Oracle Certification Questions

Alter database backup control file to trace

A .MOV file is a common multimedia container file format developed by Apple. It may contain multiple tracks that store different types of media data and is often used for saving movies and other video files.

A primary key is a special relational database table column or combination of columns designated to uniquely identify all table records. That is, A primary key is a column or set of columns in a table that uniquely identifies tuples (rows) in that table.

A primary key, also called a Primary Keyword.

Main Features Primary key are ::

It must contain a unique value for each row of data.

It cannot contain null values.

Executive plan can be defined as:

* SQL Server caches collected procedure or the plan of query execution and used thereafter by subsequent calls.

* An important feature in relation to performance enhancement.

* Data execution plan can be viewed textually or graphically.

XPath is an expressions to select a xml node in an XML document.

It allows the navigation on the XML document to the straight to the element where we need to reach and access the attributes.

A database that contains multiple tables related through common fields.

A common field is a field of data that is shared among all forms in a database. Without them, it would be difficult and/or time-consuming to create other forms.

The difference between Union and Union all is that Union all will not eliminate duplicate rows, instead it just pulls all rows from all tables fitting your query specifics and combines them into a table. A UNION statement effectively does a SELECT DISTINCT on the results set.

Data Control Language (DCL):-statements to take care of the security and authorization.

Examples:

1. GRANT


2. REVOKE