What is the difference between UNION and UNIONALL?
Answer Posted / suresh
UNION statement effectively does a SELECT DISTINCT on the
results set. If you know that all the records returned are
unique from your union, use UNION ALL instead, it gives
faster results.
Is This Answer Correct ? | 13 Yes | 1 No |
Post New Answer View All Answers
What are entities and relationships?
What is a data collection table?
What is not null constraint?
Explain the types of indexes.
How to connect php with different port numbers?
i have made a project i vb.net n created a .exe of it after installing it in to any pc, the database (sql express) is not geting accesed i.e the aplication cuts the link of the database, so plz help in this matter.
What is indexing in sql server with example?
How do I clean up sql server transaction log?
Explain query editor regions
What is difference between unique and primary key?
How to how to convert numeric expression data types using the convert() function??
What is data source object?
how would you improve etl (extract, transform, load) throughput?
What is report server project?
Disadvantages of the indexes?