SQL Joins

SQL JOINS:-  JOIN means to combine something. In case of SQL join clause is used to combine rows from two or more table, based on a related column between them.

IMPORTANCE OF JOIN:-
  • If you want to combine two or more table the SQL JOIN is used.
  • If you want to access more than one table through a SELECT statement.
  • The joining of two or more tables is based on common filed between them.

TYPES OF JOIN:-
  • INNER JOIN:-INNER JOIN returns records that have matching values in both the table.
  • LEFT(OUTER) JOIN:- This join returns all records from the left table , and the matched record from the right table.
  • RIGHT(OUTER) JOIN:- This join returns all records from the right table, and the matched records from the left table.
  • FULL(OUTER) JOIN:-This join returns all records when there is s match in either left or the right table.



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