[eluser]Jay Turley[/eluser]
[quote author="mikeyhell" date="1205813256"]I'm rescripting and application and ran into an sql statement that's stumped me. Can someone help me understand what's going on here:
Code:
SELECT hotlead_flag, ve.*
FROM vendor_email_new ve
JOIN vendor_new using (email)
WHERE sent_email is null
[/quote]
it is selecting
hotlead_flag from the
vendor_new table, and then selecting everything (
ve.*) from the
vendor_email_new table which has been aliased as
ve. The tables are joined on the
email column and the final criteria is if the
vendor_new.sent_email column is null.
You can think of it this way (though I would probably enumerate the columns in the vendor_email_new table instead of using *):
Code:
SELECT
vn.hotlead_flag, ve.*
FROM
vendor_email_new ve
JOIN
vendor_new vn
ON
ve.email = vn.email
WHERE
vn.sent_email IS NULL
