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多种津贴,最有效率吗?
原标题:SQL Multiple-Dependency UPDATE ON, what s most efficient?

我试图制造一个更新桌子的触发点,这里还有一些代人法:

IF db.table1.column5 = 1
  {UPDATE db.table5.column5 = 1;}
ELSE IF 
db.table2.column5 = 1
  {UPDATE db.table5.column5 = 1;}
ELSE IF
db.table3.column5 = 1
  {UPDATE db.table5.column5 = 1;}
ELSE IF 
db.table4.column5 = 1
  {UPDATE db.table5.column5 = 1;}

这样做的最有效方式是什么? 例如,我是否应该像上文所述那样,仅仅做一个触发点,还是应该使用OR的关键词或ELSEIF? 难道有人能向我表明如何制定守则? 这是我第一次这样做。

感谢阅读。

最佳回答

如果我理解你的要求,则在<代码>栏5上的任何时间。 表1按表4更新,你也希望更新表5的相应增长?

你们将为此使用多个触发点,一个在表1至表4中。

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