SQL DELETE FROM TABLE



SQL DELETE FROM Statement

The SQL DELETE FROM statement is used to remove rows from an existing table. You can specify which rows to delete by using the WHERE clause. If no condition is specified, all rows in the table will be deleted.


Syntax

DELETE FROM table_name
WHERE condition;
  • DELETE FROM: This is the SQL keyword used to delete rows from a table.
  • table_name: This specifies the name of the table from which you want to delete rows.
  • condition: This specifies the condition that determines which rows to delete.

Example

Let's go through a complete example that includes creating a database, creating a table, inserting data into the table, and then deleting specific rows from the table.

Step 1: Creating a Database

This step involves creating a new database where the table will be stored.

CREATE DATABASE example_db;

In this example, we create a database named example_db.

Step 2: Creating a Table

In this step, we create a table named employees within the previously created database.

USE example_db;

CREATE TABLE employees (
    id INT AUTO_INCREMENT PRIMARY KEY,
    first_name VARCHAR(50) NOT NULL,
    last_name VARCHAR(50) NOT NULL,
    email VARCHAR(100),
    hire_date DATE
);

Here, we define the employees table with columns for id, first_name, last_name, email, and hire_date. The id column is set as the primary key and will auto-increment.

Step 3: Inserting Data into the Table

This step involves inserting some sample data into the employees table.

INSERT INTO employees (first_name, last_name, email, hire_date) VALUES ('John', 'Doe', 'john.doe@example.com', '2023-01-01');
INSERT INTO employees (first_name, last_name, email, hire_date) VALUES ('Jane', 'Smith', 'jane.smith@example.com', '2023-02-01');

Here, we insert two rows of data into the employees table.

Step 4: Deleting Rows from the Table

This step involves deleting specific rows from the employees table based on a condition.

DELETE FROM employees
WHERE last_name = 'Doe';

This command will delete all rows from the employees table where the last_name is 'Doe'.

If you want to delete all rows from the table, you can use the following command:

DELETE FROM employees;

This command will delete all rows from the employees table, leaving it empty but still retaining its structure.