What is inner join and outer join in SQL with examples?
Here are the different types of the JOINs in SQL: (INNER) JOIN : Returns records that have matching values in both tables. … RIGHT (OUTER) JOIN : Returns all records from the right table, and the matched records from the left table. FULL (OUTER) JOIN : Returns all records when there is a match in either left or right …
What are the types of inner join?
Inner Join is further divided into three subtypes: 1) Theta join 2) Natural join 3) EQUI join.
When inner join is used?
Generally, we use INNER JOIN when we want to select only rows that match an ON condition. If no rows match the ON condition, then it will not return any results. This can be somewhat stricter than using a LEFT JOIN .
What is equi join?
An equi-join is a basic join with a WHERE clause that contains a condition specifying that the value in one column in the first table must be equal to the value of a corresponding column in the second table.
Which join is faster in SQL?
You may be interested to know which is faster – the LEFT JOIN or INNER JOIN. Well, in general INNER JOIN will be faster because it only returns the rows matched in all joined tables based on the joined column.
How use inner join condition?
To use the WHERE clause to perform the same join as you perform using the INNER JOIN syntax, enter both the join condition and the additional selection condition in the WHERE clause. The tables to be joined are listed in the FROM clause, separated by commas. This query returns the same output as the previous example.
What is faster Left join or inner join?
A LEFT JOIN is absolutely not faster than an INNER JOIN . In fact, it’s slower; by definition, an outer join ( LEFT JOIN or RIGHT JOIN ) has to do all the work of an INNER JOIN plus the extra work of null-extending the results.
What is join with example?
A natural join returns all rows by matching values in comman columns having same name and data types of columns and that column should be present in both tables. • Natural join eliminates duplicate columns present in JOIN table. Therefore comman column will be printed only once in resultant table.
How many types of joins are there?
ANSI-standard SQL specifies five types of JOIN : INNER , LEFT OUTER , RIGHT OUTER , FULL OUTER and CROSS .
What is right join?
Right joins are similar to left joins except they return all rows from the table in the RIGHT JOIN clause and only matching rows from the table in the FROM clause. RIGHT JOIN is rarely used because you can achieve the results of a RIGHT JOIN by simply switching the two joined table names in a LEFT JOIN .