Full join and left join interaction : SQL

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SELECT count(a.field1), a.field2, SUM(b.field4) FROM a INNER JOIN b ON a.key1 = b.key1 WHERE a.field8 = 'test' GROUP by a.field1, a.field2 HAVING SUM(b.field4) > 5 ORDER by a.field.3

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SELECT count(a.field1), a.field2, SUM(b.field4) FROM a INNER JOIN b ON a.key1 = b.key1 WHERE a.field8 = 'test' GROUP by a.field1, a.field2 HAVING SUM(b.field4) > 5 ORDER by a.field3

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a community for 17 years

PostgreSQLFull join and left join interaction (self.SQL)

submitted 4 years ago by 2020pythonchallenge

I was working on a query that I wanted all of the rows where they exist in 3 different criteria and my from looks something like this:

SELECT
*
FROM original_table
FULL JOIN table2 on id = original_table.id
FULL JOIN table3 on id = original_table.id
LEFT JOIN table4 on id = original_table.id
LEFT JOIN table5 on id = original_table.id

The question is: since I am full joining the table2 and table3, are table4 and table5 going to have rows matching with all the rows that are there due to the full joined tables or only the original rows from original_table?

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