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SIMPLE SQL - INNER JOIN / GROUP - return NULL values in results list

Simple one really - I have some SQL, there is an inner join and a group by the inner join eg:

select count(*) AS Total, myTable.myField FROM myTable INNER JOIN myJoinedTable ON myTable.myField = myJoinedTable.myField GROUP BY myJoinedTable.fieldToGroupBy

At the moment it returns:

a: 3
b: 1
c: 8

etc - but if there are any NULL values in the main table in fieldToGroupBy they get ignored. I cannot think of / find the syntax to just return another row for any null values (or values that do not match the joined table).

can any one fill me in?

Thanks!...

peter57r

Hello niico,

> etc - but if there are any NULL values in the main table in fieldToGroupBy
fieldToGroupBy would appear to be in the joined table, not the main table

> they get ignored. I cannot think of / find the syntax to just return
> another row for any null values (or values that do not match the joined table).

I don't think I understand what you expect here

For values to be returned from an inner join, there must be a matching record on both sides of the join.
If there is no record in one of the tables then no values will be returned.

The alternative join types would be a left join or a right join.

In your SQL code then instead of 'FROM myTable INNER JOIN myJoinedTable '
you could have
FROM myTable Left JOIN myJoinedTable
This would return values from myTable whether or not there was a matching record in myJoinedTable.

Similarly
FROM myTable Right JOIN myJoinedTable

would return all records from myJoined tabel irrespective of whether there was a matching record in myTable.

Perhaps one of these is what you need?

Pete

niico

ASKER

>>fieldToGroupBy would appear to be in the joined table, not the main table

sorry you're right - i meant myField

<yes actually I over simplified - there are two joins.

I'll go away and think about exactly what Im trying to do and come back to you - sorry for the vague question...

gita_borad

use a left join?

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niico

ASKER

hi

sorry about the delay - this thing ended up getting postponed and havent had a chance to look again.

No objection to giving points to lfs.

thanks!...