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mySQL outer join

I have 2 tables for which I need to run a query on

Table1 has 2 fields: l_id, and name

Table2 also has 2 fields: l_id, and b_id

I need to run a query to get the "name" and "l_id" for all the entries i开发者_高级运维n table1 that do not have an entry in table2 for a given b_id.

Hope this makes some sense


select t1.*
from Table1 t1
left outer join Table2 t2 on t1.l_id = t2.l_id
    and t2.b_id = @SomeValue
where t2.l_id is null


You can use an outer join, but I find a sub-query is a little more straightforward. In your case selecting everything from table1 that does not have an id in table2. Reads better...

SELECT * FROM table1 WHERE l_id NOT IN (SELECT l_id FROM table2);
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