User Tools

Site Tools


database_orms

Table of Contents

Database ORMs

Return to Database drivers, Programming topics, Programming languages, Software engineering topics, Software architecture, Software architecture topics, Awesome lists

Snippet from Wikipedia: Object–relational mapping

Object–relational mapping (ORM, O/RM, and O/R mapping tool) in computer science is a programming technique for converting data between a relational database and the heap of an object-oriented programming language. This creates, in effect, a virtual object database that can be used from within the programming language.

In object-oriented programming, data-management tasks act on objects that combine scalar values into objects. For example, consider an address book entry that represents a single person along with zero or more phone numbers and zero or more addresses. This could be modeled in an object-oriented implementation by a "Person object" with an attribute/field to hold each data item that the entry comprises: the person's name, a list of phone numbers, and a list of addresses. The list of phone numbers would itself contain "PhoneNumber objects" and so on. Each such address-book entry is treated as a single object by the programming language (it can be referenced by a single variable containing a pointer to the object, for instance). Various methods can be associated with the object, such as methods to return the preferred phone number, the home address, and so on.

By contrast, relational databases, such as SQL, group scalars into tuples, which are then enumerated in tables. Tuples and objects have some general similarity, in that they are both ways to collect values into named fields such that the whole collection can be manipulated as a single compound entity. They have many differences, though, in particular: lifecycle management (row insertion and deletion, versus garbage collection or reference counting), references to other entities (object references, versus foreign key references), and inheritance (non-existent in relational databases). As well, objects are managed on-heap and are under full control of a single process, while database tuples are shared and must incorporate locking, merging, and retry. Object–relational mapping provides automated support for mapping tuples to objects and back, while accounting for all of these differences.

The heart of the problem involves translating the logical representation of the objects into an atomized form that is capable of being stored in the database while preserving the properties of the objects and their relationships so that they can be reloaded as objects when needed. If this storage and retrieval functionality is implemented, the objects are said to be persistent.

External Sites

Database: Databases on Kubernetes, Databases on Containers / Databases on Docker, Cloud Databases (DBaaS). Concurrent Programming and Databases, Functional Concurrent Programming and Databases, Async Programming and Databases, Database Products (MySQL, Oracle Database, Microsoft SQL Server, MongoDB, PostgreSQL, SQLite, Amazon RDS, IBM Db2, MariaDB, Redis, Cassandra, Amazon Aurora, Microsoft Azure SQL Database, Neo4j, Google Cloud SQL, Firebase Realtime Database, Apache HBase, Amazon DynamoDB, Couchbase Server, Elasticsearch, Teradata Database, Memcached, Amazon Redshift, SQLite, CouchDB, Apache Kafka, IBM Informix, SAP HANA, RethinkDB, InfluxDB, MarkLogic, ArangoDB, RavenDB, VoltDB, Apache Derby, Cosmos DB, Hive, Apache Flink, Google Bigtable, Hadoop, HP Vertica, Alibaba Cloud Table Store, InterSystems Caché, Greenplum, Apache Ignite, FoundationDB, Amazon Neptune, FaunaDB, QuestDB, Presto, TiDB, NuoDB, ScyllaDB, Percona Server for MySQL, Apache Phoenix, EventStoreDB, SingleStore, Aerospike, MonetDB, Google Cloud Spanner, SQream, GridDB, MaxDB, RocksDB, TiKV, Oracle NoSQL Database, Google Firestore, Druid, SAP IQ, Yellowbrick Data, InterSystems IRIS, InterBase, Kudu, eXtremeDB, OmniSci, Altibase, Google Cloud Bigtable, Amazon QLDB, Hypertable, ApsaraDB for Redis, Pivotal Greenplum, MapR Database, Informatica, Microsoft Access, Tarantool, Blazegraph, NeoDatis, FileMaker, ArangoDB, RavenDB, AllegroGraph, Alibaba Cloud ApsaraDB for PolarDB, DuckDB, Starcounter, EventStore, ObjectDB, Alibaba Cloud AnalyticDB for PostgreSQL, Akumuli, Google Cloud Datastore, Skytable, NCache, FaunaDB, OpenEdge, Amazon DocumentDB, HyperGraphDB, Citus Data, Objectivity/DB). Database drivers (JDBC, ODBC), ORM (Hibernate, Microsoft Entity Framework), SQL Operators and Functions, Database IDEs (JetBrains DataSpell, SQL Server Management Studio, MySQL Workbench, Oracle SQL Developer, SQLiteStudio), Database keywords, SQL (SQL keywords - (navbar_sql), Relational databases, DB ranking, Database topics, Data science (navbar_datascience), Apache CouchDB, Oracle Database (navbar_oracledb), MySQL (navbar_mysql), SQL Server (T-SQL - Transact-SQL, navbar_sqlserver), PostgreSQL (navbar_postgresql), MongoDB (navbar_mongodb), Redis, IBM Db2 (navbar_db2), Elasticsearch, Cassandra (navbar_cassandra), Splunk (navbar_splunk), Azure SQL Database, Azure Cosmos DB (navbar_azuredb), Hive, Amazon DynamoDB (navbar_amazondb), Snowflake, Neo4j, Google BigQuery, Google BigTable (navbar_googledb), HBase, ScyllaDB, DuckDB, SQLite, Database Bibliography, Manning Data Science Series, Database Awesome list (navbar_database - see also navbar_datascience, navbar_data_engineering, navbar_cloud_databases, navbar_aws_databases, navbar_azure_databases, navbar_gcp_databases, navbar_ibm_cloud_databases, navbar_oracle_cloud_databases)


Cloud Monk is Retired (for now). Buddha with you. © 2005 - 2024 Losang Jinpa or Fair Use. Disclaimers

SYI LU SENG E MU CHYWE YE. NAN. WEI LA YE. WEI LA YE. SA WA HE.


database_orms.txt · Last modified: 2022/08/30 01:36 by 127.0.0.1