Questions

SQL statements are broadly classified into three. They are

1. DDL – Data Definition Language

DDL is used to define the structure that holds the data. For example, Create, Alter, Drop and Truncate table.

2. DML – Data Manipulation Language

DML is used for manipulation of the data itself. Typical operations are Insert, Delete, Update and retrieving the data from the table. The Select statement is considered as a limited version of the DML, since it can't change the data in the database. But it can perform operations on data retrieved from the DBMS, before the results are returned to the calling function.

3. DCL – Data Control Language

DCL is used to control the visibility of data like granting database access and set privileges to create tables, etc. Example - Grant, Revoke access permission to the user to access data in the database.

IRQ-0 is the system timer commonly use in all computers. In a computer, IRQ is an interrupt request which acts as a hardware signal sent to the processor that temporarily stops a running program and allows a special program, an interrupt handler, to run instead.

Sound waves cannot travel through a Vacuum.

A vacuum is an area without any air, like space. So sound cannot travel through space because there is no matter for the vibrations to work in.

Mooring buoy are white with a blue horizontal band. They usually are placed in marinas and other areas where boats are allowed to anchor. These are the only buoys you may tie up to legally.

Nigeria, an African country on the Gulf of Guinea. 

Nigeria has a Federal Republic and Presidential system of Government.

Many toxic gases along with water vapour are emitted in vocanic eruptions. All such toxic gases include hydrochloric acid, sulfur dioxide, carbon dioxide, hydrogen sulfide and carbon monoxide. Methane is not produced in the volcanic eruptions.