How to view and delete a unique index in mysql

How to view and delete a unique index in mysql

How to view and delete a unique index in mysql.

View unique indexes:

Show index from mytable; // mytable is the table name.

The query result is as follows:

After a unique index is queried, run the following command to delete the unique index:

Alter table mytable drop index mdl_tag_use_ix; // mdl_tag_use_ix is the index name found in the preceding table, key_name

How to view MySQL Indexes

If yes, it is 1. · Key_name index name. · Column serial number in Seq_in_index, starting from 1. · Column_name column name. · Estimate the number of unique values in the Collation CardinalityMySQL index. You can update analyze table or myisamchk-a by running analyze table. The base number is counted based on the statistical data stored as an integer. Therefore, this value is not required to be accurate even for small tables. The larger the base, the larger the chance for MySQL to use the index for union. · Sub_part: If a column is partially indexed, it is the number of indexed characters. If the entire column is indexed, the value is NULL. · Null: If the column contains NULL, YES is contained. If NO, the column contains NO. · Index_type

Unique index in mysql

Ignore keyword ~ Add it after insert.
Insert ignore ....