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SQL JOIN: is there a difference between USING, ON or WHERE?
Which is better:
SELECT `sheet_data`.*
FROM `clip`, `sheet_data`
WHERE `clip`.`mrecord`='8' AND `clip`.`data`=`sheet_data`.`id`
or
SELECT `sheet_data`.*
FROM `clip` INNER JOIN `sheet_data`
ON `clip`.`data`=`sheet_data`.`id`
WHERE `clip`.`mrecord`='8'
and why?
In older days, the first was faster, but this is not true anymore. I personally think the INNER JOIN is better, because it is more readable. It shows better the relations between the table. You got those relations in the join, and you do the filtering in the WHERE clause. This separation makes the query more readable. But this is a matter of personal taste.