Delete Query - SQL
Delete Query - SQL is used to delete the existing records from a table.
You can use WHERE clause with DELETE query to delete selected rows, otherwise all the records would be deleted.
The basic syntax of DELETE query with WHERE clause is as follows:
You can combine N number of conditions using AND or OR operators.
Consider the CUSTOMERS table having the following records:
Following is an example, which would DELETE a customer, whose ID is 6:
Now, CUSTOMERS table would have the following records:
If you want to DELETE all the records from CUSTOMERS table, you do not need to use WHERE clause and DELETE query would be as follows:
Now, CUSTOMERS table would not have any record.
You can use WHERE clause with DELETE query to delete selected rows, otherwise all the records would be deleted.
Syntax:
The basic syntax of DELETE query with WHERE clause is as follows:
DELETE FROM table_name
WHERE [condition];
You can combine N number of conditions using AND or OR operators.
Example:
Consider the CUSTOMERS table having the following records:
+----+----------+-----+-----------+----------+
| ID | NAME | AGE | ADDRESS | SALARY |
+----+----------+-----+-----------+----------+
| 1 | Ramesh | 32 | Ahmedabad | 2000.00 |
| 2 | Khilan | 25 | Delhi | 1500.00 |
| 3 | kaushik | 23 | Kota | 2000.00 |
| 4 | Chaitali | 25 | Mumbai | 6500.00 |
| 5 | Hardik | 27 | Bhopal | 8500.00 |
| 6 | Komal | 22 | MP | 4500.00 |
| 7 | Muffy | 24 | Indore | 10000.00 |
+----+----------+-----+-----------+----------+
Following is an example, which would DELETE a customer, whose ID is 6:
SQL> DELETE FROM CUSTOMERS
WHERE ID = 6;
Now, CUSTOMERS table would have the following records:
+----+----------+-----+-----------+----------+
| ID | NAME | AGE | ADDRESS | SALARY |
+----+----------+-----+-----------+----------+
| 1 | Ramesh | 32 | Ahmedabad | 2000.00 |
| 2 | Khilan | 25 | Delhi | 1500.00 |
| 3 | kaushik | 23 | Kota | 2000.00 |
| 4 | Chaitali | 25 | Mumbai | 6500.00 |
| 5 | Hardik | 27 | Bhopal | 8500.00 |
| 7 | Muffy | 24 | Indore | 10000.00 |
+----+----------+-----+-----------+----------+
If you want to DELETE all the records from CUSTOMERS table, you do not need to use WHERE clause and DELETE query would be as follows:
SQL> DELETE FROM CUSTOMERS;
Now, CUSTOMERS table would not have any record.
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