如果存在则更新 MySQL [英] IF Exists Then Update MySQL

问题描述

我试图更新一行，如果它存在，如果它不存在，那么我想在表中执行插入操作.图片.id &picture.picturepath 是一个唯一的键.我看过一些例子，但我不确定我做错了什么.

I am trying to update a row if its exists, if it does not exist then I want to perform an insert into the table. The picture.id & picture.picturepath are a unique key. I have looked at some examples but I am not sure What I am doing wrong.

我遇到了重复的密钥更新，不确定这是否与我要实现的目标有关.

I have come across on duplicate key update, not sure if this is relevant to what I am trying to achieve.

Error message: 1064- You have an error in your SQL syntax near 'UPDATE picture SET picture.picturecontent = ipicturecontent WHERE picture.id at line 5"


    IF EXISTS( SELECT * FROM picture WHERE picture.id = ipictureid 
    AND picture.picturepath = ipicturepath) THEN

    UPDATE picture 
    SET picture.picturecontent = ipicturecontent
    WHERE picture.id = ipictureid 
    AND picture.picturepath = ipicturepath

    ELSE

    INSERT INTO picture (picture.id, picture.picturecontent,picture.picturepath) VALUES (ipictureid, ipicturecontent, ipicturepath)

推荐答案

https://stackoverflow.com/a/10095812/1287480 <- 信用到期的信用

https://stackoverflow.com/a/10095812/1287480 <- Credit where credit is due

插入模型(col1、col2、col3)值 ('foo', 'bar', 'alpha')重复密钥更新 col3='alpha';

INSERT INTO models (col1, col2, col3) VALUES ('foo', 'bar', 'alpha') ON DUPLICATE KEY UPDATE col3='alpha';

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