The DELETE statement is used to delete a row of data from a table. The syntax is: DELETE FROM table_name WHERE condition; the steps include: establishing a connection, writing a statement, executing a statement, confirming changes; Notes: permanently deleting data, restriction conditions, and only applicable to tables.
How to use SQL to delete a row of data in a table
In SQL, you can use the DELETE
statement to delete a row of data in a table. The syntax of this statement is as follows:
<code class="sql">DELETE FROM table_name WHERE condition;</code>
in:
-
table_name
is the table name to delete the data. -
condition
is the condition for the row to be deleted.
For example, to delete a row with id
5 from a table named customers
, you can use the following statement:
<code class="sql">DELETE FROM customers WHERE id = 5;</code>
Steps to execute a DELETE
statement:
- Establish a database connection: Use SQL client or programming language to establish a connection to the database.
- Write
DELETE
statement: WriteDELETE
statement based on the conditions of the row to be deleted. - Execution statement: Execute
DELETE
statements using SQL client or programming language. - Confirm changes: Check the data in the table to confirm that the target row has been successfully deleted.
Notes:
- The
DELETE
statement will permanently delete the data. Before deleting the data, make sure it has been backed up. - If
condition
does not specify any rows, it will delete all rows from the table. - You can use the
LIMIT
clause to limit the number of rows to be deleted. - The
DELETE
statement applies only to tables. To delete a view or other database object, you need to use a different statement.
The above is the detailed content of How to delete a row of data in a table in SQL. For more information, please follow other related articles on the PHP Chinese website!

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