复制MySQL> select substring(abcd,据库0,2); +-----------------------+ | substring(abcd,0,2) | +-----------------------+ | | +-----------------------+ 1 row in set (0.00 sec) MySQL> select substring(abcd,1,2); +-----------------------+ | substring(abcd,1,2) | +-----------------------+ | ab | +-----------------------+ 1 row in set (0.02 sec) TRIM([[BOTH|LEADING|TRAILING] [padding] FROM]string2) 1.2.3.4.5.6.7.8.9.10.11.12.13.14.15. |
喜欢
讨厌