In inner join it returns only the matching rows of joining table but in full outer join it returns matching rows and include all the unmatched row from both table look as following exemple if we are joining two table one have 5 rows and other have 10 rows and three rows in each tables are maching the condition then result according to no. of rows will be in inner join: only three rows, in full outer join: 3+2+7 (3 matched rows+2 unmatched rows from first table + 7 unmatched rows from second table).
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