SQL DELETE Statement
The SQL DELETE statement is used to remove rows from a table. The basic syntax of the DELETE statement is as follows:
DELETE FROM
table_name
WHERE condition;
Here, table_name is the name of the table that you want to delete rows from. The WHERE clause is used to specify the conditions that must be met for a row to be deleted. If the WHERE clause is not specified, all rows in the table will be deleted.
For example, suppose you have a table called employees with columns id, first_name, last_name, email, and hire_date. If you want to delete the row for an employee with ID 1, you would use the following SQL statement:
DELETE FROM
employees
WHERE id = 1;
This statement will delete the row for the employee with ID 1.
You can also delete multiple rows that meet a specific condition. For example, if you want to delete all employees who were hired before 2022, you would use the following SQL statement:
DELETE FROM
employees
WHERE hire_date < '2022-01-01';
This statement will delete all rows from the employees table where the hire_date is before January 1, 2022.
It is important to use
caution when deleting data in a database, as deletions can potentially
affect many rows or even the entire table. Always double-check your WHERE clause to make sure that you are deleting only the rows that you intend to delete. Additionally, it is a good practice to make a backup of the table before deleting any rows, so that you can easily restore the data if necessary.
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