To display unique/distinct records
Command: Distinct clause
Helps us to eliminate duplicate records while displaying the details
Roll Name age
101 Aaa 10
102 Bbb 12
101 Aaa 10
103 Aaa 14
104 Ccc 15
101 Aaa 10
105 Eee 15
Example:1
Select * from std;
All the records will be displayed
Example:2
Select distinct * from std;
Roll Name age
101 Aaa 10
102 Bbb 12
103 Aaa 14
104 Ccc 15
105 Eee 15
Example:3
Select distinct roll from std;
101
102
103
104
105
Example:4
Select distinct name from std;
Aaa
Bbb
Ccc
Eee
To display the record in proper order
Command: Order by clause
Helps us to display the records in a particular order
By default, the records are displayed in ascending order. In order to display the records in descending order, we have to use “desc” clause.
Select * from std order by roll;
Select * from std order by name;
Select * from std order by name, roll;
If required two or more columns can be used along with order by clause. The records are firstly arranged according to first column. And the records which have same value of the first column are arranged according to the second column and so on.
Using desc clause
Select * from std order by roll desc;
Select * from std order by name desc;
