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Wildhoney · 12-15-2007, 06:11 PM

Just remember to join on indexes. Don't join on non-indexes as it will become painfully slow.

LEFT JOIN basically says if the data is in table 1, but might not be in table 2 - if it's not in table 2, add a null and still pull table 1's data.

RIGHT JOIN is the reverse of the aforementioned.

INNER JOIN is when you only want to pull data from table 1 and table 2 when there's a valid JOIN on an index.

12-15-2007, 06:11 PM	#4 (permalink)
Wildhoney La Vida es Sueño Join Date: Sep 2007 Location: Oldham Posts: 2,280 Thanks: 90	Just remember to join on indexes. Don't join on non-indexes as it will become painfully slow. LEFT JOIN basically says if the data is in table 1, but might not be in table 2 - if it's not in table 2, add a null and still pull table 1's data. RIGHT JOIN is the reverse of the aforementioned. INNER JOIN is when you only want to pull data from table 1 and table 2 when there's a valid JOIN on an index. __________________ The man who comes back through the Door in the Wall will never be quite the same as the man who went out.