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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