# AND and OR Conjunctive Operators

The PostgreSQL AND and OR operators are used to combine multiple conditions to narrow down selected data in a PostgreSQL statement. These two operators are called conjunctive operators.

These operators provide a means to make multiple comparisons with different operators in the same PostgreSQL statement.

## The AND Operator

The AND operator allows the existence of multiple conditions in a PostgreSQL statement’s WHERE clause. While using AND operator, complete condition will be assumed true when all the conditions are true. For example [condition1] AND [condition2] will be true only when both condition1 and condition2 are true.

### Syntax

The basic syntax of AND operator with WHERE clause is as follows −

```SELECT column1, column2, columnN
FROM table_name
WHERE [condition1] AND [condition2]...AND [conditionN];
```

You can combine N number of conditions using AND operator. For an action to be taken by the PostgreSQL statement, whether it be a transaction or query, all conditions separated by the AND must be TRUE.

### Example

Consider the table COMPANY having records as follows −

```testdb# select * from COMPANY;
id | name  | age | address   | salary
----+-------+-----+-----------+--------
1 | Paul  |  32 | California|  20000
2 | Allen |  25 | Texas     |  15000
3 | Teddy |  23 | Norway    |  20000
4 | Mark  |  25 | Rich-Mond |  65000
5 | David |  27 | Texas     |  85000
6 | Kim   |  22 | South-Hall|  45000
7 | James |  24 | Houston   |  10000
(7 rows)```

The following SELECT statement lists down all the records where AGE is greater than or equal to 25 AND salary is greater than or equal to 65000.00 −

`testdb=# SELECT * FROM COMPANY WHERE AGE >= 25 AND SALARY >= 65000;`

The above given PostgreSQL statement will produce the following result −

``` id | name  | age | address    | salary
----+-------+-----+------------+--------
4 | Mark  |  25 | Rich-Mond  |  65000
5 | David |  27 | Texas      |  85000
(2 rows)
```

## The OR Operator

The OR operator is also used to combine multiple conditions in a PostgreSQL statement’s WHERE clause. While using OR operator, complete condition will be assumed true when at least any of the conditions is true. For example [condition1] OR [condition2] will be true if either condition1 or condition2 is true.

### Syntax

The basic syntax of OR operator with WHERE clause is as follows −

```SELECT column1, column2, columnN
FROM table_name
WHERE [condition1] OR [condition2]...OR [conditionN]
```

You can combine N number of conditions using OR operator. For an action to be taken by the PostgreSQL statement, whether it be a transaction or query, only any ONE of the conditions separated by the OR must be TRUE.

### Example

Consider the COMPANY table, having the following records −

``` # select * from COMPANY;
id | name  | age | address   | salary
----+-------+-----+-----------+--------
1 | Paul  |  32 | California|  20000
2 | Allen |  25 | Texas     |  15000
3 | Teddy |  23 | Norway    |  20000
4 | Mark  |  25 | Rich-Mond |  65000
5 | David |  27 | Texas     |  85000
6 | Kim   |  22 | South-Hall|  45000
7 | James |  24 | Houston   |  10000
(7 rows)```

The following SELECT statement lists down all the records where AGE is greater than or equal to 25 OR salary is greater than or equal to 65000.00 −

`testdb=# SELECT * FROM COMPANY WHERE AGE >= 25 OR SALARY >= 65000;`

The above given PostgreSQL statement will produce the following result −

``` id | name  | age | address    | salary
----+-------+-----+------------+--------
1 | Paul  |  32 | California |  20000
2 | Allen |  25 | Texas      |  15000
4 | Mark  |  25 | Rich-Mond  |  65000
5 | David |  27 | Texas      |  85000
(4 rows)```

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