Showing posts with label SQL SELECT DISTINCT. Show all posts
Showing posts with label SQL SELECT DISTINCT. Show all posts

Monday, February 9, 2015

SQL SELECT DISTINCT


SQL SELECT DISTINCT


The SQL DISTINCT command is used with SELECT key word to retrieve only distinct or unique data.
In a table, there may be a chance to exist a duplicate value and sometimes we want to retrieve only unique values. In such scenarios, SQL SELECT DISTINCT statement is used.

Note: SQL SELECT UNIQUE and SQL SELECT DISTINCT statements are same.

Let's see the syntax of select distinct statement.
  1. SELECT DISTINCT column_name ,column_name  
  2. FROM  table_name;  
Let's try to understand it by the table given below:
Student_NameGenderMobile_NumberHOME_TOWN
Rahul OjhaMale7503896532Lucknow
Disha RaiFemale9270568893Varanasi
Sonoo JaiswalMale9990449935Lucknow
Here is a table of students from where we want to retrieve distinct information For example: distinct home-town.
  1. SELECT DISTINCT home_town  
  2. FROM students  
Now, it will return two rows.
HOME_TOWN
Lucknow
Varanasi