Glossary | Oracle 9i Fundamentals I Exam Cram 2

Appendix. Glossary

O7_DICTIONARY_ACCESSIBILITY: Intended for use when migrating from Oracle 7 to Oracle 9i, controls restrictions on the SYSTEM privileges. If set to TRUE, full access to objects in the SYS schema is allowed. Default is FALSE meaning that SELECT ANY and EXECUTE ANY are limited to those with appropriately granted privileges.

ACCOUNT LOCK: ALTER USER parameter used to lock a user account.

ACCOUNT UNLOCK: ALTER USER parameter used to unlock a user account.

ADMINISTER_RESOURCE_MANAGER: System privilege granted using the DBMS_RESOURCE_MANAGER_PRIVS package rather than through a typical GRANT statement.

Alert log: Chronological file providing information on errors, log switches, startup, shutdown, and system level changes in the database. A chronological log of messages and errors from the database. Oracle automatically creates a new one when the old one gets deleted.

ALL_ views: Data dictionary views that provide information on all objects to which the currently logged in user has access. This provides not only all the objects owned by the user but also the objects to which the user has been granted access.

ALL_DEF_AUDIT_OPTS: Dictionary view providing audit options for all objects.

ALTER DATABASE: Command used to alter the state of the database.

ALTER INDEX: Command used to alter indexes.

ALTER SYSTEM: Command used to alter the state of the instance.

ALTER TABLE: Command used to alter tables.

ALTER TABLESPACE: Command used to alter the storage parameters of the tablespace.

ALTER USER: Command used to alter users.

Alternate key: Key other than the primary key for the table, also known as subordinate key.

Analyze: Process of gathering statistics on database objects.

ANSI: American National Standards Institute, a privately funded nonprofit organization that coordinates development and approval of entirely voluntary standards in the United States.

ARCHIVELOG: Mode of running the database in which filled redo logs are archived into archive logs before the redo logs can be reused. This mode is used to ensure that complete database recovery can be accomplished.

ARCHIVELOG MODE: Mode of running the database in which filled redo logs are archived into archive logs before the redo logs can be reused. This mode is used to ensure that complete database recovery can be accomplished.

Archiver (ARCH): Background process started when you start the database in archive log mode.

Archiving: The copying of redo log files to an alternative archival destination. The archival is handled by the ARCH process, which should be turned on to ARCHIVELOG MODE to facilitate online backups of the database.

ASCII: The American Standard Code for Information Interchange (ASCII) is used extensively for data transmission. The character set includes 128 upper- and lowercase letters, numerals, and special characters each encoded by unique 7-bit numbers.

Attribute: The portions of a entity that store the pieces of information about an object. Attributes equate to the columns of a table and typically contains atomic values.

AUDIT: An Oracle command that controls the auditing of objects, statements, or privileges.

Auditing: The process of recording database activity and access to objects as it occurs in the database.

Authentication: Process of determining whether someone or something is what it claims to be.

Authorization: Granting of authority typically based on access rights.

Automatic Segment Space Management: Mode of operation in which Oracle manages free space in segments automatically.

background_dump_dest: Initialization parameter specifying the location, either directory or drive specification, where the debugging trace files from the background processes are written during Oracle operations. Also the location of the alert log file.

Background processes: Oracle processes that maintain the operation of the database. These processes consolidate functions that would otherwise be handled by multiple Oracle programs running for each user process. The background processes asynchronously perform I/O and monitor other Oracle processes to provide increased parallelism for better performance and reliability.

Block: A unit of data transfer between main memory and disk. Many blocks from one section of memory address space form a segment.

Block header: Portion of the block containing control information.

Bootstrap segment: An Oracle data block in the SYSTEM tablespace that contains code used to start a database.

Buffer: A main memory address in which the buffer manager caches currently and recently used data read from disk. Over time, a buffer can hold different blocks. When a new block is needed, the buffer manager can discard an old block and replace it with a new one.

Buffer cache: The portion of the SGA that holds copies of data blocks read from data files. All user processes concurrently connected to the instance share access to the database buffer cache.

Buffer pool: A collection of buffers.

BUFFER_POOL_KEEP: Lets you save objects in the buffer cache by setting aside a portion of the total number of buffers from the allocated number in the DB_BLOCK_BUFFERS parameter as a KEEP buffer pool.

BUFFER_POOL_RECYCLE: Deprecated in favor of the DB_RECYCLE_CACHE_SIZE parameter. BUFFER_POOL_RECYCLE lets you limit the size of objects in the buffer cache by setting aside a portion of the total number of buffers from the allocated value of the DB_BLOCK_BUFFERS parameter as a RECYCLE buffer pool.

Cache: Also known as buffer cache. All buffers and buffer pools.

Cache recovery: The part of instance recovery where Oracle applies all committed and uncommitted changes in the redo log files to the affected data blocks. Also known as the rolling forward phase of instance recovery.

catalog.sql: Script used for creating the data dictionary views.

Character set: An encoding scheme in which each character is represented by a different binary value.

Checkpoint: Occurs when the database writer process writes all modified buffers in the buffer cache to the data files. Checkpoints occur after every log switch and also at intervals specified by initialization parameters.

Cluster segment: Database segment used for storing clusters.

Cluster tables: Optional structure for storing table data. Clusters are groups of one or more tables physically stored together in the same data block because they share common columns and are often used together. Because related rows are physically stored together, disk access time will be significantly improved.

COMPOSITE_LIMIT: In resource manager, a weighted sum, measured in service units, of certain resources.

CONNECT_TIME: Resource manager parameter used to specify the total elapsed time limit for a session, expressed in minutes.

CONTROL_FILE: An Oracle proprietary file that records the physical structure of a database and contains the database name, the names and locations of associated databases and online redo log files, the time stamp of the database creation, the current log sequence number, and checkpoint information. At least one control file is necessary to start an Oracle instance.

core_dump_dest: Primarily a Unix initialization parameter specifying the location where Oracle will write core dump files. May not be supported on all platforms.

CPU_PER_CALL: Resource manager parameter used to specify the CPU time limit for an individual call (for example, a parse, execute, or fetch). Parameter is expressed in hundredths of seconds.

CPU_PER_SESSION: Resource manager parameter used to specify the CPU time limit for a session. Parameter is expressed in hundredths of seconds.

CREATE_BITMAP_AREA_SIZE: Specifies the amount of memory in bytes that will be allocated for bitmap creation. Relevant only for systems using bitmap indexes. Oracle recommends using this parameter only if also using the shared server option. Retained only for backward compatibility.

CREATE BITMAP INDEX: Command used to create bitmap indexes in the database.

CREATE DATABASE: Command issued to create a new database.

CREATE INDEX: Command used to create indexes in the database.

CREATE TABLESPACE: Command used to create a tablespace in the database.

CREATE UNDO TABLESPACE: Command used to create the undo tablespace in the database.

CREATE UNIQUE INDEX: Command used to create unique indexes in the database.

CREATE USER: Command used to create users in the database.

Data block: Smallest logical unit of data storage in an Oracle database. Also known as logical blocks, Oracle blocks, or pages. One data block corresponds to a specific number of bytes of physical database space on disk and is defined by number of kilobytes.

Data dictionary: The core set of tables and views used as a read-only reference about the database in which they appear. The data dictionary contains information such as the logical and physical structure of the database, valid users of the database, information about integrity constraints, how much space has been allocated for any given schema object, and how much of this allocated space is in use. The data dictionary is created when the database is created and is automatically updated whenever the structure of the database is changed.

Data file: A physical operating system file on disk that was created by Oracle, is associated with exactly one tablespace, and contains data structures such as tables and indexes. A data file can only belong to one database.

Data segment: Each nonclustered table has a single dedicated data segment. All the table's data is stored in the extents of its data segment. For a partitioned table, each partition has its own data segment. Each cluster has a single data segment defined for it. The data of every table in the cluster is stored in the cluster's single data segment.

Data warehouse: Typically, a very large database on which decision support systems run.

Database: A collection of data treated as a unit. Stores and provides retrieval capability for related information.

Database buffer cache: Memory structure in the system global area that stores the most recently used blocks of data.

Database Writer (DBWn): Oracle background process that writes the contents of the buffers to data files. Responsible for writing modified (or dirty) buffers in the database buffer cache to disk.

Date time formats: Specific format of the date and time presented to the user.

DB_BLOCK_BUFFERS: The number of database buffers in the buffer cache. Parameter deprecated in favor of DB_CACHE_SIZE.

DB_BLOCK_SIZE: Default block size in bytes of the database. Can only be specified at databasecreation time, and if it is necessary to change this parameter, the database must be re-created. Defaults to 2KB if left unspecified. Block size of the SYSTEM tablespace.

DB_CACHE_SIZE: Specifies the size of the DEFAULT buffer pool used for those buffers with the primary block size as defined by the DB_BLOCK_SIZE parameter. Size must be at least one granule.

DB_CREATE_FILE_DEST: Sets the default value for where Oracle will create its files if you are using Oracle managed files (OMFs). Can be altered with either the ALTER SYSTEM or ALTER SESSION command. Directory must already exist before you specify this parameter and must have appropriate permissions.

DB_CREATE_ONLINE_LOG_DESTn: Default location for Oracle managed redo log files and control files where n is any integer between 1 and 5 inclusive. At least two should be specified for fault tolerance. Alterable with ALTER SYSTEM or ALTER SESSION. Directory has to already exist before parameter is set and must have appropriate permissions.

DB_DOMAIN: Specifies the logical location of the database within the network. Should be set if database will ever be part of a distributed environment. Oracle recommends that each database in the system have its own unique DB_DOMAIN.

DB_FILES: Specifies the number of data files that can be open in the database. Default value is 200. Maximum value is operating system dependent. Can be changed after database creation, but requires database restart.

DB_KEEP_CACHE_SIZE: Specifies the size of the keep buffer pool in megabytes, kilobytes, or gigabytes and is based on primary blocks. If defined, must be at least one granule. Maximum size is operating system dependent.

DB_NAME: Parameter that must be specified for every instance. Specifies database identifier of up to eight characters and must correspond to the name specified in the CREATE DATABASE statement. Although optional, should be set at the environment level before creating the database and then referenced in that statement.

DB_nK_CACHE_SIZE: specifies the size of the cache for the nK buffers to be used when tablespaces with block sizes other than the default block size are used in the database.

DB_RECYCLE_CACHE_SIZE: Specifies the size of the recycle buffer pool. Sized in kilobytes, megabytes, or gigabytes and based on the default block size for the database. Minimum if set is one granule. Maximum size is operating system dependent.

DB_WRITER_PROCESSES: Specifies the initial number of database writer processes for a system. Defaults to 1 and can take on any number from 1 to 20. Particularly useful for systems that have heavy data modification characteristics.

DBA_ views: DBA_ views provide information on database objects across all schemas. DBA_ views can, and typically do, contain more columns than the corresponding ALL_ or USER_ views.

DBA_AUDIT_EXISTS: Data dictionary view that lists audit trail entries produced by AUDIT NOT EXISTS and AUDIT EXISTS.

DBA_AUDIT_OBJECT: Data dictionary view that holds the audit trail records for statements concerning objects, specifically, table, cluster, view, index, sequence, public database link, public synonym, procedure, trigger, rollback segment, tablespace, role, and user.

DBA_AUDIT_SESSION: Data dictionary view that holds all audit trail records concerning CONNECT and DISCONNECT.

DBA_AUDIT_STATEMENT: Data dictionary view that holds audit trail records concerning grants, revokes, audit, NOAUDIT, and ALTER SYSTEM.

DBA_AUDIT_TRAIL: Data dictionary view containing all audit trail entries.

DBA_COL_PRIVS: Data dictionary view containing all grants on columns in the database.

DBA_DATA_FILES: Data dictionary view containing information about all data files in the database.

DBA_IND_COLUMNS: Provides information on all indexed columns in the database.

DBA_INDEXES: Provides information on all indexes in the database.

DBA_OBJ_AUDIT_OPTS: Data dictionary view containing auditing options for all tables and views.

DBA_OBJECTS: Provides information, including status, on all objects in the database.

DBA_PRIV_AUDIT_OPTS: Data dictionary view that describes current system privileges being audited across the system and those being audited by users.

DBA_ROLE_PRIVS: Data dictionary view that provides information concerning roles that have been granted to users and two other roles.

DBA_ROLES: Data dictionary view that provides information concerning all the roles that exist in the database.

DBA_ROLLBACK_SEGS: Data dictionary view that provides information concerning the description of rollback segments.

DBA_STMT_AUDIT_OPTS: Data dictionary view that describes the current system auditing options enabled both by the system and by the user.

DBA_SYS_PRIVS: Data dictionary view that contains information concerning system privileges granted to users and roles.

DBA_TAB_PRIVS: Data dictionary view that contains information concerning all grants on all objects in the database.

DBA_TABLESPACES: Data dictionary view containing information concerning the description of all tablespaces.

DBA_TEMP_FILES: Data dictionary view containing information concerning all-time files in the database. These are connected to both the default temporary tablespaces and any other temporary tablespaces defined in the database.

DBMS_RESOURCE_MANAGER: Oracle provided package that maintains plans, consumer groups, and plan directives, while also providing the semantics so that you may group together changes to the plan schema.

DBMS_SESSION.SET_ROLE: Package that provides access to SQL ALTER SESSION and SET ROLE statements, as well as other session information, from PL/SQL. You can use this to set preferences and security levels.

DEALLOCATE UNUSED: Clause used to explicitly deallocate unused space at the end of a database object segment and make the space available for other segments in the tablespace.

Decision Support System (DSS): Database architecture typified by large volumes of data and primarily read-only access. Also often referred to as data warehouses.

DEFAULT PROFILE: Profile assigned to a user if no profile is deliberately assigned to the user.

DEFAULT ROLE: The role or roles enabled at user login time.

Disable: Operation that you can take on an constraint to allow the insertion of data that may or may not pass the constraint test into the database.

DISABLE NOVALIDATE: Constraint state in which the data is not checked and the constraint condition is not necessarily true.

DISABLE VALIDATE: Constraint state that disables the constraint, drops the index on the constraint, and disallows any modification of the constrained columns.

Dispatcher: Background process in a shared server architecture. Responsible for directing request to server process to be handled and the data to be retrieved.

DROP INDEX: Command for removing an index from a table.

Dynamic performance view: Name for the V$ views in the data dictionary that provide dynamic tuning information for the current database state.

Enable: Constraint or role status.

ENABLE NOVALIDATE: Constraint is checked, but it does not have to be true for all rows and allows existing rows to violate the constraint rule, while ensuring that all new or modified rows are valid.

ENABLE VALIDATE: Constraint is checked and is guaranteed to hold for all rows.

EXPIRED: Condition of a password in which the password needs to be changed.

Extent: A specific number of contiguous data blocks allocated for storing a specific type of information (table, index, cluster).

External tables: Operating system flat files accessed using SQL statements as if they were normal tables. Cannot be indexed and cannot have INSERT, UPDATE, or DELETE operations performed.

EXTERNALLY: Authentication option for the CREATE USER statement.

FAILED_LOGIN_ATTEMPTS: Maximum number of failed login attempts for the user. After this number, the account becomes locked.

GLOBAL_NAME: Global database name.

Grant: Means by which you attach privileges or roles to a user or privileges to a role.

High water mark: A special marker used by Oracle to indicate the last block used to hold a table's data.

IDLE_TIME: Maximum amount of time, in minutes, that a user session can be idle without being disconnected.

IFILE: File used to embed one parameter file in another. Several IFILEs can be embedded in a single parameter file, and up to three levels of nesting is possible.

Index: Object that lets you quickly locate particular records based on key column values.

Index organized table segment: Database segment allocated to index organized tables.

Index organized tables: Type of table in which all the data is stored in a B-tree index structure.

Index partition segment: Segment allocated to a partition of a partitioned index.

Index segment: Segment allocated to an index.

Initialization parameter file: File providing static initialization parameters that Oracle reads at instance startup. Naming convention is init<SID>.ora.

Java pool: Location from where Java memory manager allocates most Java statements during runtime operation.

JAVA_POOL_SIZE: Size, in bytes, of Java pool.

Language support: Global support for multiple languages.

Large pool: Memory area of the SGA mainly used when running in Shared Server mode and for buffering sequential file I/O when using recovery manager (RMAN).

LARGE_POOL_SIZE: Specification for the size (in kilobytes or megabytes) of the large pool, used in shared server architecture.

Library cache: Memory area of the SGA where Oracle stores table information, object definitions, and SQL statements.

Linguistic sorting: Alternative method of sorting that takes into account NLS territories.

LOB: Large object Binary.

LOB segment: Database segment used for storing large objects.

Locally managed tablespace: Tablespace managed with bitmap segments internally to the tablespace rather than in the data dictionary.

LOG_BUFFER: Amount of memory in bytes that Oracle uses when buffering redo entries to a redo log file. Larger values typically mean reduced log file I/O. In a busy system, values of 65536 or higher are perfectly reasonable.

LOG_CHECKPOINT_INTERVAL: Frequency of checkpoints in terms of the number of redo log file blocks that can exist between an incremental checkpoint and when the last block was written to the redo logs. Number specifies operating system blocks, not database blocks.

LOG_CHECKPOINT_TIMEOUT: Frequency in seconds of the amount of time that has passed since the incremental checkpoint and the point where the last write to the redo log files occurred. Also specifies that there will be at most this many seconds that any buffer will remain dirty. Default value is 1,800 seconds.

LOGICAL_READS_PER_CALL: Maximum number of database blocks read per call.

LOGICAL_READS_PER_SESSION: Maximum number of database blocks read per session.

Log Writer (LGWR): Background process that writes the redo log buffers out to the online redo log files.

Manual Segment Space Management: Space management mode in which the allocation of extents and extent sizing are managed by the DBA.

MAX_DUMP_FILE_SIZE: Maximum size that Oracle will write to a dump file. If the potential dump file would have exceeded this size, Oracle truncates trailing information that is often relevant.

MAXDATAFILES: Maximum number of data files allowed in the database. Alteration of this parameter requires database restart.

MAXEXTENTS: Maximum number of extents in a segment.

MAXLOGFILES: Maximum number of redo log groups.

MAXLOGHISTORY: Permanent database parameter used to specify the maximum number of log switches. This is set in the CREATE DATABASE statement, alterable only with a database re-creation or a control file re-creation.

MAXLOGMEMBERS: Maximum number of log members per redo log file group.

Message support: Multilanguage support for messages, associated with globalization and multilanguage support.

MINEXTENTS: Minimum number of extents allocated to a segment.

Monetary forms: Multilanguage support for different monetary units, associated with globalization and multilanguage support.

National Language Support (NLS): Support in the database for languages other than the base language chosen for the database.

Nested table segment: Segment used to store nested table's base table.

NLS_CALENDAR: Specifies the calendar system that Oracle will use. Valid values include Arabic Hijra, English Hijra, Gregorian, Japanese Imperial, Persian, Republic of China Official, and Thai Buddha.

NLS_COMP: National Language comparison. Normally when Oracle does comparisons in the WHERE clause and within PL/SQL blocks, the comparisons are binary unless you specify the NLSSORT function. By setting NLS_COMP to ANSI, you indicate to Oracle that all comparisons of this type should use the linguistic sort specified in the NLS_SORT parameter. One caveat is, however, that you must also define an index on the column for which you want Oracle to perform these linguistic sorts.

NLS_DATE_FORMAT: Default format to use when the TO_CHAR or TO_DATE functions are called. The default value is determined by the value to which NLS_TERRITORY is set.

NLS_DATE_LANGUAGE: Language used for spelling out day and month names and abbreviations (a.m., p.m., AD, BC) that gets returned by the TO_DATE and TO_CHAR functions.

NLS_DUAL_CURRENCY: Specifies the dual currency symbol, for example the Euro, that is used for the given territory. The default dual currency symbol is the symbol defined for the territory of your current language environment and is derived from the NLS_TERRITORY setting.

NLS_ISO_CURRENCY: String to use as the international currency symbol for a number element. Ambiguity can be introduced because the dollar sign ($) can refer to US dollars, Canadian dollars, or Australian dollars.

NLS_LANGUAGE: Defines the default language of the database. Language is used for messages, date names and symbols, and for the default sorting mechanism. This parameter helps to determine the values for NLS_DATE_LANGUAGE and NLS_SORT.

NLS_LENGTH_SEMANTICS: Enables you to create CHAR and VARCHAR2 columns that are either byte-based or character-based. Existing columns are not affected.

NLS_NUMERIC_CHARACTERS: Derived from NLS_TERRITORY, this parameter determines the symbol to use as the group and decimal separator.

NLS_SORT: Specifies the collating sequence for ORDER BY queries. Setting this parameter to anything other than binary forces sorts to do full table scans.

NLS_TERRITORY: Name of the territory whose conventions are to be used for date and week numbering. Determines the default date format, default decimal character, group separator, International Standards Organization (ISO), and local currency symbols.

NLS_TIMESTAMP: Default time stamp format to use with the TO_CHAR and TO_TIMESTAMP functions.

NLS_TIMESTAMP_TZ_FORMAT: Default time stamp with time zone format to be used with TO_CHAR and TO_TIMESTAMP functions.

NOARCHIVELOG: Mode in which Oracle does not require the redo logs to be archived before they are overwritten.

Nonstandard block size: Block size of database tables that are not the standard block size as defined by DB_BLOCK_SIZE.

Numeric formats: Multilanguage support for different forms of numeric output (dots versus commas and so forth), associated with globalization and multilanguage support.

Object privileges: Privileges granted on specific objects.

Online redo log files: A mandatory set of two or more files that record all changes made to an Oracle database.

Online Transaction Processing (OLTP) system: Database typified by a large number of inserts, updates, and deletes.

Optimal Flexible Architecture: Recommendations for naming files and folders when installing and implementing an Oracle database.

OPTIMIZER_MODE: Establishes default behavior for choosing optimizer approach for the instance.

ORACLE_BASE: The root of the Oracle directory tree or the uppermost directory under which the Oracle software is installed.

Oracle database: A structured collection of data. The database is the collection of data files and supporting files that allow users to access their data.

Oracle Database Configuration Assistant (DBCA): Utility for creating, configuring, and removing Oracle databases.

ORACLE_HOME: Corresponds to the environment from which the individual Oracle products run. This environment includes the location of installed product files and is referenced by the PATH variable pointing to the binary files of installed products.

Oracle instance: The set of supporting memory structures and processes associated with a database.

Oracle Server: Oracle installed files along with the database and instance.

ORACLE_SID: Environment variable that holds the Oracle System Id. This corresponds to the database name that you want to attach to.

Oracle Universal Installer: Oracle Java-based utility used to install Oracle software.

OS_AUTHENT_PREFIX: Specifies the prefix that Oracle uses with which to authenticate users attempting to connect to the database using OS Authentication. Oracle concatenates the value of this parameter to the beginning of the given user's operating system account name and password whenever a connection request is attempted. Oracle compares the prefixed username with Oracle usernames in the database.

PASSWORD EXPIRE: CREATE USER clause used to force the new user's password to automatically be expired, forcing that user to have to change the password on first login.

Password file: Stores passwords for users with administrative (SYSDBA and SYSOPER) privileges.

PASSWORD_GRACE_TIME: Resource profile parameter providing the user with the number of days of grace allowed after a password has expired and before the account automatically locks. Users enter the grace period on the first attempt to log in to the database account after the password has expired. During the grace period, a warning message appears each time users try to log in to their account until the grace period expires. Users must change the password within the grace period; if not, the users are prompted for a new password each time an attempt is made to access their account, and access is denied until a new password is supplied.

PASSWORD_LIFE_TIME: Number of consecutive days that a password is allowed to remain unchanged.

PASSWORD_LOCK_TIME: Resource Manager profile parameter reflecting the amount of time that must pass before the user can retry to log in after the account has been temporarily locked due to invalid logins.

PASSWORD_REUSE_MAX: Number of password changes required before the current password can be reused.

PASSWORD_VERIFY_FUNCTION: Function (either Oracle provided or customized by implementation) used to verify passwords to the database.

pctincrease: Percent that you want each additional extent to be grown over the size of the last extent allocated to a segment.

Pending area: Database Resource Manager area to which modifications to a resource plan schema are posted first and validated prior to being submitted to the Oracle database.

PRIVATE_SGA: Name of the function used for password verification for profiles.

Process Monitor (PMON): Oracle background process responsible for performing process recovery whenever a user process fails and for cleaning up the cache and freeing resources that the failed process was using. PMON is also responsible for checking on dispatcher and server processes and restarting them if they have failed.

Program global area (PGA): A memory buffer, created when a server process is started, that contains data and control information for the server process.

QUOTA: Amount of space that a given user is permitted in a tablespace or the amount of other resources that a user is permitted via a profile.

REBUILD: Operation to perform on indexes; can be performed online or offline.

Recoverer: Background process responsible for resolving in-doubt transactions across distributed databases.

Recovery manager (RMAN): A tool that automates and manages the backup and recovery of Oracle databases.

Redo log buffer: Circular buffer in the SGA containing information about changes made to the database.

Redo log groups: Set of one or more (multiplexed) files where Oracle records the changes to the database as they are made. In the event of an instance failure, Oracle reads these files to recover the database. These also track the rollback segments in the database. At least two groups are required, and at least three are suggested.

Redo log members: The individual files within the redo log groups.

Regular tables: Tables in which user data is usually stored with the database.

REMOTE_OS_AUTHENT: Specifies whether remote clients will be authenticated with the value of OS_AUTHENT_PREFIX.

Resource consumer groups: Database Resource Manager construct that allows the database administrator to group user sessions together based on their resource requirements.

Resource directives: Database Resource Manager construct used as a means of assigning consumer groups to particular plans and partitioning resources out among different consumer groups by specifying parameters for each resource allocation method.

RESOURCE_LIMIT: Boolean parameter that determines whether resource limits are enforced in the database with profiles.

RESOURCE_MANAGER_PLAN: Top-level plan to use for an instance. The resource manager will load this top-level plan and all its descendants. If you don't specify this parameter, resource manager is disabled. You can change this setting with the ALTER SYSTEM command. If the plan specified does not exist in the data dictionary, Oracle returns an error.

Resource plans: Database Resource Manager construct used as a means of specifying how the resources are to be distributed among various users in various resource consumer groups.

REVOKE: Removes roles or privileges from users or privileges from roles.

ROLE_ROLE_PRIVS: Data dictionary view providing information about roles that have been granted to roles.

ROLE_SYS_PRIVS: Data dictionary view providing information about system privileges that have been granted to roles.

ROLE_TAB_PRIVS: Data dictionary view providing information about table privileges granted to roles.

Rollback: Activity performed by Oracle to restore data to its state prior to a point where a user started to change it.

Rollback segment: Location where UNDO is managed in manual undo managed database.

Row data: Data retrieved from schema tables.

ROWID: Oracle created and maintained pseudo-column value representing the physical location on disk where the record is stored.

Scalar data types: Simple data types, referencing a single value, cannot be further subdivided into components. In Oracle these are number, char, varchar2, long, and date.

Schema: Equivalent to user. Location under which a user's objects are created.

Schema objects: Database objects (tables, indexes, clusters, and so on) that reside in a user's schema.

Segment: Oracle construct consisting of one or more extents allocated within a tablespace and containing objects.

SESSION: Parameter that specifies the maximum number of sessions that can be created in a system. The default value is derived with the following formula ((1.1 * PROCESSES) +5). This parameter should always be set to an approximation of what you anticipate your maximum number of concurrent users to be plus the number of processes plus a 10% fudge factor.

SESSION_PRIVS: Data dictionary view providing information on privileges that the user currently has set.

SESSION_ROLES: Data dictionary view providing information on roles that the user currently has enabled.

SESSIONS_PER_USER: Number of concurrent multiple sessions allowed per user.

SET_ROLE: Statement used by a user or an application during a session to change the roles currently enabled for the session. Statement can be issued a number of times; however, the user or application must already have been granted the roles that you name in the SET ROLE statement. The maximum number of roles that can be concurrently enabled by any user or application is limited by the initialization parameter MAX_ENABLED_ROLES.

Shared pool: Memory structure containing shared cursors, stored procedures, control structures, and other structures.

SHARED_POOL_SIZE: The size in bytes of the shared pool.

SHUTDOWN: Stop the database and instance.

SHUTDOWN ABORT: Stop immediately. Don't shut down processes. Don't allow users to finish the current transaction. Requires instance recovery upon next open.

SHUTDOWN IMMEDIATE: Immediately log the connected users off, all uncommitted transactions are rolled back, and shut down the database.

SHUTDOWN NORMAL: Stop the database but wait for all connected users to log off and don't stop other users from connecting.

SHUTDOWN TRANSACTIONAL: Stop, but allow connected users to finish current transaction before Oracle automatically logs them off.

SPFILE

The name of the server parameter file (SPFILE) currently in use. Can be defined in a client-side PFILE to indicate the name of the server parameter file to use. When the default server parameter file is used by the server, the value of SPFILE is internally set by the server.

Also, the server parameter file that provides the instance with static as well as dynamic parameters.

SQL_TRACE: Facility allowing an administrator to see what SQL is being run by an application, even if that administrator has only limited access to the program.

STARTUP: Start the instance and optionally open the database.

STARTUP MOUNT: Start up the instance and mount, but don't open, the database. Used for many maintenance tasks.

STARTUP NOMOUNT: Start the instance but don't access any database. Used for creation of new database.

SARTUP OPEN: Start up the instance and open it for access by all users.

STARTUP RESTRICT: Start up the instance and open the database but only allow connections from those with RESTRICTED_SESSION privilege to connect. Used for many maintenance tasks.

Synonym: Alternative name for a database object. Often used to allow a user to access an object belonging to another user without having to prefix the object name with the owner's username.

System global area (SGA): The memory that Oracle takes when the database is started.

System Monitor (SMON): Background process created when you start the database. Performs instance recovery, cleans up after dirty shutdowns, and coalesces adjacent free extents into larger free extents.

System privileges: Privileges granted to users to allow users to perform particular systemwide actions or a particular action on a particular type of schema object.

SYSTEM tablespace: Tablespace containing the data dictionary.

Table: Primary object used for storing data in a relational database. Contains rows and columns.

Table partition segment: Segment containing a single partition for a partitioned table.

Table segment: Segment allocated to hold table data.

Templates: A predefined file having a preset format used as a starting point for creating a database through DBCA so that the format does not have to be re-created each time it is used and so that subsequent databases can be created similar to existing.

Temporary segment: Segment allocated to contain only temporary data for sorting.

Temporary tablespace: Tablespace defined for holding only temporary data; used for sorting.

Territory support: Support for local cultural conventions specific to geographical locations including the default local time format, date format, and numeric and monetary conventions that depend on the local territory setting.

TRANSACTIONS: Maximum number of concurrent transactions. Increasing the value increases the size of the SGA and can impact the number of rollback segments allocated. Defaults to a number higher than SESSIONS to account for recursive transactions.

TRUNCATE: Remove all data and lower the high water mark.

UNDO: Data used to provide a read-consistent view of the database and to allow transactions to be rolled back.

UNDO_MANAGEMENT: Specifies which method of undo management should be used for the instance. A setting of AUTO makes the instance start in automatic space management mode. A setting of MANUAL makes the instance start in manual mode in which space is allocated externally as rollback segments.

UNDO_RETENTION: Amount in seconds of undo information that should be maintained in the database for automatic undo management. Current UNDO tablespace needs to have sufficient space to ensure that the value for this parameter is possible.

UNDO SEGMENT: Segment used to hold undo information in automatic undo managed database.

UNDO_SUPPRESS_ERRORS: Enables the suppression of errors encountered by commands executing for external (manual) undo processes. ALTER ROLLBACK SEGMENT under automatic undo management would cause an error if this parameter is not set to trUE. The use of this parameter is intended for systems that want to start using automatic undo while not requiring all programs to be changed initially to eliminate these commands.

UNDO_TABLESPACE: Undo tablespace to be used at instance startup for automatic undo management. If a parameter is omitted, the first available undo tablespace is used. If no undo tablespace is available, the instance starts but uses the SYSTEM rollback segments.

user_dump_dest: Specifies the directory where the server writes the debugging trace files on behalf of the user processes.

User processes: User sessions connected to the database.

USER_ views: Displays all the information from the schema of the current user. No special privileges are required to query these views.

User-defined data types: Oracle-provided capability to define custom data types to meet changing business needs.

V$ views: Dynamic performance views located in the data dictionary.

V$CONTROLFILE: Data dictionary view that provides all the names of all the control files in the database.

V$DATABASE: Data dictionary view that provides access to information about the database that is stored in the control file.

V$DATAFILE: Data dictionary view that contains information about each data file based on the information from the control file.

V$LOG: Data dictionary view that contains information about redo logs from the control file.

V$LOGFILE: Data dictionary view that provides the current status of all redo logs in the database.

V$ROLLNAME: Data dictionary view that lists the names of all rollback segments defined in the database.

V$ROLLSTAT: Data dictionary view that provides statistics about each rollback segment.

V$SESSION: Data dictionary view that lists each session in the instance.

V$TABLESPACES: Data dictionary view that provides information about tablespaces, based on information stored in the control file.

V$TEMPFILE: Data dictionary view that provides information about temp files in the database.

V$TRANSACTION: Data dictionary view that lists all the transactions in the system.

V$UNDOSTAT: Data dictionary view that lists a variety of information about the use of undo space by the database.

VALIDATE STRUCTURE: Validates the structure of the analyzed object. If you use when analyzing a cluster, Oracle automatically validates the structure of all the cluster's tables.

View: Tablelike logical structure that presents a predefined query to the end user.