How to get the size of the result of a SQL query? How do you get the size (in bytes) of the result of a SQL query, in MySQL 5.6?

EXPLAIN will return the number of fetched rows, but not their size.

My aim is to evaluate common queries to know a lower bound value for query_cache_limit so that they can be served by the Query Cache.
There is no way.


EXPLAIN gives you an estimation; do not count on it being exact.
The number of bytes in a resultset is not directly available.  And attempts to estimate will be fraught with errors.
The structure of the QC is another variable -- there is overhead to take into account.
Since every row for a table in the QC is purged when any write to the table occurs, the QC is rarely useful at all.