The PostgreSQL UPDATE Query is utilized to adjust the current records in a table. You can utilize WHERE provision with UPDATE question to refresh the chose lines. Something else, all the lines would be refreshed.
Syntax
The essential punctuation of UPDATE question with WHERE proviso is as per the following −
UPDATE table_name
SET column1 = value1, column2 = value2...., columnN = valueN
WHERE [condition];
You can consolidate N number of conditions utilizing AND OR administrators.
Example
Think about 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)
Coming up next is a model, which would refresh ADDRESS for a client, whose ID is 6 −
testdb=# UPDATE COMPANY SET SALARY = 15000 WHERE ID = 3;
Presently, COMPANY table would have the accompanying records −
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
6 | Kim | 22 | South-Hall | 45000
7 | James | 24 | Houston | 10000
3 | Teddy | 23 | Norway | 15000
(7 rows)
In the event that you need to change all ADDRESS and SALARY section esteems in COMPANY table, you don't have to utilize WHERE condition and UPDATE question would be as per the following −
testdb=# UPDATE COMPANY SET ADDRESS = 'Texas', SALARY=20000;
Presently, COMPANY table will have the accompanying records −
id | name | age | address | salary
----+-------+-----+---------+--------
1 | Paul | 32 | Texas | 20000
2 | Allen | 25 | Texas | 20000
4 | Mark | 25 | Texas | 20000
5 | David | 27 | Texas | 20000
6 | Kim | 22 | Texas | 20000
7 | James | 24 | Texas | 20000
3 | Teddy | 23 | Texas | 20000
(7 rows)