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Editorial Team
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Asked: 2026-06-15T17:43:21+00:00

Lets say i have this sample table: CREATE TABLE `users` ( `id` INT NOT

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Lets say i have this sample table:

CREATE  TABLE `users` (
   `id` INT NOT NULL AUTO_INCREMENT ,
   `name` VARCHAR(512) NULL ,
   `lastname` VARCHAR(512) NULL ,
   `country` VARCHAR(256) NULL ,
   `tags` VARCHAR(512) NULL ,
PRIMARY KEY (`id`) );

Basically the “tags” column is just key words that are set for the user

Now what i want to do is be able to search for a user based on the name and tags
To have fast search, i would had to create an index on “name” and “tags”

So to create index should i do:

ALTER TABLE `vidhucr1_serverlist`.`new_table` 
ADD INDEX `INDEX` (`name` ASC, `tags` ASC) ;

or

ALTER TABLE `vidhucr1_serverlist`.`new_table` 
ADD INDEX `INDEX1` (`name` ASC) 
, ADD INDEX `INDEX2` (`tags` ASC) ;
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1 Answer

  1. Editorial Team

    Having a single index (name, tags) should be better as long as your query filters names and tags. If your query should omit tags, the index would be useless (last statement under example 1). Also, I hope that you do not have multiple “tags” in the tags field.

    Example 1 – Composite Index

    Indexes: INDEX (name, tags)

    Index would be used for SELECT ... WHERE name = '...' AND tags = '...' or SELECT ... WHERE tags = '...' AND name = '...'

    | ID | SELECT_TYPE | TABLE | TYPE | POSSIBLE_KEYS |   KEY | KEY_LEN |         REF | ROWS |       EXTRA |
--------------------------------------------------------------------------------------------------------
|  1 |      SIMPLE | users |  ref |         INDEX | INDEX |    1536 | const,const |    1 | Using where |

    Index would be used for SELECT ... WHERE name = '...'

    | ID | SELECT_TYPE | TABLE | TYPE | POSSIBLE_KEYS |   KEY | KEY_LEN |   REF | ROWS |       EXTRA |
--------------------------------------------------------------------------------------------------
|  1 |      SIMPLE | users |  ref |         INDEX | INDEX |     768 | const |    1 | Using where |

    No index used for SELECT ... WHERE tags = '...'

    | ID | SELECT_TYPE | TABLE | TYPE | POSSIBLE_KEYS |    KEY | KEY_LEN |    REF | ROWS |       EXTRA |
----------------------------------------------------------------------------------------------------
|  1 |      SIMPLE | users |  ALL |        (null) | (null) |  (null) | (null) |    1 | Using where |

    Example 2 – Two Single Indexes

    Indexes: INDEX1 (name), INDEX2 (tags)

    Both indexes used for SELECT ... WHERE name = '...' AND tags = '...'

    | ID | SELECT_TYPE | TABLE | TYPE | POSSIBLE_KEYS |    KEY | KEY_LEN |   REF | ROWS |       EXTRA |
---------------------------------------------------------------------------------------------------
|  1 |      SIMPLE | users |  ref | INDEX1,INDEX2 | INDEX1 |     768 | const |    1 | Using where |

    INDEX1 used for SELECT ... WHERE tags = '...'

    | ID | SELECT_TYPE | TABLE | TYPE | POSSIBLE_KEYS |    KEY | KEY_LEN |   REF | ROWS |       EXTRA |
---------------------------------------------------------------------------------------------------
|  1 |      SIMPLE | users |  ref |        INDEX1 | INDEX1 |     768 | const |    1 | Using where |

    INDEX2 used for SELECT ... WHERE name = '...'

    | ID | SELECT_TYPE | TABLE | TYPE | POSSIBLE_KEYS |    KEY | KEY_LEN |   REF | ROWS |       EXTRA |
---------------------------------------------------------------------------------------------------
|  1 |      SIMPLE | users |  ref |        INDEX2 | INDEX2 |     768 | const |    1 | Using where |
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