问题描述
我需要插入，但前提是不存在类似记录
例如:
I need to make a insert but only if similar record don't exists
for example:
INSERT INTO requests ('user_id','subject','text','time') VALUES (56,'test','test 1234',6516516)
INSERT INTO requests ('user_id','subject','text','time') VALUES (56,'test','test 1234',6516516)
但要检查另一条记录中是否有相同的主题"和文本":
but to check if there are same 'subject' and 'text' in another record to:
- 不插入任何东西
- 更新时间"和用户 ID"
这两种情况我都需要 sql，因为我现在不确定要使用什么.
提前致谢！
I need sql for both cases because I'm no sure at this moment what I'm going to use.
Thanks in advance!
推荐答案
INSERT INTO requests ('user_id','subject','text','time')
VALUES (56,'test','test 1234',6516516)
ON DUPLICATE KEY UPDATE time = VALUES(time), user_id = VALUES(user_id)
将相关列设置为索引 UNIQUE.
Have the relevant columns set to index UNIQUE.
这将插入一行，但如果主题或文本(或两者)已存在，则改为使用给定的 time 和 user_id
This will insert a row, but if subject or text (or both) already exist, you instead update the existing row with given time and user_id
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