更新记录（如果存在）；否则插入
我想更新表中可能存在或不存在的记录。如果数据库中不存在，则会将其插入。
为了防止选择，我首先使用 UPDATE 语句并检查 affected_rows > 0 如果没有，那么我将此记录插入表中。
我想知道是否有更好的方法来做到这一点？
I want to update a record which may or may not be present in a table. If it is not present in the database then it will be inserted.
To prevent from select I am using UPDATE statement first and checking affected_rows > 0 if not then I am inserting this record into the table.
I was wondering if there is a better way to do this?
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
您可以使用 INSERT ... ON DUPLICATE KEY UPDATE 语法：
http://dev.mysql.com/doc/refman/4.1/en/insert-on-duplicate.html
这个和
REPLACE的区别( Femaref 的答案）是，如果键重复，REPLACE将删除旧行，然后插入新行，而这将更新现有行。You could use
INSERT ... ON DUPLICATE KEY UPDATEsyntax:http://dev.mysql.com/doc/refman/4.1/en/insert-on-duplicate.html
The difference between this and
REPLACE(Femaref's answer) is thatREPLACEwill delete the old row and then insert a new row if a key is duplicated, while this will update the existing row.