sql

SQL Structured Query Language, is a language designed to allow both technical and non-technical users query, manipulate, and transform data from a relational database. Some popular SQL databases: SQLite MySQL Postgres Oracle Microsoft SQL Server Relational database: Represents a collection of related ( two-dimensional) tables.Each of the tables are similar to an Excel spreadsheet, with a fixed number of named columns and any number of rows of data. DDL (Data Definition Language) refers to the CREATE, ALTER and DROP statements DDL allows to add / modify / delete the logical structures which contain the data or which allow users to access / maintain the data (databases, tables, keys, views…)....