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sql php mysql

表名: table1 
字段: id value(数字加逗号/多少个数字不确定)
内容A: 1   3,5
内容B: 2   3,3
内容C: 3   3,4,5
内容D: 4   5,3,6
我要实现的就是 查找 对应id 将value字段中的3 替换为4 只替换一个

最终要实现的效果
内容A: 1   4,5
内容B: 2   4,3
内容C: 3   4,4,5
内容D: 4   5,4,6

sql语句:

回复讨论(解决方案)

oracle的,mysql没有测试,把对应的函数换成mysql的应该就可以了。
select replace(firstStr, 's', 'a')||secondStr
  from (SELECT substr(str, 0, instr(str, 's')) firstStr,
               substr(str, instr(str, 's')+1) secondStr
          FROM (select t1.value str  from table1 t1 where t1.id=1))

不好意思刚刚那个忘记换个字符。
oracle的,mysql没有测试,把对应的函数换成mysql的应该就可以了。
select replace(firstStr, '4', '3')||secondStr
  from (SELECT substr(str, 0, instr(str, '4')) firstStr,
               substr(str, instr(str, '4')+1) secondStr
          FROM (select t1.value str  from table1 t1 where t1.id=1))

select replace(firstStr, '3', '4')||secondStr
  from (SELECT substr(str, 0, instr(str, '3')) firstStr,
               substr(str, instr(str, '3')+1) secondStr
          FROM (select t1.value str  from table1 t1 where t1.id=1))

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