top button
Flag Notify
    Connect to us
      Site Registration

Site Registration

What is sub-query? Explain properties of sub-query?

0 votes
496 views
What is sub-query? Explain properties of sub-query?
posted Nov 26, 2014 by Balu

Share this question
Facebook Share Button Twitter Share Button LinkedIn Share Button

1 Answer

0 votes

Sub-queries are often referred to as sub-selects, as they allow a SELECT statement to be executed arbitrarily within the body of another SQL statement. A sub-query is executed by enclosing it in a set of parentheses. Sub-queries are generally used to return a single row as an atomic value, though they may be used to compare values against multiple rows with the IN keyword.
A subquery is a SELECT statement that is nested within another T-SQL statement. A subquery SELECT statement if executed independently of the T-SQL statement, in which it is nested, will return a resultset. Meaning a subquery SELECT statement can standalone and is not depended on the statement in which it is nested. A subquery SELECT statement can return any number of values, and can be found in, the column list of a SELECT statement, a FROM, GROUP BY, HAVING, and/or ORDER BY clauses of a T-SQL statement. A Subquery can also be used as a parameter to a function call. Basically a subquery can be used anywhere an expression can be used.

answer Nov 26, 2014 by Manikandan J
Similar Questions
–1 vote

Table Name : Employee
Employee_id First_name Last_name Salary Joining_date Department
1 John Abraham 1000000 01-JAN-13 12.00.00 AM Banking
2 Michael Clarke 800000 01-JAN-13 12.00.00 AM Insurance
3 Roy Thomas 700000 01-FEB-13 12.00.00 AM Banking
4 Tom Jose 600000 01-FEB-13 12.00.00 AM Insurance
5 Jerry Pinto 650000 01-FEB-13 12.00.00 AM Insurance
6 Philip Mathew 750000 01-JAN-13 12.00.00 AM Services
7 TestName1 123 650000 01-JAN-13 12.00.00 AM Services
8 TestName2 Lname% 600000 01-FEB-13 12.00.00 AM Insurance
Table Name : Incentives
Employee_ref_id Incentive_date Incentive_amount
1 01-FEB-13 5000
2 01-FEB-13 3000
3 01-FEB-13 4000
1 01-JAN-13 4500
2 01-JAN-13 3500

+1 vote

Explain about the properties of the Relational tables

...