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प्रश्न
Construct the following SQL statement in the student table-
SELECT statement using GROUP BY clause.
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उत्तर
GROUP BY clause
The GROUP BY clause is used with the SELECT statement to group the students on rows or columns having identical values or divide the table into groups. For example to know the number of male students or female students of a class, the GROUP BY clause may be used. It is mostly used in conjunction with aggregate functions to produce summary reports from the database.
The syntax for the GROUP BY clause is
SELECT <column-names> FROM <table-name> GROUP BY <column-name>HAVING condition];
To apply the above command on the student table :
SELECT Gender FROM Student GROUP BY Gender;
The following command will give the below-given result:
| Gender |
| M |
| F |
SELECT Gender, count(*) FROM Student GROUP BY Gender;
| Gender | count(*) |
| M | 5 |
| F | 3 |
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| EMP CODE | NAME | DESIG | PAY | ALLO WANCE |
| S1001 | Hariharan | Supervisor | 29000 | 12000 |
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| P1003 | Prasad | Operator | 12000 | 6500 |
| C1004 | Manjima | Clerk | 8000 | 4500 |
| M1005 | Ratheesh | Mechanic | 20000 | 7000 |
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