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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