topic Drop table only if it exists in QlikView

Drop table only if it exists

Mon, 15 Mar 2010 14:49:40 GMT

Hello experts,

In a .qvw I created a QV table inside a condition statement.

Opening binary the above one in another .qvw file, I need to check if the QV table has been created.

Is there a way to check if a QV table exists before calling a drop table statement ?

Thanks in advance.

Best regards

Drop table only if it exists

Miguel_Angel_Baeyens — Mon, 15 Mar 2010 15:10:35 GMT

Hello,

There is a system field called $Table which stores all actually loaded tables, so checking this field (with peek(), for exmple) for that table value should work for you.

Hope that helps.

Drop table only if it exists

lblancher — Mon, 15 Mar 2010 15:14:22 GMT

Hi,

If the table has a key column, you can do something like.


LET IsFieldAvailable = peek('keyColumn');
IF IsFieldAvailable THEN
 DROP TABLE myTable;
END IF;

Lucas Blancher

BizXcel Inc.

Drop table only if it exists

Mon, 15 Mar 2010 17:47:26 GMT

The following should work:

if noOfRows('tablename') > 0 then
drop table tablename;
end if

regards
/Fredrik

Drop table only if it exists

disqr_rm — Mon, 15 Mar 2010 20:33:34 GMT

Other way is to set the errormode variable appropriately so in case of error, it skips it and not terminate. Something like:

Set ErrorMode = 0; //Set it to skip error

DROP Table xyz;

Set ErrorMode = 1; //Set it back to standard

Drop table only if it exists

Miguel_Angel_Baeyens — Tue, 16 Mar 2010 08:32:50 GMT

Here you are another one, maybe more practical, using system function TableName()

If (len(TableName('YourTable')) > 0) Then Drop Table YourTable; End If

Re: Drop table only if it exists

Anonymous — Wed, 21 Oct 2015 19:36:52 GMT

great solution but small correction:

If (len(TableNumber('YourTable')) > 0) Then Drop Table YourTable; End If

Re: Drop table only if it exists

janderooij — Tue, 24 Mar 2020 09:49:28 GMT

Hello ,

The solution set errormode = 0 worked for me!

Other solutions fail because the table can't be checked on rows etc while it is simply not existing!

Thanks!