Joins are used in queries to explain how
different tables are related. Joins also let you select data from a table
depending upon data from another table.
Types of joins: INNER JOINs, OUTER JOINs, CROSS JOINs. OUTER JOINs are further classified as LEFT OUTER JOINS, RIGHT OUTER JOINS and FULL OUTER JOINS.
Inner Join shows only matched record from multiple tables.
Left Join shows all records from left table and matched records from right table.
Right Join shows all records from right table and matched records from left table.
Full outer Join shows all records from multiple tables. (Inner + Left + Right)
Types of joins: INNER JOINs, OUTER JOINs, CROSS JOINs. OUTER JOINs are further classified as LEFT OUTER JOINS, RIGHT OUTER JOINS and FULL OUTER JOINS.
Inner Join shows only matched record from multiple tables.
Left Join shows all records from left table and matched records from right table.
Right Join shows all records from right table and matched records from left table.
Full outer Join shows all records from multiple tables. (Inner + Left + Right)
No comments:
Post a Comment