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如何创建始终在 MySQL 中具有默认值的自动生成列？

[英]How can I create an auto generated column that always has its default value in MySQL?

原文 2020-07-13 03:01:49 4 1 mysql/ sql

I want to create a MySQL column that always uses its default value and won't allow the user to insert values in it.我想创建一个始终使用其默认值并且不允许用户在其中插入值的 MySQL 列。

It's a creation_date column and I've set its default value to now(), but the user can insert any date value in this column if he wants to.这是一个 creation_date 列，我已将其默认值设置为 now()，但用户可以根据需要在此列中插入任何日期值。 The now() is only used if the user don't provide any values for that column. now() 仅在用户未为该列提供任何值时使用。

I can imagine a few ways to accomplish my goal using triggers, but, is this the right way?我可以想象几种使用触发器实现目标的方法，但是，这是正确的方法吗？

Isn't there a "protected" flag to set on the column or something like that?是否没有在列上设置“受保护”标志或类似的东西？

1 个解决方案

There is no "protected" column concept, no.没有“受保护”列的概念，没有。 You would need to use triggers.您将需要使用触发器。

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