Bug #119698 rows become less unexpectedly caused by on clause
Submitted: 16 Jan 7:08 Modified: 16 Jan 9:16
Reporter: Aaditya Dubey Email Updates:
Status: Verified Impact on me:
None 
Category:MySQL Server: Optimizer Severity:S3 (Non-critical)
Version:8.0. OS:Any
Assigned to: CPU Architecture:Any

[16 Jan 7:08] Aaditya Dubey
Description:
after changing on clause to forever TRUE,rows become less unexpectedly

mysql> WITH cte_219 AS (SELECT SIN(qmr4.c7) AS col_1, 1 AS col_2, qmr4.c2 AS col_3 FROM t3 AS qmr4 USE INDEX (idx_t3_c11_c5_c7)) (SELECT 1 AS col_1, ftb26.col_3 AS col_2, neu25.c1 AS col_3, COS(neu25.c1) AS col_4 FROM t1 AS neu25 USE INDEX (idx_t1_c2) INNER JOIN cte_219 AS ftb26 ON EXISTS(SELECT rel45.col_1 AS col_1 FROM cte_219 AS rel45 WHERE (neu25.c1 = rel45.col_1) ORDER BY rel45.col_1 LIMIT 1));
+-------+-------+-------+---------------------+
| col_1 | col_2 | col_3 | col_4               |
+-------+-------+-------+---------------------+
|     1 |  9828 |   954 |  0.5026225011234452 |
|     1 |  4362 |   954 |  0.5026225011234452 |
...
96 rows in set (0.00 sec)
mysql> WITH cte_219 AS (SELECT SIN(qmr4.c7) AS col_1, 1 AS col_2, qmr4.c2 AS col_3 FROM t3 AS qmr4 USE INDEX (idx_t3_c11_c5_c7)) (SELECT 1 AS col_1, ftb26.col_3 AS col_2, neu25.c1 AS col_3, COS(neu25.c1) AS col_4 FROM t1 AS neu25 USE INDEX (idx_t1_c2) INNER JOIN cte_219 AS ftb26 ON ('1' = '1'));
+-------+-------+-------+---------------------+
| col_1 | col_2 | col_3 | col_4               |
+-------+-------+-------+---------------------+
|     1 |  9828 |   954 |  0.5026225011234452 |
....
24 rows in set (0.00 sec)

How to repeat:
DROP DATABASE IF EXISTS test;
CREATE DATABASE IF NOT EXISTS test;
USE test;
CREATE TABLE t1 (
    c1 INT NOT NULL AUTO_INCREMENT,
    c2 VARCHAR(255) NOT NULL,
    c3 VARCHAR(255) NULL,
    c4 INT NULL,
    c5 DATE NOT NULL,
    c6 VARCHAR(10) NOT NULL,
    PRIMARY KEY (c1)
);
CREATE TABLE t3 (
    c1 INT NOT NULL AUTO_INCREMENT,
    c2 INT NOT NULL,
    c3 INT NOT NULL,
    c4 YEAR NOT NULL,
    c5 TIME NULL,
    c6 TINYINT NULL,
    c7 SMALLINT NULL,
    c8 MEDIUMINT NULL,
    c9 BIGINT NULL,
    c10 LONGTEXT NULL,
    c11 VARCHAR(255) NULL,
    c12 TINYTEXT NULL,
    c13 TINYBLOB NULL,
    c14 SET('x','y','z') NULL,
    c15 TINYINT(1) NULL,
    PRIMARY KEY (c1)
);
INSERT INTO t1 (c1, c2, c3, c4, c5, c6) VALUES (3584, 'sample_AQJP3FCb7PX46hF2d3VoKsPIHtIgzieVgOK1Ue7iSbNProjjh', 'sample_v', 36, '2025-09-07', 'sample_J');
INSERT INTO t1 (c1, c2, c3, c4, c5, c6) VALUES (954, 'sample_0kfPnPKeUjkycwqHxj5OtQ8', 'sample_sQ', 90, '2025-10-10', 'sample_C');
INSERT INTO t1 (c1, c2, c3, c4, c5, c6) VALUES (1986, 'sample_tJaorTY4zIEBbb8IM4auYieeVSd80foFpJh3MIv0Rz8fEgfYthMyHLdUMnlIN6NnP0VoAFBpSEUcHovYpCFbGrC98Y52vXpgXsmsEBDYj6ecgN2JkDh393f4hhIjFLpqffJrE5Z09WtyvK6PT0IcDNjF6S16yhunjPWFxaAbK4Z6', 'sample_bIa5736UIVD92z8u5rQ0PaRpPlOEwroZ4Xoqc4jDp4SiRROqU4u2EvOZZupAHmFPuFcWjOC6V16yTz58i3824l1EdwAgMPAPy9RM2sHerAB3L3eAWFGFd', 68, '2025-04-20', 'sample_KWK');
INSERT INTO t1 (c1, c2, c3, c4, c5, c6) VALUES (6432, 'sample_apUxsuYxJ7yJ6etwr3Sd7Cg7l1JHXVRSgSUF689u4w2greqF3zbivycDbv6qA4Wusopmd80qoDFLGg1ercUJBRyEl0j0aw1JXgj35Pg4JK2lNYBG2UPKBvS3jhsYpkYbhUNtq5zfTal0MXOuOk4CydQWObucwCG1tGcBtxVHzwZf18W2M7Fl2c8AzYVIIn', 'sample_xoju7XvqD9RJhJ2NAoI2KxR5QZdZKDIjrOdN8MahX1k3dJu9UxKIjMzLtBjiMnoN5JxDvSR7bHNsAECcv5onlaOPg4TBQg4yQw6ThZm8lvYZcq9lBqZap4SoxgEZLdQaIflJvl7EcmCUqqRgQEes', 48, '2025-04-28', 'sample_N');
INSERT INTO t1 (c1, c2, c3, c4, c5, c6) VALUES (8644, 'sample_IYRIsvectgAbcVIlfnvNd9kX3FNkOo4kAKKY1BDBLFQpH7ksvMtBllsZK16dP8T7twvH59dyaLTQuKIciaq8hnHB49XU7pS4kDw8Gt9mASD1ylSfvFBVtDNT', 'sample_7K12anyKLHlFNF5tfck9rj0CREpw10By71a2xm7uMRqIH61pLHnO3mXiWV0Ql013c5vK', 37, '2024-11-16', 'sample_8');
INSERT INTO t1 (c1, c2, c3, c4, c5, c6) VALUES (9828, 'sample_mbTbyuGtnVI5eoQZozrqRGnCbFGq5YiJjIAQ6m5pyEN0KYZtC8nHtcPrUXpN8Ox9SpGW03NGGx1rgIfMQzTzUQDSJyNReXc7SzF8lxZGBkTzeRFfSuV1', 'sample_w848NDNkIDLOlkpaaODWH9A0RwNZ3y4Up1tGogrgGXva1pea9fQC785AX81aC0JjCpCfVuAhR3sedKdIDkph0vCxL9t6vWoUxCcx1Z1PhcFsDkuO86Lm30jCHqsgwEkByFdBtl9Dapi0UdGLs4O7Nt1LJOAjxDeWrmGT52FyIlsB1dVyP84albq7J7x5ZLVhHk0pCHeRKK4Tq', 6, '2024-12-11', 'sample_Yb');
INSERT INTO t3 (c1, c2, c3, c4, c5, c6, c7, c8, c9, c10, c11, c12, c13, c14, c15) VALUES (8417, 9828, 4869, 2023, '2023-01-01 21:39:34', 14, 68, 41, 89, 'sample_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', 'sample_weZoLCxaYRuEbIZSAcw', 'sample_8eD325FzN79CIA1lx3hcxnIVFhKIlbppGhso8TzRvfqzVgovF4texBWt2e15D4TE8uXMELQHhSBEC2wHYIIOfKH8XCNMYbzkX06yuiY1u41mec1TesgBYKV3PW', X'D2A6D881052BECAA90E6BDA5DBAF542830D084', 'y,z', NULL);
INSERT INTO t3 (c1, c2, c3, c4, c5, c6, c7, c8, c9, c10, c11, c12, c13, c14, c15) VALUES (4582, 4362, 2120, 2003, '2023-01-01 10:35:52', 75, 23, 4, 15, 'sample_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', 'sample_OMHD5WHEEeP825gAmH18ASwpqD0vYvORsqY1JeLMWv1WSXtxcKBge9eMlrt8UeUiKPtnRDLe7zuoeaiI0BBpG6bPMb4748Gm2MMEjEMRdiEm5VkF5QaLxVYgs6sG6EnjckihkivneYHGmNCgBVP9h0idYcjBp08sH7kN7o8xZS6XyAI2A8sln4cm', 'sample_jOWhHNwQUt1uJx2kPyP1w12xx0VmItQqrpMFoAK5Q5hzAwk6IdTs6Zs4O0fk3TBmFAOgiAO9uWZqt4c', X'4FEFAA9A7DEFA08134185EE2B8A908', 'y,x', NULL);
INSERT INTO t3 (c1, c2, c3, c4, c5, c6, c7, c8, c9, c10, c11, c12, c13, c14, c15) VALUES (5671, 6432, 994, 2007, '2023-01-01 03:06:53', 9, 46, 38, 20, 'sample_IgunjWtOnhzMxUH9Ad6ztAz1RATtk0dLGWZI04tEFxDc3YGNltqWLpjA1Zdiy0PzXAPr446Tqj0z4WKHyW7vRqz4XwCvGBYI2jaMMRvhftO4q2uNb8GqE4pITSPpgZnqO6QNHAMfDUSy413xdlhdBXRHUiFNmfld6A6pRgpBbo69hf6MpqhA4uKL4fT7lunYOzXI7ftuq3I8izzucoUA1LLfeMezTjFSYGQ5YWSq4wYPS4xh5ip5FdYmEHV1U6S3EBtFEjzgWSVcU', 'sample_2xSG6kX0B2smVHvvQD77wD26NFKaoY3vFA1Ty5whGT50gMyzP69v8mQNea4TTSnfikdbSOjlgnF3mpiXkmNPVHfDG5TP6E8Z3spsOedSyucPJ7iS91t4SXWQh5nEl70ciocI1tqu', 'sample_V9eyQD3ic2DoRT53i76gSpkmcH7Ge0SLXYqppVH1yO6thE1RMpOZxm6R', X'E9AF89E69587', 'z', NULL);
INSERT INTO t3 (c1, c2, c3, c4, c5, c6, c7, c8, c9, c10, c11, c12, c13, c14, c15) VALUES (1609, 9828, 2120, 2002, '2023-01-01 16:32:23', 38, 39, 92, 58, 'sample_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', 'sample_BG5pG2qcXsHF4L2NnVrMX6VTic5BkzqnbWb56WsXYkJZnDQiX183nLVfMWUowf5wXKKCVpvdOb0cnmozbVE8rTNsCWOaNUs7IIUqI79ChL14Dh9UjofKJF0BYN8NnMd7VmeVUt98C8dvr20RY33brrBsRaUxUdg0Gs6JhAKl1PxZcRyTxSlSWn1SEiKU', 'sample_bVEDTl6xDaU5w7nREFRKU', X'CDBADAB6EFACA50AEF8896D6A2', 'y', NULL);
CREATE  INDEX idx_t1_c2 ON t1 (c2(63));
CREATE  INDEX idx_t3_c11_c5_c7 ON t3 (c11(63), c5, c7);
WITH cte_219 AS (SELECT SIN(qmr4.c7) AS col_1, 1 AS col_2, qmr4.c2 AS col_3 FROM t3 AS qmr4 USE INDEX (idx_t3_c11_c5_c7)) (SELECT 1 AS col_1, ftb26.col_3 AS col_2, neu25.c1 AS col_3, COS(neu25.c1) AS col_4 FROM t1 AS neu25 USE INDEX (idx_t1_c2) INNER JOIN cte_219 AS ftb26 ON EXISTS(SELECT rel45.col_1 AS col_1 FROM cte_219 AS rel45 WHERE (neu25.c1 = rel45.col_1) ORDER BY rel45.col_1 LIMIT 1));
WITH cte_219 AS (SELECT SIN(qmr4.c7) AS col_1, 1 AS col_2, qmr4.c2 AS col_3 FROM t3 AS qmr4 USE INDEX (idx_t3_c11_c5_c7)) (SELECT 1 AS col_1, ftb26.col_3 AS col_2, neu25.c1 AS col_3, COS(neu25.c1) AS col_4 FROM t1 AS neu25 USE INDEX (idx_t1_c2) INNER JOIN cte_219 AS ftb26 ON ('1' = '1'));
[16 Jan 9:16] Roy Lyseng
Thank you for the bug report.
Verified as described.