], [114, None, 0, 5, 0, 14], [124, None, None, 7, None, 24], [134, 'c', None, 6, None, 34], [144, 'd', -1, 1, 0, 44], [154, 'A', 2, 2, 1, 54], [164, ' a ', 2, 8, 1, None], [174, '', None, 2, 0, None], [184, 'a', 2, 8, 1, 14], [194, 'd', 1, 3, 0, 44], [204, 'd', -1, 0, -1, 24]], [[14, 'a', None, 0, 1, None], [24, 'a', 2, 2, 0, None], [34, 'a', 2, 3, 2, None], [44, 'a', 3, 4, None, None], [54, 'b', -2, 2, 1, None], [64, 'b', 0, 8, -1, None], [74, None, None, 2, 1, None], [84, None, 0, 5, None, None], [94, 'z', 3, 2, 0, None], [104, 'z', 3, 2, 1, None], [114, 'A', 2, 1, 1, None], [124, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[14, None, None, 3, None, None], [24, None, None, 4, None, None], [34, 'x', None, 5, None, None]], [[14, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[14, 'a', 0, 9, 0, 14]], [[14, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[14, 'n', -2, 4, -1, 14], [24, 'n', None, 2, 0, 24], [34, 'n', -1, 0, 2, None]], [[14, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[14, 'p', 2, 1, 1, 14], [24, 'p', 2, 2, 1, 14], [34, 'p', 3, 0, 1, 14], [44, 'p', None, 1, 0, None]], [[14, 'p', 2, 1, 1, None], [24, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 5:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[15, 'a', None, 8, None, None], [25, 'a', 0, 3, 0, 15], [35, 'a', 2, 1, 1, 25], [45, 'a', 2, 2, 2, 905], [55, 'a', -1, 4, -1, 35], [65, 'a', 3, 1, 1, 45], [75, 'b', -2, 2, 0, 15], [85, 'b', 2, 8, 1, 25], [95, 'b', None, 4, None, None], [105, None, None, 0, 1, 905], [115, None, 0, 5, 0, 15], [125, None, None, 7, None, 25], [135, 'c', None, 6, None, 35], [145, 'd', -1, 1, 0, 45], [155, 'A', 2, 2, 1, 55], [165, ' a ', 2, 8, 1, None], [175, '', None, 2, 0, None], [185, 'a', 2, 8, 1, 15], [195, 'd', 1, 3, 0, 45], [205, 'd', -1, 0, -1, 25]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[15, 'a', None, 0, 1, None], [25, 'a', 2, 2, 0, None], [35, 'a', 2, 3, 2, None], [45, 'a', 3, 4, None, None], [55, 'b', -2, 2, 1, None], [65, 'b', 0, 8, -1, None], [75, None, None, 2, 1, None], [85, None, 0, 5, None, None], [95, 'z', 3, 2, 0, None], [105, 'z', 3, 2, 1, None], [115, 'A', 2, 1, 1, None], [125, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[15, 'a', None, 8, None, None], [25, 'a', 0, 3, 0, 15], [35, 'a', 2, 1, 1, 25], [45, 'a', 2, 2, 2, 905], [55, 'a', -1, 4, -1, 35], [65, 'a', 3, 1, 1, 45], [75, 'b', -2, 2, 0, 15], [85, 'b', 2, 8, 1, 25], [95, 'b', None, 4, None, None], [105, None, None, 0, 1, 905], [115, None, 0, 5, 0, 15], [125, None, None, 7, None, 25], [135, 'c', None, 6, None, 35], [145, 'd', -1, 1, 0, 45], [155, 'A', 2, 2, 1, 55], [165, ' a ', 2, 8, 1, None], [175, '', None, 2, 0, None], [185, 'a', 2, 8, 1, 15], [195, 'd', 1, 3, 0, 45], [205, 'd', -1, 0, -1, 25]], [[15, 'a', None, 0, 1, None], [25, 'a', 2, 2, 0, None], [35, 'a', 2, 3, 2, None], [45, 'a', 3, 4, None, None], [55, 'b', -2, 2, 1, None], [65, 'b', 0, 8, -1, None], [75, None, None, 2, 1, None], [85, None, 0, 5, None, None], [95, 'z', 3, 2, 0, None], [105, 'z', 3, 2, 1, None], [115, 'A', 2, 1, 1, None], [125, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[15, None, None, 3, None, None], [25, None, None, 4, None, None], [35, 'x', None, 5, None, None]], [[15, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[15, 'a', 0, 9, 0, 15]], [[15, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[15, 'n', -2, 4, -1, 15], [25, 'n', None, 2, 0, 25], [35, 'n', -1, 0, 2, None]], [[15, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[15, 'p', 2, 1, 1, 15], [25, 'p', 2, 2, 1, 15], [35, 'p', 3, 0, 1, 15], [45, 'p', None, 1, 0, None]], [[15, 'p', 2, 1, 1, None], [25, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"fixed":{"sha256":"c2b1dad1579db910669f1d7890f45773878f9ec3931fe498a675b1e2d6c0c25c","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport sqlite3\nN = 1\nobservations = []\ndef solve(rows, refs):\n    db = sqlite3.connect(':memory:')\n    try:\n        for name, records in [('a', rows), ('b', refs)]:\n            db.execute('CREATE TABLE ' + name + ' (id INTEGER PRIMARY KEY, k TEXT, v INTEGER, w INTEGER, flag INTEGER, parent INTEGER)')\n            db.executemany('INSERT INTO ' + name + ' VALUES (?,?,?,?,?,?)', records)\n        return sorted([list(row) for row in db.execute('SELECT k FROM a UNION ALL SELECT k FROM b')], key=repr)\n    finally:\n        db.close()\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nif N == 1:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[11, 'a', None, 8, None, None], [21, 'a', 0, 3, 0, 11], [31, 'a', 2, 1, 1, 21], [41, 'a', 2, 2, 2, 901], [51, 'a', -1, 4, -1, 31], [61, 'a', 3, 1, 1, 41], [71, 'b', -2, 2, 0, 11], [81, 'b', 2, 8, 1, 21], [91, 'b', None, 4, None, None], [101, None, None, 0, 1, 901], [111, None, 0, 5, 0, 11], [121, None, None, 7, None, 21], [131, 'c', None, 6, None, 31], [141, 'd', -1, 1, 0, 41], [151, 'A', 2, 2, 1, 51], [161, ' a ', 2, 8, 1, None], [171, '', None, 2, 0, None], [181, 'a', 2, 8, 1, 11], [191, 'd', 1, 3, 0, 41], [201, 'd', -1, 0, -1, 21]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[11, 'a', None, 0, 1, None], [21, 'a', 2, 2, 0, None], [31, 'a', 2, 3, 2, None], [41, 'a', 3, 4, None, None], [51, 'b', -2, 2, 1, None], [61, 'b', 0, 8, -1, None], [71, None, None, 2, 1, None], [81, None, 0, 5, None, None], [91, 'z', 3, 2, 0, None], [101, 'z', 3, 2, 1, None], [111, 'A', 2, 1, 1, None], [121, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[11, 'a', None, 8, None, None], [21, 'a', 0, 3, 0, 11], [31, 'a', 2, 1, 1, 21], [41, 'a', 2, 2, 2, 901], [51, 'a', -1, 4, -1, 31], [61, 'a', 3, 1, 1, 41], [71, 'b', -2, 2, 0, 11], [81, 'b', 2, 8, 1, 21], [91, 'b', None, 4, None, None], [101, None, None, 0, 1, 901], [111, None, 0, 5, 0, 11], [121, None, None, 7, None, 21], [131, 'c', None, 6, None, 31], [141, 'd', -1, 1, 0, 41], [151, 'A', 2, 2, 1, 51], [161, ' a ', 2, 8, 1, None], [171, '', None, 2, 0, None], [181, 'a', 2, 8, 1, 11], [191, 'd', 1, 3, 0, 41], [201, 'd', -1, 0, -1, 21]], [[11, 'a', None, 0, 1, None], [21, 'a', 2, 2, 0, None], [31, 'a', 2, 3, 2, None], [41, 'a', 3, 4, None, None], [51, 'b', -2, 2, 1, None], [61, 'b', 0, 8, -1, None], [71, None, None, 2, 1, None], [81, None, 0, 5, None, None], [91, 'z', 3, 2, 0, None], [101, 'z', 3, 2, 1, None], [111, 'A', 2, 1, 1, None], [121, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[11, None, None, 3, None, None], [21, None, None, 4, None, None], [31, 'x', None, 5, None, None]], [[11, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[11, 'a', 0, 9, 0, 11]], [[11, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[11, 'n', -2, 4, -1, 11], [21, 'n', None, 2, 0, 21], [31, 'n', -1, 0, 2, None]], [[11, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[11, 'p', 2, 1, 1, 11], [21, 'p', 2, 2, 1, 11], [31, 'p', 3, 0, 1, 11], [41, 'p', None, 1, 0, None]], [[11, 'p', 2, 1, 1, None], [21, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 2:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[12, 'a', None, 8, None, None], [22, 'a', 0, 3, 0, 12], [32, 'a', 2, 1, 1, 22], [42, 'a', 2, 2, 2, 902], [52, 'a', -1, 4, -1, 32], [62, 'a', 3, 1, 1, 42], [72, 'b', -2, 2, 0, 12], [82, 'b', 2, 8, 1, 22], [92, 'b', None, 4, None, None], [102, None, None, 0, 1, 902], [112, None, 0, 5, 0, 12], [122, None, None, 7, None, 22], [132, 'c', None, 6, None, 32], [142, 'd', -1, 1, 0, 42], [152, 'A', 2, 2, 1, 52], [162, ' a ', 2, 8, 1, None], [172, '', None, 2, 0, None], [182, 'a', 2, 8, 1, 12], [192, 'd', 1, 3, 0, 42], [202, 'd', -1, 0, -1, 22]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[12, 'a', None, 0, 1, None], [22, 'a', 2, 2, 0, None], [32, 'a', 2, 3, 2, None], [42, 'a', 3, 4, None, None], [52, 'b', -2, 2, 1, None], [62, 'b', 0, 8, -1, None], [72, None, None, 2, 1, None], [82, None, 0, 5, None, None], [92, 'z', 3, 2, 0, None], [102, 'z', 3, 2, 1, None], [112, 'A', 2, 1, 1, None], [122, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[12, 'a', None, 8, None, None], [22, 'a', 0, 3, 0, 12], [32, 'a', 2, 1, 1, 22], [42, 'a', 2, 2, 2, 902], [52, 'a', -1, 4, -1, 32], [62, 'a', 3, 1, 1, 42], [72, 'b', -2, 2, 0, 12], [82, 'b', 2, 8, 1, 22], [92, 'b', None, 4, None, None], [102, None, None, 0, 1, 902], [112, None, 0, 5, 0, 12], [122, None, None, 7, None, 22], [132, 'c', None, 6, None, 32], [142, 'd', -1, 1, 0, 42], [152, 'A', 2, 2, 1, 52], [162, ' a ', 2, 8, 1, None], [172, '', None, 2, 0, None], [182, 'a', 2, 8, 1, 12], [192, 'd', 1, 3, 0, 42], [202, 'd', -1, 0, -1, 22]], [[12, 'a', None, 0, 1, None], [22, 'a', 2, 2, 0, None], [32, 'a', 2, 3, 2, None], [42, 'a', 3, 4, None, None], [52, 'b', -2, 2, 1, None], [62, 'b', 0, 8, -1, None], [72, None, None, 2, 1, None], [82, None, 0, 5, None, None], [92, 'z', 3, 2, 0, None], [102, 'z', 3, 2, 1, None], [112, 'A', 2, 1, 1, None], [122, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[12, None, None, 3, None, None], [22, None, None, 4, None, None], [32, 'x', None, 5, None, None]], [[12, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[12, 'a', 0, 9, 0, 12]], [[12, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[12, 'n', -2, 4, -1, 12], [22, 'n', None, 2, 0, 22], [32, 'n', -1, 0, 2, None]], [[12, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[12, 'p', 2, 1, 1, 12], [22, 'p', 2, 2, 1, 12], [32, 'p', 3, 0, 1, 12], [42, 'p', None, 1, 0, None]], [[12, 'p', 2, 1, 1, None], [22, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 3:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[13, 'a', None, 8, None, None], [23, 'a', 0, 3, 0, 13], [33, 'a', 2, 1, 1, 23], [43, 'a', 2, 2, 2, 903], [53, 'a', -1, 4, -1, 33], [63, 'a', 3, 1, 1, 43], [73, 'b', -2, 2, 0, 13], [83, 'b', 2, 8, 1, 23], [93, 'b', None, 4, None, None], [103, None, None, 0, 1, 903], [113, None, 0, 5, 0, 13], [123, None, None, 7, None, 23], [133, 'c', None, 6, None, 33], [143, 'd', -1, 1, 0, 43], [153, 'A', 2, 2, 1, 53], [163, ' a ', 2, 8, 1, None], [173, '', None, 2, 0, None], [183, 'a', 2, 8, 1, 13], [193, 'd', 1, 3, 0, 43], [203, 'd', -1, 0, -1, 23]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[13, 'a', None, 0, 1, None], [23, 'a', 2, 2, 0, None], [33, 'a', 2, 3, 2, None], [43, 'a', 3, 4, None, None], [53, 'b', -2, 2, 1, None], [63, 'b', 0, 8, -1, None], [73, None, None, 2, 1, None], [83, None, 0, 5, None, None], [93, 'z', 3, 2, 0, None], [103, 'z', 3, 2, 1, None], [113, 'A', 2, 1, 1, None], [123, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[13, 'a', None, 8, None, None], [23, 'a', 0, 3, 0, 13], [33, 'a', 2, 1, 1, 23], [43, 'a', 2, 2, 2, 903], [53, 'a', -1, 4, -1, 33], [63, 'a', 3, 1, 1, 43], [73, 'b', -2, 2, 0, 13], [83, 'b', 2, 8, 1, 23], [93, 'b', None, 4, None, None], [103, None, None, 0, 1, 903], [113, None, 0, 5, 0, 13], [123, None, None, 7, None, 23], [133, 'c', None, 6, None, 33], [143, 'd', -1, 1, 0, 43], [153, 'A', 2, 2, 1, 53], [163, ' a ', 2, 8, 1, None], [173, '', None, 2, 0, None], [183, 'a', 2, 8, 1, 13], [193, 'd', 1, 3, 0, 43], [203, 'd', -1, 0, -1, 23]], [[13, 'a', None, 0, 1, None], [23, 'a', 2, 2, 0, None], [33, 'a', 2, 3, 2, None], [43, 'a', 3, 4, None, None], [53, 'b', -2, 2, 1, None], [63, 'b', 0, 8, -1, None], [73, None, None, 2, 1, None], [83, None, 0, 5, None, None], [93, 'z', 3, 2, 0, None], [103, 'z', 3, 2, 1, None], [113, 'A', 2, 1, 1, None], [123, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[13, None, None, 3, None, None], [23, None, None, 4, None, None], [33, 'x', None, 5, None, None]], [[13, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[13, 'a', 0, 9, 0, 13]], [[13, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[13, 'n', -2, 4, -1, 13], [23, 'n', None, 2, 0, 23], [33, 'n', -1, 0, 2, None]], [[13, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[13, 'p', 2, 1, 1, 13], [23, 'p', 2, 2, 1, 13], [33, 'p', 3, 0, 1, 13], [43, 'p', None, 1, 0, None]], [[13, 'p', 2, 1, 1, None], [23, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 4:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[14, 'a', None, 8, None, None], [24, 'a', 0, 3, 0, 14], [34, 'a', 2, 1, 1, 24], [44, 'a', 2, 2, 2, 904], [54, 'a', -1, 4, -1, 34], [64, 'a', 3, 1, 1, 44], [74, 'b', -2, 2, 0, 14], [84, 'b', 2, 8, 1, 24], [94, 'b', None, 4, None, None], [104, None, None, 0, 1, 904], [114, None, 0, 5, 0, 14], [124, None, None, 7, None, 24], [134, 'c', None, 6, None, 34], [144, 'd', -1, 1, 0, 44], [154, 'A', 2, 2, 1, 54], [164, ' a ', 2, 8, 1, None], [174, '', None, 2, 0, None], [184, 'a', 2, 8, 1, 14], [194, 'd', 1, 3, 0, 44], [204, 'd', -1, 0, -1, 24]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[14, 'a', None, 0, 1, None], [24, 'a', 2, 2, 0, None], [34, 'a', 2, 3, 2, None], [44, 'a', 3, 4, None, None], [54, 'b', -2, 2, 1, None], [64, 'b', 0, 8, -1, None], [74, None, None, 2, 1, None], [84, None, 0, 5, None, None], [94, 'z', 3, 2, 0, None], [104, 'z', 3, 2, 1, None], [114, 'A', 2, 1, 1, None], [124, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[14, 'a', None, 8, None, None], [24, 'a', 0, 3, 0, 14], [34, 'a', 2, 1, 1, 24], [44, 'a', 2, 2, 2, 904], [54, 'a', -1, 4, -1, 34], [64, 'a', 3, 1, 1, 44], [74, 'b', -2, 2, 0, 14], [84, 'b', 2, 8, 1, 24], [94, 'b', None, 4, None, None], [104, None, None, 0, 1, 904], [114, None, 0, 5, 0, 14], [124, None, None, 7, None, 24], [134, 'c', None, 6, None, 34], [144, 'd', -1, 1, 0, 44], [154, 'A', 2, 2, 1, 54], [164, ' a ', 2, 8, 1, None], [174, '', None, 2, 0, None], [184, 'a', 2, 8, 1, 14], [194, 'd', 1, 3, 0, 44], [204, 'd', -1, 0, -1, 24]], [[14, 'a', None, 0, 1, None], [24, 'a', 2, 2, 0, None], [34, 'a', 2, 3, 2, None], [44, 'a', 3, 4, None, None], [54, 'b', -2, 2, 1, None], [64, 'b', 0, 8, -1, None], [74, None, None, 2, 1, None], [84, None, 0, 5, None, None], [94, 'z', 3, 2, 0, None], [104, 'z', 3, 2, 1, None], [114, 'A', 2, 1, 1, None], [124, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[14, None, None, 3, None, None], [24, None, None, 4, None, None], [34, 'x', None, 5, None, None]], [[14, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[14, 'a', 0, 9, 0, 14]], [[14, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[14, 'n', -2, 4, -1, 14], [24, 'n', None, 2, 0, 24], [34, 'n', -1, 0, 2, None]], [[14, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[14, 'p', 2, 1, 1, 14], [24, 'p', 2, 2, 1, 14], [34, 'p', 3, 0, 1, 14], [44, 'p', None, 1, 0, None]], [[14, 'p', 2, 1, 1, None], [24, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nelif N == 5:\n    check('empty relations', solve([], []), [])\n    check('left facts without references', solve([[15, 'a', None, 8, None, None], [25, 'a', 0, 3, 0, 15], [35, 'a', 2, 1, 1, 25], [45, 'a', 2, 2, 2, 905], [55, 'a', -1, 4, -1, 35], [65, 'a', 3, 1, 1, 45], [75, 'b', -2, 2, 0, 15], [85, 'b', 2, 8, 1, 25], [95, 'b', None, 4, None, None], [105, None, None, 0, 1, 905], [115, None, 0, 5, 0, 15], [125, None, None, 7, None, 25], [135, 'c', None, 6, None, 35], [145, 'd', -1, 1, 0, 45], [155, 'A', 2, 2, 1, 55], [165, ' a ', 2, 8, 1, None], [175, '', None, 2, 0, None], [185, 'a', 2, 8, 1, 15], [195, 'd', 1, 3, 0, 45], [205, 'd', -1, 0, -1, 25]], []), [[' a '], [''], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['c'], ['d'], ['d'], ['d'], [None], [None], [None]])\n    check('references without candidates', solve([], [[15, 'a', None, 0, 1, None], [25, 'a', 2, 2, 0, None], [35, 'a', 2, 3, 2, None], [45, 'a', 3, 4, None, None], [55, 'b', -2, 2, 1, None], [65, 'b', 0, 8, -1, None], [75, None, None, 2, 1, None], [85, None, 0, 5, None, None], [95, 'z', 3, 2, 0, None], [105, 'z', 3, 2, 1, None], [115, 'A', 2, 1, 1, None], [125, 'c', None, 2, 0, None]]), [['A'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['c'], ['z'], ['z'], [None], [None]])\n    check('mixed nullable groups duplicates ties and truth flags', solve([[15, 'a', None, 8, None, None], [25, 'a', 0, 3, 0, 15], [35, 'a', 2, 1, 1, 25], [45, 'a', 2, 2, 2, 905], [55, 'a', -1, 4, -1, 35], [65, 'a', 3, 1, 1, 45], [75, 'b', -2, 2, 0, 15], [85, 'b', 2, 8, 1, 25], [95, 'b', None, 4, None, None], [105, None, None, 0, 1, 905], [115, None, 0, 5, 0, 15], [125, None, None, 7, None, 25], [135, 'c', None, 6, None, 35], [145, 'd', -1, 1, 0, 45], [155, 'A', 2, 2, 1, 55], [165, ' a ', 2, 8, 1, None], [175, '', None, 2, 0, None], [185, 'a', 2, 8, 1, 15], [195, 'd', 1, 3, 0, 45], [205, 'd', -1, 0, -1, 25]], [[15, 'a', None, 0, 1, None], [25, 'a', 2, 2, 0, None], [35, 'a', 2, 3, 2, None], [45, 'a', 3, 4, None, None], [55, 'b', -2, 2, 1, None], [65, 'b', 0, 8, -1, None], [75, None, None, 2, 1, None], [85, None, 0, 5, None, None], [95, 'z', 3, 2, 0, None], [105, 'z', 3, 2, 1, None], [115, 'A', 2, 1, 1, None], [125, 'c', None, 2, 0, None]]), [[' a '], [''], ['A'], ['A'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['a'], ['b'], ['b'], ['b'], ['b'], ['b'], ['c'], ['c'], ['d'], ['d'], ['d'], ['z'], ['z'], [None], [None], [None], [None], [None]])\n    check('unknown-only group with duplicate nullable index keys', solve([[15, None, None, 3, None, None], [25, None, None, 4, None, None], [35, 'x', None, 5, None, None]], [[15, None, None, 2, None, None]]), [['x'], [None], [None], [None]])\n    check('single known zero and matching reference', solve([[15, 'a', 0, 9, 0, 15]], [[15, 'a', 0, 3, 1, None]]), [['a'], ['a']])\n    check('negative-only group and missing measurement', solve([[15, 'n', -2, 4, -1, 15], [25, 'n', None, 2, 0, 25], [35, 'n', -1, 0, 2, None]], [[15, 'n', -2, 1, 1, None]]), [['n'], ['n'], ['n'], ['n']])\n    check('positive-only group with repeated measurements and NULL', solve([[15, 'p', 2, 1, 1, 15], [25, 'p', 2, 2, 1, 15], [35, 'p', 3, 0, 1, 15], [45, 'p', None, 1, 0, None]], [[15, 'p', 2, 1, 1, None], [25, 'p', 2, 1, 1, None]]), [['p'], ['p'], ['p'], ['p'], ['p'], ['p']])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":" This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"xs-union-bag-left-distinct","generated_at":"2026-09-29T14:37:06.672577+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Executes actual in-memory SQLite relational semantics. The fixtures exercise empty inputs, nullable groups, duplicate facts, known zero, negative values, peer ties and partition boundaries. This models the specified query contract, not optimizer performance, disk durability or a complete migration transaction.","repair":"Use the required relational semantics: Return all k occurrences from a followed by all from b as an unordered bag. Correct SQL: SELECT k FROM a UNION ALL SELECT k FROM b","root_cause":"Deduplicates the left branch before bag union. The faulty SQL is: SELECT DISTINCT k FROM a UNION ALL SELECT k FROM b","sha256":"417bb206977e96f036f057d5aeb38714c333a79275dca2fac133f846cae279ef","title":"Union bag: Deduplicates the left branch before bag union · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":114.127,"exit_code":1,"observations":[{"actual":[],"check":"empty relations","expected":[],"passed":true},{"actual":[[" a "],[""],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["c"],["d"],["d"],["d"],[null],[null],[null]],"check":"left facts without references","expected":[[" a "],[""],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["c"],["d"],["d"],["d"],[null],[null],[null]],"passed":true},{"actual":[["A"],["a"],["b"],["c"],["z"],[null]],"check":"references without candidates","expected":[["A"],["a"],["a"],["a"],["a"],["b"],["b"],["c"],["z"],["z"],[null],[null]],"passed":false},{"actual":[[" a "],[""],["A"],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["b"],["c"],["c"],["d"],["d"],["d"],["z"],[null],[null],[null],[null]],"check":"mixed nullable groups duplicates ties and truth flags","expected":[[" a "],[""],["A"],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["b"],["b"],["c"],["c"],["d"],["d"],["d"],["z"],["z"],[null],[null],[null],[null],[null]],"passed":false},{"actual":[["x"],[null],[null],[null]],"check":"unknown-only group with duplicate nullable index keys","expected":[["x"],[null],[null],[null]],"passed":true},{"actual":[["a"],["a"]],"check":"single known zero and matching reference","expected":[["a"],["a"]],"passed":true},{"actual":[["n"],["n"],["n"],["n"]],"check":"negative-only group and missing measurement","expected":[["n"],["n"],["n"],["n"]],"passed":true},{"actual":[["p"],["p"],["p"],["p"],["p"]],"check":"positive-only group with repeated measurements and NULL","expected":[["p"],["p"],["p"],["p"],["p"],["p"]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty relations\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"left facts without references\", \"actual\": [[\" a \"], [\"\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [null], [null], [null]], \"expected\": [[\" a \"], [\"\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [null], [null], [null]], \"passed\": true}, {\"check\": \"references without candidates\", \"actual\": [[\"A\"], [\"a\"], [\"b\"], [\"c\"], [\"z\"], [null]], \"expected\": [[\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"c\"], [\"z\"], [\"z\"], [null], [null]], \"passed\": false}, {\"check\": \"mixed nullable groups duplicates ties and truth flags\", \"actual\": [[\" a \"], [\"\"], [\"A\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [\"z\"], [null], [null], [null], [null]], \"expected\": [[\" a \"], [\"\"], [\"A\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [\"z\"], [\"z\"], [null], [null], [null], [null], [null]], \"passed\": false}, {\"check\": \"unknown-only group with duplicate nullable index keys\", \"actual\": [[\"x\"], [null], [null], [null]], \"expected\": [[\"x\"], [null], [null], [null]], \"passed\": true}, {\"check\": \"single known zero and matching reference\", \"actual\": [[\"a\"], [\"a\"]], \"expected\": [[\"a\"], [\"a\"]], \"passed\": true}, {\"check\": \"negative-only group and missing measurement\", \"actual\": [[\"n\"], [\"n\"], [\"n\"], [\"n\"]], \"expected\": [[\"n\"], [\"n\"], [\"n\"], [\"n\"]], \"passed\": true}, {\"check\": \"positive-only group with repeated measurements and NULL\", \"actual\": [[\"p\"], [\"p\"], [\"p\"], [\"p\"], [\"p\"]], \"expected\": [[\"p\"], [\"p\"], [\"p\"], [\"p\"], [\"p\"], [\"p\"]], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.095,"exit_code":1,"observations":[{"actual":[],"check":"empty relations","expected":[],"passed":true},{"actual":[[" a "],[""],["A"],["a"],["b"],["c"],["d"],[null]],"check":"left facts without references","expected":[[" a "],[""],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["c"],["d"],["d"],["d"],[null],[null],[null]],"passed":false},{"actual":[["A"],["a"],["a"],["a"],["a"],["b"],["b"],["c"],["z"],["z"],[null],[null]],"check":"references without candidates","expected":[["A"],["a"],["a"],["a"],["a"],["b"],["b"],["c"],["z"],["z"],[null],[null]],"passed":true},{"actual":[[" a "],[""],["A"],["A"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["c"],["c"],["d"],["z"],["z"],[null],[null],[null]],"check":"mixed nullable groups duplicates ties and truth flags","expected":[[" a "],[""],["A"],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["b"],["b"],["c"],["c"],["d"],["d"],["d"],["z"],["z"],[null],[null],[null],[null],[null]],"passed":false},{"actual":[["x"],[null],[null]],"check":"unknown-only group with duplicate nullable index keys","expected":[["x"],[null],[null],[null]],"passed":false},{"actual":[["a"],["a"]],"check":"single known zero and matching reference","expected":[["a"],["a"]],"passed":true},{"actual":[["n"],["n"]],"check":"negative-only group and missing measurement","expected":[["n"],["n"],["n"],["n"]],"passed":false},{"actual":[["p"],["p"],["p"]],"check":"positive-only group with repeated measurements and NULL","expected":[["p"],["p"],["p"],["p"],["p"],["p"]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty relations\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"left facts without references\", \"actual\": [[\" a \"], [\"\"], [\"A\"], [\"a\"], [\"b\"], [\"c\"], [\"d\"], [null]], \"expected\": [[\" a \"], [\"\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [null], [null], [null]], \"passed\": false}, {\"check\": \"references without candidates\", \"actual\": [[\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"c\"], [\"z\"], [\"z\"], [null], [null]], \"expected\": [[\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"c\"], [\"z\"], [\"z\"], [null], [null]], \"passed\": true}, {\"check\": \"mixed nullable groups duplicates ties and truth flags\", \"actual\": [[\" a \"], [\"\"], [\"A\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"c\"], [\"d\"], [\"z\"], [\"z\"], [null], [null], [null]], \"expected\": [[\" a \"], [\"\"], [\"A\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [\"z\"], [\"z\"], [null], [null], [null], [null], [null]], \"passed\": false}, {\"check\": \"unknown-only group with duplicate nullable index keys\", \"actual\": [[\"x\"], [null], [null]], \"expected\": [[\"x\"], [null], [null], [null]], \"passed\": false}, {\"check\": \"single known zero and matching reference\", \"actual\": [[\"a\"], [\"a\"]], \"expected\": [[\"a\"], [\"a\"]], \"passed\": true}, {\"check\": \"negative-only group and missing measurement\", \"actual\": [[\"n\"], [\"n\"]], \"expected\": [[\"n\"], [\"n\"], [\"n\"], [\"n\"]], \"passed\": false}, {\"check\": \"positive-only group with repeated measurements and NULL\", \"actual\": [[\"p\"], [\"p\"], [\"p\"]], \"expected\": [[\"p\"], [\"p\"], [\"p\"], [\"p\"], [\"p\"], [\"p\"]], \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":41.633,"exit_code":0,"observations":[{"actual":[],"check":"empty relations","expected":[],"passed":true},{"actual":[[" a "],[""],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["c"],["d"],["d"],["d"],[null],[null],[null]],"check":"left facts without references","expected":[[" a "],[""],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["c"],["d"],["d"],["d"],[null],[null],[null]],"passed":true},{"actual":[["A"],["a"],["a"],["a"],["a"],["b"],["b"],["c"],["z"],["z"],[null],[null]],"check":"references without candidates","expected":[["A"],["a"],["a"],["a"],["a"],["b"],["b"],["c"],["z"],["z"],[null],[null]],"passed":true},{"actual":[[" a "],[""],["A"],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["b"],["b"],["c"],["c"],["d"],["d"],["d"],["z"],["z"],[null],[null],[null],[null],[null]],"check":"mixed nullable groups duplicates ties and truth flags","expected":[[" a "],[""],["A"],["A"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["a"],["b"],["b"],["b"],["b"],["b"],["c"],["c"],["d"],["d"],["d"],["z"],["z"],[null],[null],[null],[null],[null]],"passed":true},{"actual":[["x"],[null],[null],[null]],"check":"unknown-only group with duplicate nullable index keys","expected":[["x"],[null],[null],[null]],"passed":true},{"actual":[["a"],["a"]],"check":"single known zero and matching reference","expected":[["a"],["a"]],"passed":true},{"actual":[["n"],["n"],["n"],["n"]],"check":"negative-only group and missing measurement","expected":[["n"],["n"],["n"],["n"]],"passed":true},{"actual":[["p"],["p"],["p"],["p"],["p"],["p"]],"check":"positive-only group with repeated measurements and NULL","expected":[["p"],["p"],["p"],["p"],["p"],["p"]],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty relations\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"left facts without references\", \"actual\": [[\" a \"], [\"\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [null], [null], [null]], \"expected\": [[\" a \"], [\"\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [null], [null], [null]], \"passed\": true}, {\"check\": \"references without candidates\", \"actual\": [[\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"c\"], [\"z\"], [\"z\"], [null], [null]], \"expected\": [[\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"c\"], [\"z\"], [\"z\"], [null], [null]], \"passed\": true}, {\"check\": \"mixed nullable groups duplicates ties and truth flags\", \"actual\": [[\" a \"], [\"\"], [\"A\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [\"z\"], [\"z\"], [null], [null], [null], [null], [null]], \"expected\": [[\" a \"], [\"\"], [\"A\"], [\"A\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"a\"], [\"b\"], [\"b\"], [\"b\"], [\"b\"], [\"b\"], [\"c\"], [\"c\"], [\"d\"], [\"d\"], [\"d\"], [\"z\"], [\"z\"], [null], [null], [null], [null], [null]], \"passed\": true}, {\"check\": \"unknown-only group with duplicate nullable index keys\", \"actual\": [[\"x\"], [null], [null], [null]], \"expected\": [[\"x\"], [null], [null], [null]], \"passed\": true}, {\"check\": \"single known zero and matching reference\", \"actual\": [[\"a\"], [\"a\"]], \"expected\": [[\"a\"], [\"a\"]], \"passed\": true}, {\"check\": \"negative-only group and missing measurement\", \"actual\": [[\"n\"], [\"n\"], [\"n\"], [\"n\"]], \"expected\": [[\"n\"], [\"n\"], [\"n\"], [\"n\"]], \"passed\": true}, {\"check\": \"positive-only group with repeated measurements and NULL\", \"actual\": [[\"p\"], [\"p\"], [\"p\"], [\"p\"], [\"p\"], [\"p\"]], \"expected\": [[\"p\"], [\"p\"], [\"p\"], [\"p\"], [\"p\"], [\"p\"]], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}