Data Manipulation Language
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Data Manipulation Language (DML) is a family of computer languages used by computer programs and/or database users to insert, delete and update data in a database. Read-only querying, i.e.
Currently the most popular data manipulation language is that of SQL, which is used to retrieve and manipulate data in a Relational database. Other forms of DML are those used by IMS/DLI, CODASYL databases (such as IDMS), and others.
Data Manipulation Language comprises the 'SQL-data change' statements, which modify stored data but not the schema or database objects. Manipulation of persistent database objects (e.g. tables or stored procedures) via the 'SQL-schema' statements, rather than the data stored within them, is considered to be part of a separate Data Definition Language. In SQL these two categories are similar in their detailed syntax, data types, expressions etc., but distinct in their overall function.
Data Manipulation Languages have their functional capability organized by the initial word in a statement, which is almost always a verb. In the case of SQL, these verbs are:
The purely read-only
Data manipulation languages tend to have many different flavors and capabilities between database vendors. There have been a number of standards established for SQL by ANSI, but vendors still provide their own extensions to the standard while not implementing the entire standard.
There are two types of data manipulation languages:
Each SQL DML statement is a declarative command. The individual SQL statements are declarative, as opposed to imperative, in that they describe what the program should accomplish, rather than describing how to go about accomplishing it.
Data manipulation languages were initially only used by computer programs, but (with the advent of SQL) have come to be used by people as well.
de:Data Manipulation Language es:Lenguaje de Manipulación de Datos eu:DML fa:زبان دستکاری دادهها fr:Langage de manipulation de données it:Data Manipulation Language nl:Data Manipulation Language ja:データ操作言語 pt:Linguagem de manipulação de dados ru:DML sq:Data Manipulation Language (DML) uk:DML zh:資料操縱語言