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  1. MariaDB Server
  2. MDEV-30034

UNIQUE USING HASH accepts duplicate entries for tricky collations

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    Description

      If I use a traditional unique constraint, the table correctly rejects the second record:

      CREATE OR REPLACE TABLE t1 (a VARCHAR(2000) COLLATE utf8_unicode_nopad_ci, UNIQUE(a(3)));
      		 
      INSERT INTO t1 VALUES ('ss ');
      		 
      INSERT INTO t1 VALUES ('ß ');


      ERROR 1062 (23000): Duplicate entry 'ß ' for key 'a'

      Now if I do the same thing with UNIQUE USING HASH, it accepts the duplicate record:

      CREATE OR REPLACE TABLE t1 (a VARCHAR(2000) COLLATE utf8_unicode_nopad_ci, UNIQUE(a(3)) USING HASH);
      		 
      INSERT INTO t1 VALUES ('ss ');
      		 
      INSERT INTO t1 VALUES ('ß ');

      This is wrong. The second record should be rejected.

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          is caused by

          Task - A task that needs to be done. MDEV-371 Unique indexes for blobs

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

          Bug - A problem which impairs or prevents the functions of the product. MDEV-25904 New collation functions to compare InnoDB style trimmed NO PAD strings

          • Major - Major loss of function.
          • Closed
          relates to

          Bug - A problem which impairs or prevents the functions of the product. MDEV-30048 Prefix keys for CHAR work differently for MyISAM vs InnoDB

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

          Bug - A problem which impairs or prevents the functions of the product. MDEV-30050 Inconsistent results of DISTINCT with NOPAD

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

          Bug - A problem which impairs or prevents the functions of the product. MDEV-30072 Wrong ORDER BY for a partitioned prefix key + NOPAD

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

          Bug - A problem which impairs or prevents the functions of the product. MDEV-27670 Assertion `(cs->state & 0x20000) == 0' failed in my_strnncollsp_nchars_generic_8bit

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

          Bug - A problem which impairs or prevents the functions of the product. MDEV-27768 MDEV-25440: Assertion `(cs->state & 0x20000) == 0' failed in my_strnncollsp_nchars_generic_8bit

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

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              bar Alexander Barkov
              bar Alexander Barkov
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                Updated:
                Resolved:

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