Answer posted by Scott on 2005-05-25 18:32:51: UNION - the values of the first query are returned with the values of the second query eliminating duplicates. MINUS - the values of the first query
Latest Answer: UNION: Take the common record once( No Duplicate)UNION ALL : Takes Duplicates alsoMinus: Result of first query - result of second queryexamleselect * from emp where rownum
Latest Answer: A query nested within another SQL statement is called a subquery. ...
Latest Answer: There are 5 types of joins available in sql server1) inner join2) outer join( left outer join,Right outer join)3) Full Join4) Cross Join5) Self Join1) inner Join : Two tables having the common column values go with inner join.Example:select * from emp ...
Answer posted by Scott on 2005-05-25 18:30:04: TRUNCATE is a DDL command and cannot be rolled back. All of the memory space is released back to the server. DELETE is a DML command and can be rolled
Latest Answer: DELETE is a logged operation on a per row basis. This means that the deletion of each row gets logged and physically deleted. You can DELETE any row that will not violate a constraint, while leaving the foreign key or any other contraint in place. ...
Latest Answer: Nextval must be used to generate a sequence number in the current user's session before currval can be referenced. ...
Latest Answer: A transaction is a UNIT of work. It contains a set of tasks to be completed as a SINGULAR UNIT of work. ...
Transaction is logical unit between two commits and commit and rollback.
Latest Answer: A Transaction is a logical unit of work that comprises one or more SQL statements executed by a single user. ...
Latest Answer: Till Oracle 7.0, only 12 triggers could be defined per table. In later versions there is no such limitation. ...
Latest Answer: CREATE TABLE duptest
( Id varchar(5),
nonid varchar(5));
INSERT INTO duptest VALUES('1','a');
INSERT INTO duptest VALUES('2','b');
SELECT * FROM duptest
DELETE FROM duptest WHERE rowid NOT IN (SELECT max(rowid) FROM duptest ...
Latest Answer: If a view is based upon a single table then DML operations can be performed on it, while if a view is based upon more than two tables then it is a complex view and DML operations can be performed using instead of triggers. ...
View page << Previous 1 2 3 4 [5] 6 7 8 9 10 Next >>
Go Top
