VB.NET Select statement in SQL query
This article primarily devoted to the basics of SQL query, that is SELECT Statement: This SELECT statement is used to fetch data from the table.
This article primarily devoted to the basics of SQL query, that is SELECT Statement:
This SELECT statement is used to fetch data from the table.
Syntax:
SELECT column_name(s) FROM table_name
Suppose we have a "Employee" table
LastName
|
FirstName
|
Address
|
City
|
Singh
|
Bhupendr
|
10, K. Marg
|
New Delhi
|
Das
|
Bhasker
|
34, mall road
|
Kanpur
|
Singh
|
Ajeet
|
15, karol bagh
|
New Delhi
|
For Select Few Columns:
SELECT LastName,FirstName FROM Employee
Query Result is:
LastName FirstName
Singh Bhupendr
Das Bhasker
Singh Ajeet
Select All Columns
To select all columns from the "Employee" table, use a * symbol instead of column names, like this:
SELECT * FROM Employee
LastName FirstName Address City
Singh Bhupendr 10, K. Marg New Delhi
Das Bhasker 34, mall road Kanpur
Singh Ajeet 15, karol bagh New Delhi
The SELECT DISTINCT Statement
The DISTINCT keyword is used to fetch only distinct (different) values no repetitive values from the table.
Syntax
SELECT DISTINCT column_name(s) FROM table_name
Suppose we have one more table: "Orders" table
Company
|
OrderNumber
|
MCN
|
3412
|
Microsoft
|
2312
|
MCN
|
4678
|
Wipro
|
6798
|
Without using the DISTINCT keyword
To select ALL values from the column named "Company" we use a SELECT statement like this:
SELECT Company FROM Orders
Company
MCN
Microsoft
MCN
Wipro
To select only DIFFERENT values from the column named "Company" we use a SELECT DISTINCT statement like this:
SELECT DISTINCT Company FROM Orders
Company
MCN
Microsoft
Wipro