select cast ('12345' as integer); * 用substring截取字符串,从第8个字符开始截取2个字符 select cast (substring('123344654',8,2) as integer);

替换字符串方法及字符串操作函数

  • 替换字符串实例
  • * 把字段coulmn_name里的字符"aaa"替换为'0'
    update table_name set coulmn_name=replace(a,"aaa","0");