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Data Query Language (DQL) is part of the base grouping of SQL sub-languages. These sub-languages are mainly categorized into four categories, DDL, DQL, DML and DCL. Sometimes TCL is argued to be part of the sub-language set as well.

DQL statements are used for performing queries on the data within schema objects. The purpose of DQL commands is to get the schema relation based on the query passed to it.

Although often considered part of DML, the SQL SELECT statement is strictly speaking an example of DQL. When adding FROM or WHERE data manipulators to the SELECT statement the statement is then considered part of the DML.

Related languages

Data definition language
Data manipulation language
Data control language
Transactional Control Language

v t e Database
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Languages	Data definition Data manipulation Query information retrieval
Security	Activity monitoring Audit Forensics Negative database
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Programming	Abstraction layer Object-relational mapping
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See also	Database-centric architecture Intelligent database Two-phase locking Locks with ordered sharing Load file Publishing Halloween Problem Log shipping
Book Category WikiProject

v t e Database management systems
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