Delete query in sqlite for child tables

I have 3 tables, like Employee, Department and开发者_如何学C Electronics tables.

Electronics table is child table for Department table and Department table is child table for Employee table.

I want to delete one record in Employee table where E_id=2 ( this is Primary key) this is Foreign key in Department table (E_id is Foreign key and Dept_id is Primary key) and Dept_id is Foreign Key in Electronics table.

First I want to delete related records in Electronics table then Department table and finally Employee table.

Please guide me how to do it.

---

You can read more about foreign key support in sqlite here: http://www.sqlite.org/foreignkeys.html

but you should be able to turn it on:

sqlite> PRAGMA foreign_keys = ON;

and then setup the database schema with the deletes cascading:

-- Database schema
CREATE TABLE Employee(
  E_id    INTEGER PRIMARY KEY, 
  name    TEXT
);
CREATE TABLE Department(
  Dept_id     INTEGER PRIMARY KEY,
  name   TEXT, 
  E_id INTEGER REFERENCES Employee(E_id) ON DELETE CASCADE
);
CREATE TABLE Electronics(
  Elec_id     INTEGER PRIMARY KEY,
  name   TEXT, 
  Dept_id INTEGER REFERENCES Department(Dept_id) ON DELETE CASCADE
);

With all this in place and the data in the tables:

DELETE FROM Employee WHERE E_id = 2;