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An example of a database abstraction layer on the language level would be ODBC that is a platform-independent implementation of a database abstraction layer. The user installs specific driver software, through which ODBC can communicate with a database or set of databases. The user then has the ability to have programs communicate with ODBC ...
In software, a data access object (DAO) is a pattern that provides an abstract interface to some type of database or other persistence mechanism. By mapping application calls to the persistence layer, the DAO provides data operations without exposing database details. This isolation supports the single responsibility principle.
An example of this abstraction process is the generational development of programming language from the machine language to the assembly language and the high-level language. Each stage can be used as a stepping stone for the next stage. The language abstraction continues for example in scripting languages and domain-specific programming languages.
For example, the DAL might return a reference to an object (in terms of object-oriented programming) complete with its attributes instead of a row of fields from a database table. This allows the client (or user) modules to be created with a higher level of abstraction. This kind of model could be implemented by creating a class of data access ...
Application programs should not, ideally, be exposed to details of data representation and storage. The DBMS provides an abstract view of the data that hides such details. [2] There are two types of data independence: physical and logical data independence. The data independence and operation independence together gives the feature of data ...
Sources and destinations include different database backends, file formats like .csv, XML and spreadsheets. Even untidy HTML web pages can be used as both a source and destination. For SQL/RDBMS backends, it has a database abstraction layer that supports basic connectivity to Postgres, MySQL / MariaDB, IBM Db2, Oracle and MS SQL Server. [4]
The internal structure of the database should be unaffected by changes to the physical aspects of the storage: For example, a changeover to a new disk. The three levels are: External Level (User Views): A user's view of the database describes a part of the database that is relevant to a particular user. It excludes irrelevant data as well as ...
An abstract data type that represents a sequence of values, where the same value may occur more than once. Data order maintenance, implementation of stacks, queues, etc. Stack: A collection that supports a last-in, first-out access pattern. Function calls/recursive calls, undo mechanisms in applications. Queue