What is Cursor?
Cursor is bassically a database object,which is manily used by applications to
manipulate data in a set on a Row by Row basis, Inastead of use the typical
SQL commands that operate on all the rows in the set at one time. In order to
workwith a cursor we need to perform some steps in theFollowing order :
> Declare cursor
> Open cursor
> Fetch row from the cursor
> Process fetched row
> Close cursor
> Deallocate cursor
What is a Linked Server?
Linked Servers is bassically a concept in SQL
Server, Its mainly use we can add the other SQL
Server to a Group and query both the SQL Server
dbs using T-SQL Statements. With a linked
server, We can also create very clean,easy to
follow, And SQL statements that allow remote data
to be retrieved, joined and combined with local
What is the mean of Nested Trigger?
A Trigger have a many authorities it can also perform to the INSERT,UPDATE and DELETE oprations or logic within itself, And whenever the trigger is fired the
reason is that data modification, It can also the reason is another data
modification, may be firing another trigger. A Trigger that contains data
modification logic within itself is called a nested trigger.
What are the properties of the Relational tables?
Relational tables have six properties which is there :
> In this table Values are atomic.
> In this table Column values are of the same kind.
> In this table Each row is unique.
> In this table The sequence of columns is insignificant.
> In this table The sequence of rows is insignificant.
> In this table Each column must have a unique name.Reply
What is the Foriegn Key?
Catalogue No. - Date - Times Played
Supose we have a table whihc name is Play history and its have a three colums Catalogue No and Date anf Times Play.These are three Colums in a 1 row.
In this situation the Catalogue No. number is a Primary Key in the CDs table but only part of the Composite Key in the Play History table as the date is required to form the whole key. An alternative could have been to create a new unique single-attribute Primary Key for the table. As we still need to know the catalogue number in order to work out how many times a DJ has played Britney, Christina or Pink. The catalogue number would become the Foreign Key in the Play History table,that is Foreign Key is a attribute or column in a table that refers to a Primary Key in another table.Reply
What do you mean by Candidate key?
Condidate key is bassically use for when we added a new attribute in the table, We could also use the combination of other attribute with this new attribute to identify the row, as together they form a Composite Key. Thus we have two potential or Candidate Keys.Reply
Define the Primary key?
The Primary Key is bassically a key that is frequently used to identify a specific row other keys also may exist and all the other values are dependent on that value to be meaningfully identified. A primary key is usually one attribute or column in a relation or table, But can be a combination of attributes.Reply
What is an Oracle view?
A view is a bassically logical table which makes a change complex query to easy term .We can even create a complex view by joining two tables.Reply
What is Oracle table?
The Collection of informations stored in the strutrued format which is in rows and columns formate that is called a table.Reply
Can a tablespace hold objects from different schemes?
Yes we can a template hold objects from different schemes.Reply