- do you require a combination of both column to be as primary key? then you can drop the existing primary key and create a new one with combination of both column:
- drop prmarykey
ALTER TABLE tablename
Truncate is a DDL Command where as Delete is a DML Command.
Both will delete data from table, but what is the difference between these below statements
truncate table <table_name> ??
delete from <table_name> ??
The first command cannot be …
Cursors in Oracle:
A cursor is used to process individual rows returned by database system for a query.
In oracle every SQL statement executed by the oracle server has a private area. This area contains information about the SQL statement and the…
Using examples as well as descriptions, step through each of the common simple join types, explaining differences in syntax, differences in expected outputs and showing how the queries run along with the actual outputs based upon a simple set of dem…