Overview of SQL¶
SQL stands for Structured Query Language and it is broadly categorized into following:
DDL - Data Definition Language
Creating Database Objects such as Tables, Indexes etc.
Define constraints such as not null, primary key, foreign key etc.
DML - Data Manipulation Language
Inserting or Updating data in the tables
Deleting data from the tables
DQL - Data Query Language
Project the data
Filter based up on the requirements
Join multiple tables
TCL - Transaction Control Language
Commit to persistently store the changes.
Rollback to revert back changes to the prior state.
Typically as part of applications we perform CRUD Operations which are nothing but DML and DQL.