If i inner join to a table that has been left joined, do I flatten the outer to an inner join?
You can assume, in the following example, that the tables all have a column called ID, and another varying-name column that is unique between tables:
what do I see?Code:SELECT id, a.colA, b.colB, c.colC FROM a LEFT OUTER JOIN b ON b.id = a.id INNER JOIN c ON c.id = b.id
1) colA no nulls, colB nulls, colC nulls
Total rows: count(*) of a
2) colA, colB and colC all no nulls
Total rows: lesser of (count(*) of b, count(*) of c)
Cheers




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