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Statement to delete rows in sql

May 07, 2024 am 06:12 AM

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.

Statement to delete rows in sql

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;
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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 the

customers table:

DELETE FROM customers
WHERE name = 'John';
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Delete

orders All rows in the table with amounts greater than $100:

DELETE FROM orders
WHERE amount > 100;
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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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