Quiz: SQL-Programming Test Questions

What is SQL?

Structured Query Language, or SQL (pronounced "sea-que-el"), is a query language. A database can be communicated using SQL. It is the accepted language for relational database management systems, claims ANSI (American National Standards Institute). To change data on a database or to obtain data from a database, SQL statements are employed. Oracle, Sybase, Microsoft SQL Server, Access, Ingres, and other popular relational database management systems are only a few examples.

Despite using SQL often, most database systems also contain proprietary extensions that are typically only utilized with that systems. The typical SQL commands, however, such as "Select," "Insert," "Update," "Delete," "Create," and "Drop," can be used to complete nearly any database-related tasks. 

Commonly Used SQL Commands

You need to be familiar with a few commonly used SQL commands for database operations. When utilizing databases, a programmer might create the following commands:

• CREATE DATABASE – to create a database
• CREATE TABLE – to create tables
• CREATE INDEX – creates an index (search key)
• DROP INDEX – deletes an index
• SELECT – to find/extract some data from a database
• UPDATE – make adjustments and edit data
• ALTER TABLE - modifies a table
• DELETE – to delete some data
• DROP TABLE – to remove tables and databases
• INSERT INTO – to insert new data into a database
• ALTER DATABASE – modifies a database.

These are the most widely used commands. These Sequel procedures are employed when writing queries—inquiries that let you work with data in databases. Put it another way, the database system interprets and executes the commands you enter when you use them.