STRPOS
返回一个 INTEGER 值，该值表示指定子字符串在字符串中的位置（从 1 开始计数）。如果未找到子字符串，则 STRPOS 返回 0。
STRPOS 类似于 POSITION；但 POSITION 允许按字符和八位字节查找。
行为类型
不可变语法
STRPOS ( string‑expression , substring )
参数
- string-expression
- 要在其中定位 子字符串的字符串
- substring
- 要在 string-expression 中定位的子字符串
示例
=> SELECT ship_type, shipping_key, strpos (ship_type, 'DAY') FROM shipping_dimension WHERE strpos > 0 ORDER BY ship_type, shipping_key;
ship_type | shipping_key | strpos
--------------------------------+--------------+--------
NEXT DAY | 1 | 6
NEXT DAY | 13 | 6
NEXT DAY | 19 | 6
NEXT DAY | 22 | 6
NEXT DAY | 26 | 6
NEXT DAY | 30 | 6
NEXT DAY | 34 | 6
NEXT DAY | 38 | 6
NEXT DAY | 45 | 6
NEXT DAY | 51 | 6
NEXT DAY | 67 | 6
NEXT DAY | 69 | 6
NEXT DAY | 80 | 6
NEXT DAY | 90 | 6
NEXT DAY | 96 | 6
NEXT DAY | 98 | 6
TWO DAY | 9 | 5
TWO DAY | 21 | 5
TWO DAY | 28 | 5
TWO DAY | 32 | 5
TWO DAY | 40 | 5
TWO DAY | 43 | 5
TWO DAY | 49 | 5
TWO DAY | 50 | 5
TWO DAY | 52 | 5
TWO DAY | 53 | 5
TWO DAY | 61 | 5
TWO DAY | 73 | 5
TWO DAY | 81 | 5
TWO DAY | 83 | 5
TWO DAY | 84 | 5
TWO DAY | 85 | 5
TWO DAY | 94 | 5
TWO DAY | 100 | 5
(34 rows)