Oracle Fachvokabular

The physical files on disk that store the transaction recovery information written from the redo log buffer by the LGWR (log writer) process. See also log writer (LGWR).

The portion of the system global area (SGA) where transaction recovery information is stored until it can be written to the redo log files. See also system global area (SGA).

One of the files that constitutes a redo log group. This is also referred to as a redo log member.

A collection of multiplexed (mirrored) redo log files that contain information about changes in the database.

One of the redo logs within a redo log group.

Enforcing business rules within or between tables using primary key constraints and foreign key constraints.

An intermediate point within a transaction to which changes can be rolled back, without rolling back the entire transaction.

The ability of a system to continue to provide adequate performance as the amount of data, the number of users, or both increases.

A subquery that returns one row and one column value. If the scalar subquery returns no rows, the resulting value is NULL.

One or more SQL and/or SQL*Plus commands saved in a file for reuse.

A schema object that stores data outside the data dictionary. Tables and indexes are segments, while constraints and sequences are not.

Defines how free space within a segment is managed.

The SQL statement used to query data. This is the most commonly used statement in Oracle.

A join in which a table is joined to itself in a query.

A foreign key constraint that refers to the primary key column of the same table.

A named sequential-number generator.

A binary, dynamically modifiable file that stores a list of instance configuration parameters.

The operating-system process that executes on the host server on behalf of the user. The server process is responsible for parsing and placing SQL statements into the shared pool, copying database blocks into the database buffer cache, and placing transactionrecovery information into the redo log buffer.

The term used to describe a user’s connection to an instance.

Operators used to write compound queries. UNION, UNION ALL, MINUS, and INTERSECT are the set operators.

Another name for a dedicated server process. See also shared server process.

A table lock that will block all changes to data and exclusive locks but will allow other share locks.

A packet sent via TCP/IP that acknowledges the refusal of some network request.

A location in the system global area (SGA) in an Oracle Shared Server environment in which the dispatcher process places client requests. The shared server process then processes these requests. See also system global area (SGA).

The location in the system global area (SGA) in an Oracle Shared Server environment where a shared server process places a completed client request. The dispatcher process then picks up the completed request and sends it back to the client.

The time it takes for a single user’s request to return the desired result while using an application. Frequently used as a performance measure in data warehouse systems.

A join between two tables that returns rows based on the matching condition, as well as unmatched rows from the table to the right of the JOIN clause.

A mechanism for grouping privileges for ease in administering them.

A database privilege that, by proxy, gives the grantee any combination of object, system, or other role privileges. Some role privileges that are included with all Oracle databases are DBA, resource, and java_admin.

The first phase of instance recovery, during which information in the online redo log files is applied to the data files (including the undo tablespace) to bring the data files up to their state before the instance failed.

The SQL statement to undo a transaction.

The second phase of instance recovery, during which uncommitted transactions are backed out from the data files.

Manually managed segments for storing undo information. This information is used for read consistency and recovery purposes. Rollback segments were replaced by system-managed undo segments when automatic undo management was used.

The process of undoing one or more changes to data within a transaction.