What is SQL Joins?
—SQL Joins are used to fetch/retrieve data from two or
more data tables, based on a join condition.
SQL JOIN is performed whenever two or more tables are
joined in a SQL statement.
Types Of Joins
• SQL Server INNER JOIN (or sometimes called simple join) SQL Server LEFT OUTER JOIN (or sometimes called LEFT JOIN) • SQL Server RIGHT OUTER JOIN (or sometimes called RIGHT JOIN) • SQL Server FULL OUTER JOIN (or sometimes called FULL JOIN) CROSS JOIN - Cross join is a cartesian join means cartesian product of both the tables. This join does not need any condition to join two tables. This join returns records/rows that are multiplication of record number from both the tables means each row on left table will related to each row of right table. SELF JOIN -- SELF JOIN is not a type of SQL Join It is the most common type of join. SQL Server INNER JOINS return all rows from multiple tables where the join Syntax SELECT columns FROM table1 INNER JOIN table2 ON table1.column = table2.column;
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