How exactly is the MySQL index classified?

see some materials:

The index of

mysql is divided into single-column index (primary key index, unique index, general index) and combined index.

single-column index: an index contains only one column, and a table can have multiple single-column indexes.

Composite index: a composite index contains two or more columns,

and what kind of full-text index do we often talk about?

and I tried to build a composite index, a combination of name and age fields:

ALTER TABLE `user` ADD INDEX index_titme_time (name,age)

after success, I Navicat to see the following figure:

is he a general index or a composite index at this time?

Mysql

Oct.20,2021

answer the following questions first. index_titme_time is a composite index and a common index

whether an index is a primary key index, a unique index, or a normal index has nothing to do with whether the index is a single column or a combination. If an index contains only one column, it is a single-column index, otherwise it is a composite index. As to whether it is a primary key, a unique index or a normal index, it is the

that needs to be specified in the creation statement.


										
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						MySQL Query :  SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5 
 MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1e59d5d-66f05.MAI); waiting for someone to free some space... (errno: 28 "No space left on device") 
 MySQL Errno : 1021 
 Message :  Disk full (/tmp/#sql-temptable-64f5-1e59d5d-66f05.MAI); waiting for someone to free some space... (errno: 28 "No space left on device") 
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