Database object

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A database object is a structure for storing, managing and presenting application- or user-specific data in a database. Depending on the database management system (DBMS), many different types of database objects can exist. [1] [2] The following is a list of the most common types of database objects found in most relational databases (RDBMS):

Database objects are permanent, [3] which means that they remain in their form as long as they are not explicitly changed or deleted. Application- or user-specific database objects in relational databases are usually created with data definition language (DDL) commands, which in SQL for example can be CREATE, ALTER and DROP. [4] [5]

Rows or tuples from the database can represent objects in the sense of object-oriented programming, but are not considered database objects. [6]

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Apache Empire-db is a Java library that provides a high level object-oriented API for accessing relational database management systems (RDBMS) through JDBC. Apache Empire-db is open source and provided under the Apache License 2.0 from the Apache Software Foundation.

NoSQL is an approach to database design that focuses on providing a mechanism for storage and retrieval of data that is modeled in means other than the tabular relations used in relational databases. Instead of the typical tabular structure of a relational database, NoSQL databases house data within one data structure. Since this non-relational database design does not require a schema, it offers rapid scalability to manage large and typically unstructured data sets. NoSQL systems are also sometimes called "Not only SQL" to emphasize that they may support SQL-like query languages or sit alongside SQL databases in polyglot-persistent architectures.

A graph database (GDB) is a database that uses graph structures for semantic queries with nodes, edges, and properties to represent and store data. A key concept of the system is the graph. The graph relates the data items in the store to a collection of nodes and edges, the edges representing the relationships between the nodes. The relationships allow data in the store to be linked together directly and, in many cases, retrieved with one operation. Graph databases hold the relationships between data as a priority. Querying relationships is fast because they are perpetually stored in the database. Relationships can be intuitively visualized using graph databases, making them useful for heavily inter-connected data.

PL/SQL is Oracle Corporation's procedural extension for SQL and the Oracle relational database. PL/SQL is available in Oracle Database, TimesTen in-memory database, and IBM Db2. Oracle Corporation usually extends PL/SQL functionality with each successive release of the Oracle Database.

References

  1. ↑ "Database Objects". docs.oracle.com (SQL Language Reference). Oracle. Retrieved 2023-07-05.
  2. ↑ Randolph West; et al. (2023-05-23). "sys.all_objects (Transact-SQL)". Microsoft. Retrieved 2023-07-05.
  3. ↑ Sprachen für Datenbanken. Informatik-Fachberichte. Vol. 72. 1983. p. 185. doi:10.1007/978-3-642-69297-0. ISBN   978-3-540-12733-8 – via link.springer.com.
  4. ↑ Rahul Awati (June 2022). "Data Definition Language (DDL)". techtarget.com. TechTarget. Retrieved 2023-07-10.
  5. ↑ "Generating DDL statements for database objects". ibm.com (DB2 Version 9.7 for Linux, UNIX, and Windows). International Business Machines Corporation. 2021-03-01. Retrieved 2023-07-10.
  6. ↑ Relationale Datenbanken und SQL in Theorie und Praxis. EXamen.press. 2012. p. 41. doi:10.1007/978-3-642-28986-6. ISBN   978-3-642-28985-9 – via link.springer.com.
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