MySQL keys: PRIMARY KEY, FOREIGN KEY, KEY -- what is "KEY"? -

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looking @ "mysqldump -d" , see key key, not "primary key" or "foreign key"

what key?

example:

create table if not exists `table_001` (   `col_001` int(256) not null,   `col_002` int(256) not null,   `col_003` int(256) not null,   `col_004` int(256) not null,   `col_005` int(256) not null,   `col_006` int(256) not null,   `col_007` int(256) not null,   `col_008` int(256) not null,   `col_009` int(256) not null,   `col_010` int(256) not null,   `col_011` int(256) not null,   `col_012` int(256) not null,   primary key  (`col_001`),   key `col_002` (`col_002`,`col_003`),   key `col_012` (`col_012`), ) engine=myisam default charset=utf8;

also, when i'm create new version of table, changing myisam innodb require additional changes besides "engine=myisam" "engine=innodb"?

key alternative syntax index declaration. create table statement includes creating 2 indexes, on col_002 , col_012 separately.

...when i'm create new version of table, changing myisam innodb require additional changes besides "engine=myisam" "engine=innodb"?

no, should fine aware can't use mysql's native full text search (fts) on tables using innodb engine -- have myisam before can full text index columns in them.


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