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  1. MariaDB Server
  2. MDEV-8167

XOR returns bad results for an indexed column

        Details

        • Type: Bug
        • Status: Closed
        • Priority: Major
        • Resolution: Fixed
        • Affects Version/s: 10.1, 10.0, 5.5
        • Fix Version/s: 10.1.6
        • Component/s: Optimizer
        • Labels:
          None

          Description

          This script:

          DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (
  id INTEGER UNSIGNED NOT NULL AUTO_INCREMENT,
   k INTEGER UNSIGNED DEFAULT '0' NOT NULL,
   c CHAR(120) DEFAULT '' NOT NULL,
   pad CHAR(60) DEFAULT '' NOT NULL,
   PRIMARY KEY (id)
) ENGINE=MyISAM;
INSERT INTO t1 (k, c, pad) VALUES (10, 'a', 'xxx');
INSERT INTO t1 (k, c, pad) VALUES (11, 'a', 'xxx');
INSERT INTO t1 (k, c, pad) VALUES (12, 'a', 'xxx');
INSERT INTO t1 (k, c, pad) VALUES (13, 'a', 'xxx');
INSERT INTO t1 (k, c, pad) VALUES (14, 'a', 'xxx');
INSERT INTO t1 (k, c, pad) VALUES (15, 'a', 'xxx');
INSERT INTO t1 (k, c, pad) VALUES (16, 'a', 'xxx');
SELECT * FROM t1 WHERE id XOR 0;

          erroneously returns empty set.

          If I add IGNORE KEY:

          SELECT * FROM t1 IGNORE KEY(PRIMARY) WHERE id XOR 0;

          it correctly returns rows:

          +----+----+---+-----+
| id | k  | c | pad |
+----+----+---+-----+
|  1 | 10 | a | xxx |
|  2 | 11 | a | xxx |
|  3 | 12 | a | xxx |
|  4 | 13 | a | xxx |
|  5 | 14 | a | xxx |
|  6 | 15 | a | xxx |
|  7 | 16 | a | xxx |
+----+----+---+-----+
7 rows in set (0.00 sec)

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                  • Assignee:
                    bar Alexander Barkov
                    Reporter:
                    bar Alexander Barkov
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                    Dates

                    • Created:
                      Updated:
                      Resolved: