Create, Drop, Insert, Update, Delete and Select – The Basic SQL

This topic for those who are very beginner of SQL. Here I will show some basic SQL by Microsoft SQL Server.

1. Create a table: Here I created a table name hrm_employee. Here emp_gid is int type, primary key and identity. Identity means its value will increment automatically by the sql server. You don’t need to insert it’s value.

--Create Table : hrm_employee---
CREATE TABLE hrm_employee
(
  emp_gid INT PRIMARY KEY IDENTITY,
  emp_fullnm VARCHAR(100),
  emp_nicknm VARCHAR(50),
  emp_designation VARCHAR(100)
)

2. Insert data in hrm_employee table: In this occasion, I have inserted 3 data i.e 3 rows. If you see in closer look, you will see that I didn’t insert any value of emp_gid because it increments its value automatically because it is an identity column.

--Insert data ito table: hrm_employee----

-- Insert data i.e. row-1 ---
INSERT INTO hrm_employee
(
  emp_fullnm, 
  emp_nicknm, 
  emp_designation
)
VALUES
(
'Md. Mahedee Hasan', 
'Mahedee', 
'Senior Software Engineer'
)

-- Insert data i.e. row-2 ---
INSERT INTO hrm_employee
(
emp_fullnm
, emp_nicknm
, emp_designation
)
VALUES
(
'Md. Asrafuzzaman'
, 'Emon'
, 'Senior Software Engineer'
)

-- Insert data i.e. row-3 ---
INSERT INTO hrm_employee
(
emp_fullnm
, emp_nicknm
, emp_designation
)
VALUES
(
'Md. Khondakar Enamul Haque'
, 'Rony'
, 'Broadcast Engineer'
)

3. Infromation Retrive: Get all information of hrm_employee. Here I showed two ways to retrive data and I suggest to use second one. Second one is best practiced.

--Get all data from hrm_employee--
SELECT * FROM hrm_employee
--or
SELECT emp_gid, emp_fullnm, emp_nicknm, emp_designation FROM hrm_employee

4. Update hrm_employee: Is very easy to update a row or multiple rows against a condition. Lets look on the following query.

--update data from table: hrm_employee --
UPDATE hrm_employee
SET emp_fullnm = 'M.K. Enamul Haque'
, emp_designation = 'Senior Broadcast Engineer'
WHERE emp_gid = 3

5. Delete Information: If you want to delete information from hrm_employee against a condition follow the query.

---Delete data from table: hrm_employee---
DELETE FROM hrm_employee WHERE emp_gid = 3

6. Drop Table: Drop table means remove table for database. Use the query to drop hrm_employee table.

---Drop table i.e remove table from Database--
DROP TABLE hrm_employee