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I have a MySQL database ver 5.1. I have two tables Table_A will always keep the records in it. Table_B will be used to only compare the differences. Is there a MySQL query function via PHP that will compare the rows and tell me what rows are missing on Table_B.

Table_A

user    name
 1      bob
 1      joe
 1      sally
 1      matt

Table_B

user    name
 1      bob
 1      joe
 1      sally
 1      john

When the PHP query was run how would I compare Table_A vs Table_B? All I need is to tell me that matt no longer exists and it will add john to Table_A.

What would be the best way to do this?

Thanks.

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SELECT name FROM Table_A WHERE name NOT IN (SELECT name FROM Table_B)
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3 Comments

I switched user to name and it worked. Then I guess I would just run the query back words to insert any new names then.
Worked like a charm for both ways of doing it. Thank you!
Right, it should have been name - sorry and changed.

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