How long will a temporary MEMORY table persist if I don't drop it (MySQL) [closed]

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I'm using a recursive stored procedure in MySQL to generate a temporary table called id_list, but I must use the results of that procedure in a follow up select query, so I can't DROP the temporary table within the procedure...

BEGIN;

/* generates the temporary table of ID's */
CALL fetch_inheritance_groups('abc123',0);

/* uses the results of the SPROC in the WHERE */
SELECT a.User_ID
FROM usr_relationships r 
INNER JOIN usr_accts a ON a.User_ID = r.User_ID 
WHERE r.Group_ID = 'abc123' OR r.Group_ID IN (SELECT * FROM id_list) 
GROUP BY r.User_ID;

COMMIT;

When calling the procedure, the first value is the top ID of the branch I want, and the second is the tier which the procedure uses during recursions. Prior to the recursive loop it checks if tier = 0 and if it is it runs:

DROP TEMPORARY TABLE IF EXISTS id_list;
CREATE TEMPORARY TABLE IF NOT EXISTS id_list (iid CHAR(32) NOT NULL) ENGINE=memory;

So my question is: If I don't DROP the temporary MEMORY table at the end of the procedure, or within my transaction, how long will that table persist in memory? Is it automatically dropped once the session ends, or will it remain in memory as long as the connection is open?

**N.B. The obvious answer might be to drop the temp table prior to the commit statement, but lets assume for a moment that I can't do that.*

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A more detailed answer to this question can be found here: https://dba.stackexchange.com/questions/57971/how-long-will-a-temporary-memory-table-persist-if-i-dont-drop-it-mysql so I've voted to close this question.

Answer 1

Per the manual, the temporary table is dropped automatically when the connection is closed (emphasis mine):

Temporary Tables

You can use the TEMPORARY keyword when creating a table. A TEMPORARY table is visible only to the current connection, and is dropped automatically when the connection is closed.

Answer 2

Temporary tables are in the scope of database connection