SQL Select with Order By, Insert, Update and Delete Command

In this article we will look at various SQL commands like Insert, Update, Delete, Select, Order By etc. which is used to manage and manipulate data with the help of examples.

SQL Insert

Insert into employee values (1,'Joy',28)

Insert into employee(EMPLOYEE_ID, EMPLOYEE_NAME) values (1,'Joy')

SQL Update

SQL Update is used to update data in a row or set of rows specified in the filter condition. The basic format of an SQL UPDATE statement is, "Update" command followed by table to be updated and SET command followed by column names and their new values followed by filter condition that determines which rows should be updated.

Update employee set age = 35 where EMPLOYEE_NAME = 'Joy'

SQL Delete

SQL Delete is used to delete a row or set of rows specified in the filter condition. The basic format of an SQL DELETE statement is, "DELETE From" command followed by table name followed by filter condition that determines which rows should be updated. To update a row in employee table, SQL query will be as shown below.

Delete from employee where EMPLOYEE_NAME = 'Joy'

SQL Select Statement

SQL “select” statement is used to retrieve data from table. For example, to retrieve data from the table given below, following SQL select statements are used

Table Name : Employee

To retrieve complete data from table use SQL select Query

Select * from Employee;

Result is as given below

To retrieve a column from table, use following SQL select Query

Select Employee_Name from Employee

The above query will produce following result.

Select Employee_Name,Age from Employee

The result of the above query is given below.

SQL Alias Name

SQL Alias name is used to give a alias name to a column or a calculated field. For example, if item wise total need to be obtained from Sales table given below

Table Name : Sales

Select items, quantity * price Total from sales

Result of the above query is as shown below.

Here result of quantity * price is returned as “Total” which is the alias name.

SQL Order By

SQL “Order by” clause is used to sort data retrieved from a table. For example, to retrieve data from the table given below sorted by employee name, following SQL select statements are used

Select * from Employee order by Employee_Name

To retrieve data from the table sorted by multiple table columns, following SQL select statements are used.

Select * from Employee order by Employee_id, age

SQL Sort Direction

To retrieve data from employee table, sorted by name descending, following SQL statement is used.

Select * from Employee order by employee_name desc

• < Prev
• Next >