Temporary tables and in-memory use

Marios Vodas <mvodas@gmail.com> writes:

If I'm not wrong, temporary tables stay in memory if they do not go over
temp_buffers limit (e.g. if temp_buffers is 2GB and the size of the table is
300MB the table will remain in memory).
What if a column is variable length (e.g. text), how does this column stay
in-memory since it should be stored in TOAST?

Well, the toast table is also temp, so it'll get cached in temp_buffers
as well, as long as it fits.

When I build a GiST index on a temporary table does the index stay in memory
as well?

Same answer.

Keep in mind that temp_buffers is per process, not global. Just as with
work_mem, you need to be careful about setting it sky-high.

regards, tom lane

Thank you. The setup is intended for one user environment for complex
queries and operations that's why I wrote 2GB temp_buffers!
Thank you again, I really appreciate it.
Marios