How to create an index in mysql

Index is a very important thing in MySQL. Now I will take you to learn how to create an index in MySQL.

It is divided into five indexing methods:

1. Add PRIMARY KEY (primary key index)

mysql>ALTER TABLE `table_name` ADD PRIMARY KEY ( `column` )

2. Add UNIQUE (unique index)

mysql>ALTER TABLE `table_name` ADD UNIQUE (
`column`
)

3. Add INDEX (normal index)

mysql>ALTER TABLE `table_name` ADD INDEX index_name ( `column` )

4. Add FULLTEXT (full text index)

mysql>ALTER TABLE `table_name` ADD FULLTEXT ( `column`)

5. Add multi-column index

mysql>ALTER TABLE `table_name` ADD INDEX index_name ( `column1`, `column2`, `column3` )

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