Question

if I do:

select * from tempdb.sys.tables

I will see all the temporary tables in the system, however that view does not have information about which connection/user each table belongs to. I’m interested in finding only the tables I’ve created on my current connection. Is there a way to do this?

thanks – e

p.s. yes, I could try reading each table listed with the notion that those that succeed should prove to be mine (on recent versions one can’t read other connections’ tables) but that is too costly an approach since there may be thousands of tables on the system

p.p.s. I did read Is there a way to get a list of all current temporary tables in SQL Server? which asks the right question but did not get a good answer

Answer 1

Assuming you don’t name your #temp tables with three consecutive underscores, this should only pick up your #temp tables. It won’t, however, pick up your table variables, nor can you change this code somehow to pick the tables on someone else’s connection – this only works because OBJECT_ID('tempdb..#foo') can only return true for a table in your session.

SELECT 
  name = SUBSTRING(t.name, 1, CHARINDEX('___', t.name)-1),
  t.[object_id]
FROM tempdb.sys.tables AS t
WHERE t.name LIKE '#%[_][_][_]%'
AND t.[object_id] = 
  OBJECT_ID('tempdb..' + SUBSTRING(t.name, 1, CHARINDEX('___', t.name)-1));

You might also be interested in space used by each of these tables (at least for the heap or clustered index), e.g.:

SELECT 
    name = SUBSTRING(t.name, 1, CHARINDEX('___', t.name)-1),
    t.[object_id], 
    p.used_page_count, 
    p.row_count
FROM tempdb.sys.tables AS t
INNER JOIN tempdb.sys.dm_db_partition_stats AS p
ON t.[object_id] = p.[object_id]
WHERE t.name LIKE '#%[_][_][_]%'
AND p.index_id IN (0,1)
AND t.[object_id] = 
    OBJECT_ID('tempdb..' + SUBSTRING(t.name, 1, CHARINDEX('___', t.name)-1));

You could extend that to show total space for all indexes. I didn’t bother aggregating per partition since these are #temp tables.