How to write the delete statement in oracle

Oracle’s DELETE statement can delete data from the database and follows the following syntax: DELETE FROM table name WHERE condition. The conditional clause specifies the rows to delete, using comparison and logical operators based on column values. Examples include deleting rows with a specific ID, rows with a specific last name, or rows that meet multiple criteria. It should be noted that if there is no WHERE clause, the entire table will be deleted; the deletion operation is irreversible, and it is recommended to back up the data before execution.

DELETE Statement in Oracle

The DELETE statement is used to delete data from an Oracle database. Its syntax is as follows:

DELETE FROM table_name
WHERE condition;

where clause:

The WHERE clause is used to specify which rows are to be deleted. Conditions can be based on the value of any column and can use comparison operators (=, >, <, etc.) and logical operators (AND, OR, NOT).

Example 1: Delete rows with specific ID

DELETE FROM customers
WHERE customer_id = 10;

Example 2: Delete all customers with specific last name

DELETE FROM customers
WHERE last_name = 'Smith';

Example 3: Delete rows with multiple conditions

DELETE FROM orders
WHERE order_date > '2023-01-01' AND order_amount < 100;

Other notes:

• If you do not use the WHERE clause, then All rows in the table will be deleted.
• You can use subqueries or join operations to specify more complex deletion conditions.
• Deleted data cannot be recovered. Always back up your data before executing a DELETE statement.
• You can use the DELETE ... RETURNING clause to return information about deleted rows.

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