18 lines
923 B
Markdown
18 lines
923 B
Markdown
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title: SQL
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---
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## SQL
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SQL stands for Structured Query Language. It is the most common tool used to create, delete, manipulate and manage data in a relational database (often referred to as a "SQL database").
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SQL is commonly pronounced "sequel." Its most popular variants are Microsoft SQL, MySQL, PostgreSQL, and SQLite - a version of SQL which is commonly used for prototyping. It introduced the concept of accessing many records with one single command, using SQL Queries.
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However, SQL code can differ between the different variants. For example, Microsoft SQL is programmed with T-SQL, which sometimes has a different syntax.
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### SQL can be divided into three parts:
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1. The Data Manipulation Language (DML) is for working with the database tables.
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2. The Data Definition Language (DDL) is for working with the data in the tables.
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3. The Data Control Language (DCL) is for access control to the database.
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