Group by clauses-data manipulation language, Database Management System

Assignment Help:

Group By clauses

 • It is used to group database tuples on the basis of definite common attribute value like as employees of a department.

  • WHERE clause still can be used, if required.

Example: Search department number and Number of Employees working in that department.

 SELECT DEPTNO, COUNT(EMPNO) FROM EMP

GROUP BY DEPTNO;

Please note that as using group by and aggregate functions the only attributes that can be put in select clause are the aggregated functions and the attributes that have been used for grouping the information. For instance, in the example 20, we cannot put ENAME attribute in the SELECT clause as it will not have a distinct value for the group. Please note the group here is formed on DEPTNO.

 


Related Discussions:- Group by clauses-data manipulation language

Explain nonclustered indexes, What is the difference between SQL Server 200...

What is the difference between SQL Server 2000 clustered and nonclustered indexes? With a clustered index, the data are kept in the bottom level of the index and in the similar

What is transaction, What is transaction? Transaction is a unit of prog...

What is transaction? Transaction is a unit of program implementation that accesses and possibly updated several data items.

Sparse and dense indexes, Sparse and Dense Indexes These indexes in pri...

Sparse and Dense Indexes These indexes in principle are the similar as that of indexes used at the back of the book. The key facts of the indexes are: They are arranged

Nested query, what is correlation in nested query

what is correlation in nested query

Create a table for database transformation , Step 1 . Using Oracle, create ...

Step 1 . Using Oracle, create the tables identified in the preferred solution for Assignment 2. Technicians (ZipCode, TechnicianID, FirstName, LastName, Street, City, State, Home

Write the syntax of creating an index, Write the syntax of creating an INDE...

Write the syntax of creating an INDEX ? Syntax of Creating an Index: CREATE [BITMAP] [UNIQUE] INDEX ON ( [, ] . . .);

What are the factors into account when choosing a raid level, What are the ...

What are the factors to be taken into account when choosing a RAID level? A) Monetary cost of extra disk storage requirements. B) Performance requirements in terms of number

Fragmentation, let us consider a table having 2200 records and the fixed si...

let us consider a table having 2200 records and the fixed size of the table to be considered as 25.then how many numbers of table is requredto perform horizontal fragmentation

Datawarehouse, 1) Define a job scheduling strategy that will meet business ...

1) Define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pict

Using sql create a view rs for the relations r and s, Using SQL create a vi...

Using SQL create a view RS for the relations R and S. The view consists of the columns A and D renamed as X and Y in that order. Insert a tuple into it. Show the contents of t

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd