SQL - SPLessons

Chapter 1

SQL Tutorials

SQL Tutorials

SQL stands for Structured Query Language. The dialect initially created by IBM at mid 1970 and is utilized for dealing with the database. It is a non-procedural dialect. Client can compose SQL script to execute and SQL compiler consequently produces a method to get to database and convey the fancied output. SQL is a database coding, planned for the recuperation and organisation of data in social database.

Taking after outline clarifies how SQL getting to database to recover wanted information.

SQL – Is a procedural language.
Database – Is a collection of logical related data.

The below example describes the sample example of sql query.

Select * from employee;

It will display all the employees table values in the table.

SQL Languages

SQL is used for controlling all the functions provided by the DBMS like

  • Data Definition: SQL permits a client to characterize the structure of information to store and relate between them.
  • Data Retrieval: SQL helps a client or an operation to recover information from database.
  • Data Manipulation: SQL permit client or an operation to overhaul the current information, include some new information and erase existing information.
  • Access Control: SQL can likewise be utilized to confine a client or an application to get to some delicate information by setting up authorization level.

SQL process

SQL databases are very quick and user friendly database. SQL is an ANSI (American National Standards Institute) standard but there are many different versions of the SQL language.

  • SQL is published under an open-source license agreement.
  • SQL handles more expensive and powerful database packages.
  • SQL deals with C, C++, PHP, Java and so on and other working frameworks.
  • SQL works quick and handle even with tremendous information sets.
  • SQL is neighborly to PHP, the most section on dialect for web improvement.
  • SQL advances gigantic databases, upto 50 million columns and significantly more in the table. The default size point of confinement of a table is 4GB, however can be stretched out to a hypothetical cutoff of 8 million terabytes (TB).
  • SQL is imprint. In general source, GPL permits developers to change the SQL programming to suit their own particular informational system.

Summary

  • SQL – Stands for Structured Query Language.
  • Purpose of SQL Tutorials – Used for managing the database.
  • DDL – Stands for data definition language, and which is used to define data in database server.
  • DML – Stands for data manipulation language, and which is used to manipulate the data in database server.
  • Access control – Restrict the user to access confidential data.