SQL的locate和substr函數

原創 柚子哦 2020-06-04 06:47

locate函數：

  • locate(substr,str) 　 substr在字符串str中第一次出現的位置
  • locate(substr,str,pos)     從位置pos開始，substr在字符串str中第一次出現的位置。若substr不在str中，則返回0。

 

substr函數：

  • substr(str,pos,len)     從位置pos開始，截取len個字符
  • substr(str,pos)     從位置pos開始，一直截取到最後
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