SQL stands for the Structured Query Language. It is the standard language used to maintain the relational database and perform many different data manipulation operations on the data. SQL was initially invented in 1970. It is a database language used for database creation, deletion, fetching and modifying rows, etc. sometimes, it is pronounced as 'sequel.' We can also use it to handle organized data comprised of entities (variables) and relations between different entities of the data.

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SQL first appeared in 1974. It is one of the most used languages for maintaining the relational database. In 1986, SQL became the standard of the American National Standards Institute (ANSI) and ISO (International Organization for Standardization) in 1987.

• Data definition language (DDL): It defines the data structure that consists of commands like CREATE, ALTER, DROP, etc.
• Data manipulation language (DML): It is used to manipulate existing data in the database. The commands in this category are SELECT, UPDATE, INSERT, etc.
• Data control language (DCL): It controls access to the data stored in the database. The commands in this category include GRANT and REVOKE.
• Transaction Control Language (TCL): It is used to deal with the transaction operations in the database. The commands in this category are COMMIT, ROLLBACK, SET TRANSACTION, SAVEPOINT, etc.

A table is a set of organized data in the form of rows and columns. It enables users to store and display records in the structure format. It is similar to worksheets in the spreadsheet application. Here rows refer to the tuples, representing the simple data item, and columns are the attribute of the data items present in a particular row. Columns can categorize as vertical, and Rows are horizontal.

Fields are the components to provide the structure for the table. It stores the same category of data in the same data type. A table contains a fixed number of columns but can have any number of rows known as the record. It is also called a column in the table of the database. It represents the attribute or characteristics of the entity in the record.

Example

Table: Student

Field: Stud_rollno, Stud_name, Date of Birth, Branch, etc.

A database is an organized collection of data that is structured into tables, rows, columns, and indexes. It helps the user to find relevant information frequently. It is an electronic system that makes data access, data manipulation, data retrieval, data storing, and data management very easy. Almost every organization uses the database for storing the data due to its easily accessible and high operational ease. The database provides perfect access to data and lets us perform required tasks.

The following are the common features of a database:

• Manages large amounts of data
• Accurate
• Easy to update
• Security
• Data integrity
• Easy to research data