Can we rewrite subqueries into simple select statements or
with joins? Example?
Answers were Sorted based on User's Feedback
Answer / divya kalra
Subqueries can often be re-written to use a standard outer
join, resulting in faster performance. As we may know, an
outer join uses the plus sign (+) operator to tell the
database to return all non-matching rows with NULL values.
Hence we combine the outer join with a NULL test in the
WHERE clause to reproduce the result set without using a
sub-query.
| Is This Answer Correct ? | 4 Yes | 1 No |
Answer / syed sajjad
Yes we can write using Common Table Expression (CTE). A Common Table Expression (CTE) is an expression that can be thought of as a temporary result set which is defined within the execution of a single SQL statement. A CTE is similar to a derived table in that it is not stored as an object and lasts only for the duration of the query.
| Is This Answer Correct ? | 1 Yes | 0 No |
what is Data Transformation Services (DTS) ?can u explain me in detail?
What is bcp? When does it used?
Explain isolation levels that sql server supports?
explain different types of jions with examples briefly?
When a primary key constraint is included in a table, what other constraints does this imply?
What are the two authentication modes in sql server?
What is statement level trigger?
How do triggers work?
Does an index slow down updates on indexed columns?
code to create procedure for taking databse backup in sql server or i have the query for it but what it's query returns means i want to show on my jsp that the databse backup has been taken on the basis of that return value.does it returns 0 or 1.wat is the code for that
What does it mean to be in union?
How can I know what query is executing by by a particural user? (using sp id or any othe way.)
Oracle (3259)
SQL Server (4518)
MS Access (429)
MySQL (1402)
Postgre (483)
Sybase (267)
DB Architecture (141)
DB Administration (291)
DB Development (113)
SQL PLSQL (3330)
MongoDB (502)
IBM Informix (50)
Neo4j (82)
InfluxDB (0)
Apache CouchDB (44)
Firebird (5)
Database Management (1411)
Databases AllOther (288)