Feb
1
Posted by john in mysql
The other day I needed to compare two tables and see what data was in one but not in the other.
table_a is my main table that I want to update and table_b is my storage table that I have my updates in. The query below will return all records that are in table_b, but no in table_a.
SELECT table_b.* FROM table_b
LEFT JOIN table_a ON table_b.id = table_a.id
WHERE table_a.item_id IS NULL
The you can take those results and use them to INSERT the missing records.
This is the best way I can think of. If anyone has a better way, please leave a comment on how you would recommend.
February 8th, 2007 at 4:57 pm
This is palmetto from digg.. thanks for the info about myphpadmin and mysql.
@palmetto - if you’ve already got a site and a company with PHP & MySQL hosting your site, hop on over to http://www.linein.org/blog/ and post a comment with your email address. I’d be more than happy to help. Both are really easy to setup and get started.
thanks for the help.. I will be learning now.
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