Database transaction

transactiontransactionstransactionalTransactional databasedataDatabase Transaction Controlsdatabase transactionsDemarcation transactionsshort transactionstransacted
A transaction symbolizes a unit of work performed within a database management system (or similar system) against a database, and treated in a coherent and reliable way independent of other transactions.wikipedia
164 Related Articles

Consistency (database systems)

Consistencyinconsistentconsistent
A database transaction, by definition, must be atomic, consistent, isolated and durable.
Consistency in database systems refers to the requirement that any given database transaction must change affected data only in allowed ways.

Atomicity (database systems)

atomicityatomicatomic transaction
A database transaction, by definition, must be atomic, consistent, isolated and durable.
In database systems, atomicity (from ) is one of the ACID (Atomicity, Consistency, Isolation, Durability) transaction properties.

Durability (database systems)

durabilitydurableD'''urability
A database transaction, by definition, must be atomic, consistent, isolated and durable.
In database systems, durability is the ACID property which guarantees that transactions that have committed will survive permanently.

Isolation (database systems)

isolationtransaction isolationisolated
A database transaction, by definition, must be atomic, consistent, isolated and durable.
In database systems, isolation determines how transaction integrity is visible to other users and systems.

ACID (computer science)

ACIDACID transactionsAtomicity, consistency, isolation, durability
Database practitioners often refer to these properties of database transactions using the acronym ACID.
In computer science, ACID (Atomicity, Consistency, Isolation, Durability) is a set of properties of database transactions intended to guarantee validity even in the event of errors, power failures, etc. In the context of databases, a sequence of database operations that satisfies the ACID properties (and these can be perceived as a single logical operation on the data) is called a transaction.

Rollback (data management)

rollbackrolled backroll back
If an error occurs during the transaction, or if the user specifies a rollback operation, the data manipulations within the transaction are not persisted to the database. The fundamental similarities between Relational and Object databases are the start and the commit or rollback.
They are crucial for recovering from database server crashes; by rolling back any transaction which was active at the time of the crash, the database is restored to a consistent state.

SQL

Structured Query LanguageSQL DatabasesWikibook SQL
A simple transaction is usually issued to the database system in a language like SQL wrapped in a transaction, using a pattern similar to the following:
Statements, which may have a persistent effect on schemata and data, or may control transactions, program flow, connections, sessions, or diagnostics.

Compensating transaction

Another type of transaction is the compensating transaction.
1. In the context of a database this is often easily achieved using transactions and the commit/rollback mechanism.

InnoDB

InnoDB Storage Engine
For example, MySQL began supporting transactions from early version 3.23, but the InnoDB storage engine was not default before version 5.5.
It provides the standard ACID-compliant transaction features, along with foreign key support (Declarative Referential Integrity).

Serializability

serializablerecoverabilityconflicts
The highest isolation level is serializability, which guarantees that the effect of concurrent transactions is equivalent to their serial (i.e. sequential) execution. Object databases comprise variable-sized blobs, possibly serializable or incorporating a mime-type.
In concurrency control of databases, transaction processing (transaction management), and various transactional applications (e.g., transactional memory and software transactional memory), both centralized and distributed, a transaction schedule is serializable if its outcome (e.g., the resulting database state) is equal to the outcome of its transactions executed serially, i.e. without overlapping in time.

Nested transaction

Nested transactions, for example, are transactions which contain statements within them that start new transactions (i.e. sub-transactions).
A nested transaction is a database transaction that is started by an instruction within the scope of an already started transaction.

Database

database management systemdatabasesdatabase systems
A transaction symbolizes a unit of work performed within a database management system (or similar system) against a database, and treated in a coherent and reliable way independent of other transactions. Users of database systems consider consistency and integrity of data as highly important. Databases and other data stores which treat the integrity of data as paramount often include the ability to handle transactions to maintain the integrity of data.
Operational databases store detailed data about the operations of an organization. They typically process relatively high volumes of updates using transactions. Examples include customer databases that record contact, credit, and demographic information about a business's customers, personnel databases that hold information such as salary, benefits, skills data about employees, enterprise resource planning systems that record details about product components, parts inventory, and financial databases that keep track of the organization's money, accounting and financial dealings.

Distributed transaction

distributed transactionsdistributed transaction processingglobal transactions
Database systems implement distributed transactions as transactions accessing data over multiple nodes. The Namesys Reiser4 filesystem for Linux supports transactions, and as of Microsoft Windows Vista, the Microsoft NTFS filesystem supports distributed transactions across networks.
A distributed transaction is a database transaction in which two or more network hosts are involved.

MySQL

M'''ySQLMySQL 4.1MySQL 4.x
For example, MySQL began supporting transactions from early version 3.23, but the InnoDB storage engine was not default before version 5.5.
Version 5.0: beta from March 2005, production release October 2005 (cursors, stored procedures, triggers, views, XA transactions).

Autocommit

If autocommit was disabled using, autocommit will also be re-enabled at the transaction's end.
Each individual database interaction (i.e., each SQL statement) submitted through the database connection in autocommit mode will be executed in its own transaction that is implicitly committed.

MyISAM

The earlier available storage engine, MyISAM does not support transactions.
The major deficiency of MyISAM is the absence of transactions support.

Commit (data management)

commitCommitscommitted
The fundamental similarities between Relational and Object databases are the start and the commit or rollback.
A popular usage is at the end of a transaction.

Data consistency

consistencyconsistency of the dataconsistent state
Users of database systems consider consistency and integrity of data as highly important.
Consistency (database systems) in the realm of Distributed database systems refers to the property of many ACID databases to ensure that the results of a Database transaction are visible to all nodes simultaneously.

Concurrency control

concurrencyconcurrent accessglobal concurrency control
* Concurrency control
1) This section is applicable to all transactional systems, i.e., to all systems that use database transactions (atomic transactions; e.g., transactional objects in Systems management and in networks of smartphones which typically implement private, dedicated database systems), not only general-purpose database management systems (DBMSs).

Reiser4

4
The Namesys Reiser4 filesystem for Linux supports transactions, and as of Microsoft Windows Vista, the Microsoft NTFS filesystem supports distributed transactions across networks.
Transactions support for user-defined integrity

Data integrity

integrityintegrity constraintsconstraint
Users of database systems consider consistency and integrity of data as highly important. Databases and other data stores which treat the integrity of data as paramount often include the ability to handle transactions to maintain the integrity of data.

Double-entry bookkeeping system

double-entry bookkeepingdouble-entry accountingdouble entry bookkeeping
Examples from double-entry accounting systems often illustrate the concept of transactions.

Relational database management system

RDBMSrelational database management systemsrelational database
Most relational database management systems fall into the category of databases that support transactions.

Identifier

IDidentifiersidentification number
Internally, multi-user databases store and process transactions, often by using a transaction ID or XID.

Binary large object

BLOBblobsbinary data
Object databases comprise variable-sized blobs, possibly serializable or incorporating a mime-type.