Do indexes help a mysql MEMORY table? -



Do indexes help a mysql MEMORY table? -

i optimizing 3 gb table memory table in order analysis on it, , curious if adding indexes help memory table. since info in memory anyway, redundant?

no, they're not redundant.

yes, go on utilize indexes.

the speed of access memory table on smaller tables non-indexed column may seem identical indexed ones due how fast total table scans can in memory, table grows or bring together them create larger result sets there difference.

regardless of storage method engine uses (disk/memory), proper indexes improve performance long storage engine supports them. how indexes implemented may vary, know implemented in table types memory, innodb, , myisam. btw: default method indexes in memory tables hash instead of b-tree.

also, don't recommend coding storage engine. what's memory table today may need changed innodb tomorrow--the sql , schema should stand on it's own.

mysql memory optimization

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