In SQL, rows are deleted through the DELETE statement. The syntax is DELETE FROM table_name WHERE condition. In the parameters, table_name refers to the target table, and condition is an optional condition, specifying the rows to be deleted. If omitted, all rows will be deleted. For example: delete the row named "John" DELETE FROM customers WHERE name = 'John'; delete the amount greater than $100 row DELETE FROM orders WHERE amount > 100.
Statements to delete rows in SQL
How to delete rows
## The #DELETE statement is used to delete rows from a table.Syntax
DELETE FROM table_name WHERE condition;
Parameters
- table_name: The table to delete rows from name.
- condition: Optional condition that specifies which rows to delete. If you do not specify a condition, all rows in the table will be deleted.
Example
Delete all rows with the name "John" in thecustomers table:
DELETE FROM customers WHERE name = 'John';Delete
orders All rows in the table with amounts greater than $100:
DELETE FROM orders WHERE amount > 100;
Note
- Once deleted, the data will be permanently lost, so please Back up your data before executing the DELETE statement.
- If you do not specify a condition, all rows in the table will be deleted, including rows with foreign key relationships.
- To improve performance, consider using an index to speed up finding and deleting specified rows.
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