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  1. MariaDB Server
  2. MDEV-8723

Wrong result for SELECT..WHERE COLLATION(a)='binary' AND a='a'

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      Description

      In this script:

      DROP TABLE IF EXISTS t1;
      		 
      CREATE TABLE t1 (a VARBINARY(10));
      		 
      INSERT INTO t1 VALUES ('a');
      		 
      SELECT * FROM t1 WHERE COLLATION(a)='binary';
      		 
      SELECT * FROM t1 WHERE a='a';

      the two SELECT queries return one row.

      Now if I join both conditions using AND in the same query:

      SELECT * FROM t1 WHERE COLLATION(a)='binary' AND a='a';

      It returns empty set.

      A similar script:

      DROP TABLE IF EXISTS t1;
      		 
      CREATE TABLE t1 (a VARBINARY(10));
      		 
      INSERT INTO t1 VALUES ('a');
      		 
      SELECT * FROM t1 WHERE CHARSET(a)='binary';
      		 
      SELECT * FROM t1 WHERE a='a'; 
      SELECT * FROM t1 WHERE CHARSET(a)='binary' AND a='a';

      A similar script:

      DROP TABLE IF EXISTS t1;
      		 
      CREATE TABLE t1 (a VARBINARY(10));
      		 
      INSERT INTO t1 VALUES ('a');
      		 
      SELECT * FROM t1 WHERE COERCIBILITY(a)=2;
      		 
      SELECT * FROM t1 WHERE a='a'; 
      SELECT * FROM t1 WHERE COERCIBILITY(a)=2 AND a='a';

      A similar script:

      DROP TABLE IF EXISTS t1;
      		 
      CREATE TABLE t1 (a VARBINARY(10));
      		 
      INSERT INTO t1 VALUES ('a');
      		 
      SELECT * FROM t1 WHERE WEIGHT_STRING(a)='a';
      		 
      SELECT * FROM t1 WHERE a='a'; 
      SELECT * FROM t1 WHERE WEIGHT_STRING(a)='a' AND a='a';

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          blocks

          Bug - A problem which impairs or prevents the functions of the product. MDEV-8728 Fix a number of problems in equal field and equal expression propagation

          • Critical - Crashes, loss of data, severe memory leak.
          • Closed
          relates to

          Bug - A problem which impairs or prevents the functions of the product. MDEV-8695 Wrong result for SELECT..WHERE varchar_column='a' AND CRC32(varchar_column)=3904355907

          • Major - Major loss of function.
          • Closed

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              Assignee:
              bar Alexander Barkov
              Reporter:
              bar Alexander Barkov
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                Dates

                Created:
                Updated:
                Resolved:

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