Using Temp Tables in SSIS

Temporary tables are created in the TempDB database, which persists for a particular session. The objective is to maintain that session, until the temp table information is used and dump the data into a physical table. To maintain a session in SSIS, there is a ‘Retain Same Connection’ property of the Connection Manager. If we need to maintain a single session, we have to mark this property ‘True’.

Let us start with a sample package. I will create the package step by step.

1. Create two Connection manager’s – ‘Server 1’ and ‘Server 2’. Server 2 will be the server where we need to create the temp table using Server 1 and thereafter use that temp table in the queries executed on Server2.

   

2. Set the RetainSameConnection property of the Server 2 to True.

   

3. Drag an Execute SQL Task in the Control Flow.

   

4. Insert the SQL Statement create table #temptestusers (id int) inside the SQLStatement field in the Execute SQL Task Editor. This will create the temp table. Also set the Connection to Server2.

   

5. Drag a DFT below the Execute Sql Task, which will insert the data in the temp table.

   

6. Drag OLEDB source and OLEDB destination in the DFT

   

7. In the OLEDB Source, enter the query

   SELECT 1 as id
   UNION ALL
   SELECT 2 as id
   

   

8. The next step is to connect the ‘OLEDB Destination’.  Our objective is to load the data into a temporary table. However, you will not be directly able to select the temp table in Design mode. So, we will create a new temp table, if you do not have table creation rights, you can create a global temporary table and select that. Here, we will create a TestDestination table and map the Source and Destination columns :

   

9. Now, as we mapped it in design mode, we can modify it later to use the Temporary table. To use Temporary table in the Destination, follow the below steps:

   a) Go to SSIS Menu > Select Work Offline

   

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   b) Select the OLEDB Destination > Properties > Set the OpenRowset property to use the temporary table ‘dbo.[#temptestusers]’

   

10. Now, we can verify the data in the temp table. First of all Deselect the ‘Work Offline’ mode, which was used in above step. To verify we will add other Data Flow Task which will query this temp table created above and will load the data from it to another server table. Add a  second DFT, ‘Use the temp table and insert in physical table’.

    

11. Add OLEDB Source and Destination in the new DFT. Use SQL to select the rows from temp table select id from #Temptestusers.

    

12. You will not be able to select it in design mode, as the temp table does not exist right now. So, first select from any other table and start the DFT working, then follow the same steps as shown above. ‘Go to the SSIS menu -> Select Work Offline -> Go to the OLEDB Source Properties -> Select SQLCommand and modify the query in the String Value editor to use the temp table.

    

13. Next in the OLEDB Destination, select the server on which you have permission to create table, in this case I am selecting Server1.

    

14. That’s it. The temporary table package is now completed. We can run the package and review the flow of data.

    

    

    2 Rows transferred into #temptestusers table.

    

    2 rows transferred to the physical table from temp table.

Hopefully this will help anyone to make use of temporary tables in their design. The only thing is to make sure of is that we set ‘Work Offline’ flag on/off in the package.

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