what are join types
INNER JOIN:
is used when retrieving data from multiple
tables and will return only matching data.
LEFT OUTER JOIN:
is used when retrieving data from
multiple tables and will return
left table and any matching right table records.
RIGHT OUTER JOIN:
is used when retrieving data from
multiple tables and will return right
table and any matching left table records
FULL OUTER JOIN:
is used when retrieving data from
multiple tables and will return both
table records, matching and non-matching.