标签：span 获取 ast sql -- style div break code
MID(s,n,len) 用于获取指定位置的子字符串
mysql> SELECT MID(‘breakfast‘,5) AS col1, # 从第5个字符串开始获取 -> MID(‘breakfast‘,5,3) AS col2, # 从第5个字符串开始，获取3个 -> MID(‘breakfast‘,-5) AS col3, # (倒向)从第5个字符串开始获取 -> MID(‘breakfast‘,-5,3) AS col4; # (倒向)从第5个字符串开始获取，获取3个 +-------+------+-------+------+ | col1 | col2 | col3 | col4 | +-------+------+-------+------+ | kfast | kfa | kfast | kfa | +-------+------+-------+------+
标签：span 获取 ast sql -- style div break code
原文地址：http://www.cnblogs.com/pzk7788/p/6895776.html
