How to write a SQL delete statement

The SQL delete statement is a DELETE FROM, which is used to delete rows from the specified table. The syntax is: DELETE FROM table_name WHERE condition. condition is an optional condition that specifies the row to be deleted. If no conditions are specified, all rows are deleted. Example: DELETE FROM customers WHERE customer_id = 2; Delete line with customer_id of 2.

SQL Delete Statement

The statement used in SQL to delete data is DELETE FROM . It works in the form of deleting specific rows in a specified table.

Basic syntax:

 <code class="sql">DELETE FROM table_name WHERE condition;</code>

in:

• table_name is the table name from which rows are to be deleted.
• condition is an optional condition that specifies which rows to delete. If no criteria are specified, all rows in the table will be deleted.

usage:

Delete all rows in the table:

 <code class="sql">DELETE FROM table_name;</code>

Delete rows that meet certain criteria:

 <code class="sql">DELETE FROM table_name WHERE column_name = 'value';</code>

Example:

Suppose there is the following table customers :

 <code>| customer_id | customer_name | |-------------|---------------| | 1 | John Doe | | 2 | Jane Smith | | 3 | David Wilson |</code>

Delete the line with the specified customer_id:

 <code class="sql">DELETE FROM customers WHERE customer_id = 2;</code>

Delete all lines that start with "J" by customer_name:

 <code class="sql">DELETE FROM customers WHERE customer_name LIKE 'J%';</code>

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