![]() ![]() Consider the following example: SELECT *Īlthough the ANSI standard didn’t specify outer joins at the time, most RDBMS supported them in one way or another. To perform an INNER JOIN, you only needed to add the JOIN predicate as part of the WHERE clause. The ANSI syntax for a CROSS JOIN operator was to list the sets in the FROM clause using commas as separators. Up until SQL Server version 2008 R2, SQL Server also supported the old style JOIN syntax including LEFT and` RIGHT OUTER JOIN`. In that case, NULL is assigned to all columns of. OUTER APPLY - Similar to a LEFT OUTER JOIN in the sense that rows from are returned even if the sub query for produces an empty set. CROSS APPLY - Similar to a CROSS JOIN in the sense that every row from is matched with every row from. This functionality isn’t possible with any type of standard JOIN operator. However, APPLY operators enable the creation of a correlation between and such as that may consist of a subquery, a VALUES row value constructor, or a table valued function that is evaluated for each row of where the query can reference columns from the current row in. SQL Server also supports the APPLY operator, which is somewhat similar to a join. FULL OUTER JOIN ON - Designates both sets as reserved and adds non matching rows from both, similar to a LEFT OUTER JOIN and a RIGHT OUTER JOIN. RIGHT OUTER JOIN ON - Adds to the INNER JOIN all the rows from the reserved right set with NULL for all the columns that come from the left set. LEFT OUTER JOIN ON - Adds to the INNER JOIN all the rows from the reserved left set with NULL for all the columns that come from the right set. INNER JOIN ON - Filters the cartesian product to only the rows where the join predicate evaluates to TRUE. Every JOIN starts as a Cartesian product. CROSS JOIN - Results in a Cartesian product of the two sets. ![]()
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