concat

description

Syntax

VARCHAR concat(VARCHAR,...)

将多个字符串连接起来, 如果参数中任意一个值是 NULL,那么返回的结果就是 NULL

example

  1. mysql> select concat("a", "b");
  2. +------------------+
  3. | concat('a', 'b') |
  4. +------------------+
  5. | ab |
  6. +------------------+
  7. mysql> select concat("a", "b", "c");
  8. +-----------------------+
  9. | concat('a', 'b', 'c') |
  10. +-----------------------+
  11. | abc |
  12. +-----------------------+
  13. mysql> select concat("a", null, "c");
  14. +------------------------+
  15. | concat('a', NULL, 'c') |
  16. +------------------------+
  17. | NULL |
  18. +------------------------+

keywords

  1. CONCAT