MySQL 8 Administrator???s Guide

Creating an INDEX command

The following command enables the user to add indexes into an existing table. This command is also used with CREATE TABLE and ALTER TABLE to create indexes:

CREATE [UNIQUE|FULLTEXT|SPATIAL] INDEX index_name [index_type] ON tbl_name (index_col_name,...) [index_option] [algorithm_option | lock_option] ...index_col_name: col_name [(length)] [ASC | DESC]index_option: KEY_BLOCK_SIZE [=] value | index_type | WITH PARSER parser_name | COMMENT 'string' | {VISIBLE | INVISIBLE}index_type: USING {BTREE | HASH}algorithm_option: ALGORITHM [=] {DEFAULT|INPLACE|COPY}lock_option: LOCK [=] {DEFAULT|NONE|SHARED|EXCLUSIVE}

Using col_name(length) syntax, the user is able to specify an index prefix length, which will consider only a ...