Documentation Home
MySQL 8.4 Reference Manual
Related Documentation Download this Manual
PDF (US Ltr) - 39.8Mb
PDF (A4) - 39.9Mb
Man Pages (TGZ) - 257.9Kb
Man Pages (Zip) - 364.9Kb
Info (Gzip) - 4.0Mb
Info (Zip) - 4.0Mb


MySQL 8.4 Reference Manual  /  ...  /  Using COLLATE in SQL Statements

12.8.1 在 SQL 语句中使用 COLLATE

使用 COLLATE 子句,可以覆盖比较操作的默认排序规则。COLLATE 可以在 SQL 语句中的多个部分使用。以下是一些示例:

  • 使用 ORDER BY :

    SELECT k
    FROM t1
    ORDER BY k COLLATE latin1_german2_ci;
  • 使用 AS :

    SELECT k COLLATE latin1_german2_ci AS k1
    FROM t1
    ORDER BY k1;
  • 使用 GROUP BY :

    SELECT k
    FROM t1
    GROUP BY k COLLATE latin1_german2_ci;
  • 使用聚合函数:

    SELECT MAX(k COLLATE latin1_german2_ci)
    FROM t1;
  • 使用 DISTINCT :

    SELECT DISTINCT k COLLATE latin1_german2_ci
    FROM t1;
  • 使用 WHERE :

    SELECT *
    FROM t1
    WHERE _latin1 'Müller' COLLATE latin1_german2_ci = k;
    SELECT *
    FROM t1
    WHERE k LIKE _latin1 'Müller' COLLATE latin1_german2_ci;
  • 使用 HAVING :

    SELECT k
    FROM t1
    GROUP BY k
    HAVING k = _latin1 'Müller' COLLATE latin1_german2_ci;