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This article will explain in detail which fields are suitable for indexing in mysql. The editor thinks it is very practical, so I share it with you as a reference. I hope you can get something after reading this article.

The fields in the database that are suitable for adding indexes include fields in a table with a higher degree of dispersion, fields that occupy less storage space, fields with fixed storage space, fields that are often used in the where clause, and so on.

1. The higher the discreteness of a field in a table, the more suitable it is to be selected as an index keyword. Primary key fields and uniqueness constraint fields are suitable for keywords selected as indexes because the values of these fields are very discrete. MySQL is thoughtful when dealing with primary key constraints and uniqueness constraints. When a database user creates a primary key constraint, MySQL automatically creates a primary index (primary index), and the index name is called Primary;. When a database user creates a unique index, MySQL automatically creates a unique index (unique index). By default, the index name is the field name of the unique index.

2. Fields that take up less storage space are more suitable for keywords to be selected as indexes. For example, an integer field takes up less storage space than a string, so it is more suitable to be selected as an index keyword.

3. Fields with fixed storage space are more suitable for keywords selected as indexes. Compared with fields of type text, fields of type char are more suitable to be selected as index keywords.

4. The fields that are often used in the Where clause should be indexed, grouped or sorted fields should be indexed, and the join fields of the two tables should be indexed.

5. Fields that are updated frequently are not suitable for creating indexes, and fields that do not appear in the where clause should not be indexed.

About which fields are suitable for indexing in mysql to share here, I hope the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.

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