Data Query Language
DATA QUERY LANGUAGE(DQL)
Introduction
Data Query
Language (DQL) is a set of commands used to retrieve, filter, and manipulate
data from databases. It allows users to query databases and extract specific
information based on their requirements.
What is DQL?
Data Query
Language (DQL) is one of the basic sub-languages of SQL statements. There are
generally four categories in SQL languages which are data query language (DQL),
data definition language (DDL), data control language (DCL), and data
manipulation language(DML). It is also occasionally suggested that a
transaction control language (TCL) belongs in the sub-language set.
DQL
statements are employed to conduct inquiries on the information contained in
schema objects. The required data is retrieved according to the query using
Data Query Language (DQL) commands.
Data Query Language (DQL)
refers to a language or set of commands used to query databases and retrieve
specific data. DQL is typically associated with database management systems
(DBMS) and provides a way to interact with databases to perform various
operations. Here are some common uses of DQL:
1. Data
Retrieval: The primary use of DQL is to retrieve data from a database. By using
DQL commands such as SELECT, users can specify the criteria and conditions to
retrieve specific data records or fields. DQL allows you to query databases to
obtain the information you need for analysis, reporting, or application
development.
2. Filtering
and Sorting: DQL enables filtering and sorting of data based on specific
conditions. You can use DQL commands like WHERE to specify conditions that
filter data based on certain criteria, such as dates, values, or text patterns.
DQL also supports sorting data using ORDER BY, allowing you to arrange query results
in ascending or descending order based on one or more columns.
3. Aggregation
and Grouping: DQL provides functionality for aggregating and summarizing data.
You can use aggregate functions like COUNT, SUM, AVG, MAX, and MIN to perform
calculations on groups of data. DQL also allows you to group data based on one
or more columns using the GROUP BY clause, enabling the creation of summary
reports or analysis based on different categories.
4. Joining
Multiple Tables: DQL allows you to combine data from multiple tables using join
operations. By specifying join conditions, you can merge data from related
tables into a single result set. This is particularly useful when you need to
extract data that is distributed across different tables and establish
relationships between them.
5. Data
Modification: Although the primary focus of DQL is querying and retrieving
data, some database systems also provide DQL commands to modify data. For
example, you can use DQL commands like INSERT, UPDATE, and DELETE to add,
modify, or remove data records in a database.
6. Data
Definition: DQL can also be used for defining and managing the structure of
databases. DQL commands like CREATE TABLE, ALTER TABLE, and DROP TABLE are used
to create, modify, and delete database objects such as tables, indexes, and
constraints.
7. Database
Administration: DQL is also utilized for database administration tasks.
Database administrators use DQL to manage user permissions and access
privileges, create and maintain database schemas, optimize query performance,
and perform other administrative functions necessary for the efficient
operation of a database system.
Conclusion
Thus this is how Data
Query Language (DQL) is used.
Data Bending
Databending is the process of manipulating a media file of a certain format, using software designed to edit files of another format.
Distortions in the medium typically occur as a result, and the process is
frequently employed in glitch art.
Reference
1.
https://www.javatpoint.com/data-query-language
2.
https://en.wikipedia.org/wiki/Databending
Hitansh Lakkad
Business Analytics
intern at Hunnarvi Technologies Pvt Ltd in collaboration with nanobi analytics.
VIEWS ARE PERSONAL
#Bigdata#analytics#datastorage#datamanagement#datastorage#DQL#databending
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