Question

Given two tables


T1
key   |  value
---------------
1       | a
2       | b
4       | c
---------------

T2
key   |  value
---------------
2       | a
3       | b
5       | c
---------------

Which one of the following queries will return more records in the result set than all others?

Cosmo · Accepted Answer

Cross join (or sometimes called cartesian join) will return all possible combinations of records from first table with records from second table.

Cosmo · Accepted Answer

SELECT T1.*, T2.* FROM T1, T2

Cosmo · Answer

SELECT T1.*, T2.* FROM T1 INNER JOIN T2 ON T1.key = T2.key

Cosmo · Answer

SELECT T1.*, T2.* FROM T1 LEFT OUTER JOIN T2 ON T1.key = T2.key

Cosmo · Answer

SELECT T1.*, T2.* FROM T1 RIGHT OUTER JOIN T2 ON T1.key = T2.key

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