DAY-1: THE SQL

What is SQL?

SQL stands for Structured Query Language. SQL is used to communicate with a database. According to American National Standards Institute, it is the standard language for relational database management systems.

SQL statements are used to perform tasks such as update data on a database, or retrieve data from a database. Some common relational database management systems that use SQL are: Oracle, Sybase, Microsoft SQL Server, Access, etc. 

However, the standard SQL commands can be used to accomplish almost everything that one needs to do with a database. This tutorial will provide you with the instruction on the basics of each of these commands as well as allow you to put them to practice using the SQL Interpreter.

SQL expression consists of three clauses: select, from, and where. A sample SQL statement that makes this query is:

SELECT * FROM STUDENT 

The most commonly used statement in SQL is the SELECT statement, which retrieves data from the database and returns the data to the user. The STUDENT table example illustrates a typical example of a SELECT statement situation. In addition to the SELECT statement, SQL provides statements for creating new databases, tables, fields, and indexes, as well as statements for inserting and deleting records. The  from clause by itself defines a Cartesian Product of the relations in the clause. Here STUDENT is the name of the relation (Entity Set/Table).

Now, Analyze the STUDENT table and SELECT statement with fundamental knowledge of Database, Table, Field from HERE.

No comments:

Post a Comment

Popular Posts