Sqlserver Interview questions


Total available count: 45
Subject - Databases
Subsubject - Sqlserver

What are the properties and different Types of Sub-Queries?

Properties of Sub-Query:-
1. A sub-query must be enclosed in the parenthesis
2. A sub-query must be put in the right hand of the comparison operator
3. A sub-query cannot contain an ORDER-BY clause
4. A query can contain more than one sub-query
 
Types of Sub-Query:-
1. Single-row sub-query:-  Single-row sub-query, where the subquery returns only one row
2. Multiple-row sub-query:-  Multiple-row sub-query, where the subquery returns multiple rows
3. Multiple column sub-query:-  Multiple column sub-query, where the sub-query returns multiple columns



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