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Databases Querying Relational Databases Joining Table Data with SQL JOIN Queries

Posted by Shreemangal Sethi
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Shreemangal Sethi
Full Stack JavaScript Techdegree Student 15,552 Points

INNER JOIN 3 Table and Multiple Columns.

There are 3 tables and Multiple Columns i am not sure how to use INNER JOIN twice after FROM keyword.

2 Answers

Sean T. Unwin
Sean T. Unwin
28,690 Points
Sean T. Unwin
Sean T. Unwin
28,690 Points

Here's a pseudo-code example:

SELECT
T1.field1
T2.field2
T3.field3
FROM T1
INNER JOIN T2 ON (T1.someId = T2.someId)
INNER JOIN T3 ON (T2.someOtherId = T3.someOtherId) 
-- The second JOIN could also match T1.someId if the same column is in T3
Shreemangal Sethi
seal-mask
.a{fill-rule:evenodd;}techdegree
Shreemangal Sethi
Full Stack JavaScript Techdegree Student 15,552 Points
Shreemangal Sethi
.a{fill-rule:evenodd;}techdegree
Shreemangal Sethi
Full Stack JavaScript Techdegree Student 15,552 Points

Thanks! Got it.