sam marshall ed00d67c99 MDL-60174 core_dml: get_recordset on Postgres eats all the RAM
On Postgres, get_recordset_sql loads all the results into memory
(within the Postgres library, which doesn't count towards the PHP
memory limit, but does count towards making your server run out of
memory) as soon as the query completes.

This commit changes the code to use cursors, which in Postgres
allow the results to be returned in smaller chunks (by default
100,000 rows).
2017-11-27 11:10:29 +00:00
..