Answer Posted / k
UNION provides only distinct values as output whereas UNION
ALL provides all values.
So UNION ALL seems to be faster than UNION.
Is This Answer Correct ? | 25 Yes | 1 No |
Post New Answer View All Answers
How would you best determine why your MVIEW couldnt FAST REFRESH?
How to define a procedure inside another procedure?
What is meant by an index?
What is the best way to do multi-row insert in oracle?
What is an oracle transaction?
How to use attributes of the implicit cursor in oracle?
how to join query for one source type is oracle another source type is sql server ?
In Oracle Clinical 4.5.0, can the VIEW_TEMPLATE_ID column in DATA_EXTRACT_VIEWS table contain NULL value?
What is a tns service name?
How to grant create session privilege to a user in oracle?
What are the differences between date and timestamp in oracle?
How to define an oracle cursor variable?
Describe varray?
What do you mean by merge in oracle and how can you merge two tables?
How do I reset a sequence in oracle?