MYSQL compare 2 tables

Posted on 2014-08-11
Last Modified: 2014-08-11

I have property listings in one table "res" and map coordinates for property listings in "map" table.

I have a geocoder configured but I only want to geocode property listings that do not already have a record in the map table.

So my question is how would I form a query to check?

Both tables have field "ListID" as PK

Question by:Bang-O-Matic
    LVL 142

    Accepted Solution

    Something like this should do
    Select res.*
    From res
    Left  join map
     On =
    Where is null

    Author Closing Comment

    Perfect! thank you!

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