![](https://img.laitimes.com/img/9ZDMuAjOiMmIsIjOiQnIsIiY4ETZhJzNx0TZjJXdvN3PnBnaucHM0QTMfFTZ4UDOjBDZ3UWZ3QGM5Q2M4cDMlVWM3EGMxYGOmF2YtIjdvwVbvNmLn1WaopnLxMWaw9CXvwlOzBHd0hWPsJXdmYDM3YjZkJGNzQDNl1SOhRGOtETMiVWLlJDNm1SOihTNiFWMh1DZpV3ZmITPlBXe0ZyPldWYtl2LcdXZpZ3Lc12bj5SZjVjL5h3byBnLyATLn1Wavw1LcpDc0RHaiojIsJye.jpg)
作者: 藍精靈lx
https://blog.csdn.net/liuxiao723846/article/details/50341821
1、locate函數可以實作類似indexof的功能,locate(substr,str)傳回substr子串在字元串str中的位置。
2、substring函數,截取字元串:
substring(str, pos)
substring(str, pos, length)
說明:substring(被截取字段,從第幾位開始截取)
substring(被截取字段,從第幾位開始截取,截取長度)
3、按關鍵字截取字元串 :
substring_index(str,delim,count)
說明:substring_index(被截取字段,關鍵字,關鍵字出現的次數)
例:select substring_index("http://blog.jb51.net",".",2) as abstract from my_content_t
結果:blog.jb51