Combine statement but only need to get data based on WHERE column of table is empty
I have this query and only want to get records with a specific column empty ( volunteers_2009.venue_id
)
Table volunteers_2009
, column I'm looking to see if it's empty:venue_id
Here's the current request:
SELECT volunteers_2009.id, volunteers_2009.comments,
volunteers_2009.choice1, volunteers_2009.choice2, volunteers_2009.choice3,
volunteers_2009.lname, volunteers_2009.fname, volunteers_2009.venue_id,
venues.venue_name
FROM volunteers_2009 AS volunteers_2009
LEFT OUTER JOIN venues ON (volunteers_2009.venue_id = venues.id)
ORDER by $order $sort
I am trying to do this:
SELECT volunteers_2009.id, volunteers_2009.comments,
volunteers_2009.choice1, volunteers_2009.choice2, volunteers_2009.choice3,
volunteers_2009.lname, volunteers_2009.fname, volunteers_2009.venue_id,
venues.venue_name
FROM volunteers_2009 AS volunteers_2009
LEFT OUTER JOIN venues ON (volunteers_2009.venue_id = venues.id)
ORDER by $order $sort
WHERE volunteers_2009.venue_id == ''
How do I display only records containing an empty column ( venue_id
) in a table ( volunteers_2009
)?
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WHERE clause doesn't work in your second query. It must come before the ORDER BY clause.
Also, I don't think you have empty id places. Perhaps you really want:
SELECT volunteers_2009.id, volunteers_2009.comments,
volunteers_2009.choice1, volunteers_2009.choice2, volunteers_2009.choice3,
volunteers_2009.lname, volunteers_2009.fname, volunteers_2009.venue_id,
venues.venue_name
FROM volunteers_2009
LEFT JOIN venues ON venue_id = venues.id
WHERE venues.id IS NULL
ORDER BY $order $sort
This will only return volunteers_2009 records that do not match locations.
Or that:
SELECT volunteers_2009.id, volunteers_2009.comments,
volunteers_2009.choice1, volunteers_2009.choice2, volunteers_2009.choice3,
volunteers_2009.lname, volunteers_2009.fname, volunteers_2009.venue_id,
venues.venue_name
FROM venues
LEFT JOIN volunteers_2009 ON volunteers_2009.venue_id = venues.id
WHERE volunteers_2009.venue_id IS NULL
ORDER BY $order $sort
to find places without volunteers.
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