Structured Query Language (SQL) - GeeksforGeeks

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• SQL is case insensitive

• Data Definition Language: It is used to define the structure of the database. e.g; CREATE TABLE, ADD COLUMN, DROP COLUMN and so on

• Data Manipulation Language: It is used to manipulate data in the relations. e.g.; INSERT, DELETE, UPDATE and so on

• Data Query Language: It is used to extract the data from the relations. e.g.; SELECT

• Tuple:Each row in the relation is known as tuple. The above relation contains 4 tuples, one of which is shown as: 1 RAM DELHI 9455123451 18

• Attribute:Attributes are the properties that define a relation. e.g.; ROLL_NO, NAME etc.

• standard Database language

• create, maintain, and retrieve the relational database.

• case insensitive. But it is a recommended practice to use keywords (like SELECT, UPDATE, CREATE, etc.) in capital letters

• ser-defined things (like table name, column name, etc.) in small letters.

• data is stored as well as retrieved in the form of relations (

• Tuple:Each row in the relation is known as tuple. The above relation contains 4 tuples, one of which is shown as:

• The number of attributes in the relation is known as degree of the relation. The STUDENT relation defined above has degree 5.

• Degree:

• Cardinality:The number of tuples in a relation is known as cardinality. The STUDENTrelation defined above has cardinality 4.

• Column:Column represents the set of values for a particular attribute. The column ROLL_NO is extracted from relation STUDENT.

• Data Definition Language:It is used to define the structure of the database. e.g; CREATE TABLE, ADD COLUMN, DROP COLUMN and so on.

• Data Manipulation Language:It is used to manipulate data in the relations. e.g.; INSERT, DELETE, UPDATE and so on.

• Data Query Language:It is used to extract the data from the relations. e.g.; SELECT So first we will consider the Data Query Language.

• statement 1 is compulsory