Getting row count for a table in MySQL?
Solution 1
In MyISAM
, this query:
SELECT COUNT(*)
FROM TABLE_NAME
is instant, since it's kept in the table metadata, so it's almost free to issue this query and it will always get the correct result.
In InnoDB
, this query will count rows one-by-one which could take some time.
So if you don't need exact value of COUNT(*)
, you may query INFORMATION_SCHEMA
.
Solution 2
I'd also consider using SQL_CALC_FOUND_ROWS
and SELECT FOUND_ROWS()
if you find COUNT(*)
too slow.
Admin
Updated on July 09, 2022Comments
-
Admin almost 2 years
Can anyone tell me which is he better appraoch in MySQL whin it comes to finding the row count of a table: is it better to do
SELECT COUNT(*) FROM TABLE_NAME
or to look up the row count in the table
TABLE
in theINFORMATION_SCHEMA
?This would be a frequent operation for calculating pagination counts for pages?
I should add that tables will only have a few thousand rows at most.
Thanks
Martin O'Shea.
-
Admin almost 15 yearsI think that given that I need to calculate pagination using row count / pagination count, on InnoDB tables the best way is to use the INFORMATION_SCHEMA. Counting would only take milliseconds but that's still an overhead if several users are accessing the same table for browsing.