Introduced by the fix for #5597.

Thanks for reporting.

Do you have a suggestion regarding what's the correct query to do instead?

also cc @gordthompson

Sorry, should have included the suggested fix. I use something like this, which works for both temp tables and physical tables.

    db = 'tempdb.' if tname.startswith('#') else ''
    t_id, = con.execute(f"select object_id('{dbname}dbo.{tname}')").fetchone()
    return t_id is not None

Not sure if there's some other preferred method.

Gord Thompson has proposed a fix for this issue in the master branch:

Fix has_table() to exclude other sessions' temp tables https://gerrit.sqlalchemy.org/c/sqlalchemy/sqlalchemy/+/3014

I noted on the gerrit that the above fix should not apply to global temporary tables that start with "##".

@zzzeek I think the attached fix works for global temp tables. Temp tables from the current session and ##global temp tables will both have non-null object_ids, so this version of has_table will return True for both of them, as expected. And the _temp_table_name_like_pattern logic is unaffected.

@gordthompson I also noticed when looking into this that the _temp_table_name_like_pattern doesn't seem to be quite right. The unquoted underscore is a single-character wildcard in a like pattern, so '#tmp___%' will also match a table named '#tmp123'. The object_id logic should do the right thing, so I think the proposed fix also takes care of that, just something to be aware of.

@zzzeek I think the attached fix works for global temp tables. Temp tables from the current session and ##global temp tables will both have non-null object_ids, so this version of has_table will return True for both of them, as expected. And the _temp_table_name_like_pattern logic is unaffected.

oh, good idea.

The unquoted underscore is a single-character wildcard in a like pattern

Good point. Thanks for mentioning it!