10.8.1 在 SQL 语句中使用 COLLATE
使用COLLATE
子句,您可以覆盖默认的默认排序规则以进行比较。 COLLATE
可用于 SQL 语句的各个部分。这里有些例子:
- 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;
- 具有聚合功能:
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;