如何使用 sql server 执行 BEFORE UPDATED 触发器?
我正在使用 Sqlserver express，但我无法在更新之前执行 触发器.还有其他方法吗?
I'm using Sqlserver express and I can't do before updated trigger. There's a other way to do that?
推荐答案
MSSQL 不支持 BEFORE 触发器.最接近的是 INSTEAD OF 触发器，但它们的行为与 MySQL 中的 BEFORE 触发器不同.
MSSQL does not support BEFORE triggers. The closest you have is INSTEAD OF triggers but their behavior is different to that of BEFORE triggers in MySQL.
您可以在此处了解有关它们的更多信息，并注意 INSTEAD OF 触发器指定执行触发器而不是触发 SQL 语句，从而覆盖触发语句的操作."因此，如果触发器未正确写入/处理，则可能不会发生对更新的操作.级联操作也会受到影响.
You can learn more about them here, and note that INSTEAD OF triggers "Specifies that the trigger is executed instead of the triggering SQL statement, thus overriding the actions of the triggering statements." Thus, actions on the update may not take place if the trigger is not properly written/handled. Cascading actions are also affected.
您可能想要使用不同的方法来实现您的目标.
You may instead want to use a different approach to what you are trying to achieve.
相关文章