topic Left join with two key fields in QlikView

Left join with two key fields

Tue, 05 Jun 2012 14:03:00 GMT

Hi,

Can anyone explain how Qlikview performs left join of two tables when they share two fieldnames in common?

Many thanks,

Murali

Left join with two key fields

vincent_ardiet — Tue, 05 Jun 2012 14:52:13 GMT

Hi,

It works like in SQL.

The two columns must have the same value to perform the join.

Regards,

Vincent

Re: Left join with two key fields

Tue, 03 Jul 2012 11:09:43 GMT

Hi Vincent,

Will this work for all other types of join?

Re: Left join with two key fields

vincent_ardiet — Wed, 04 Jul 2012 07:42:42 GMT

Hi Kiran2in,

What do you mean ? Inner join, right outer join and full outer join ?

Here are some details:

- Using the key word JOIN in QV is the same as FULL OUTER JOIN in SQL ;

- LEFT JOIN in QV is the same as LEFT OUTER JOIN in SQL ;

- RIGHT JOIN in QV is the same as RIGHT OUTER JOIN in SQL ;

- INNER JOIN in QV is the same as INNER JOIN in SQL ;

So, the big difference is that, in QV, default joins are FULL OUTER JOIN, but, in SQL, default joins are INNER JOIN.

Then, in SQL you can specify on which columns you want to join either from the right table, either from the left table. But QV automaticaly joins columns with the same name and like in SQL, the combination of all values from those columns have to be the same in the left table and in the right table to perform the join (whatever type of join you choose).

Regards,

Vincent

Re: Left join with two key fields

Tue, 18 Sep 2012 06:12:19 GMT

Hi Vincent,

Thanks for clarification.