What is the role of views in MySQL? Can views be changed?

This article mainly introduces you to the detailed explanation of the role of views in MySQL and whether they can be changed.

A view is a virtual table. Unlike a table containing data, a view only contains queries that dynamically retrieve data when used; it does not contain any columns or data. Using views can simplify complex SQL operations, hide specific details, and protect data; once views are created, they can be utilized in the same way as tables.
Views cannot be indexed, nor can they have associated triggers or default values. If there is order by in the view itself, order by again on the view will be overwritten.

创建视图：create view XXX as XXXXXXXXXXXXXX;

For some views, such as Distinct Union that does not use the join subquery grouping aggregation function, etc., it can be updated. Updates to the view will update the base table; but the view is mainly used for Simplifies retrieval, protects data, and is not used for updates, and most views cannot be updated.

For more MySQL view-related content, you can refer to the MySQL video tutorial or MySQL manual on the PHP Chinese website!

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