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• ACID - Atomicity, Consistency, Isolation, and Durability. Four characteristics that a relational database must be able to maintain for transactions.

ADDM Automatic Database Diagnostic Monitor. A tool that generates performance-tuning reports based on snapshots in the AWR.

ADR Automatic Diagnostic Repository. Default location for the alert log, trace files, and other information useful for fault finding.

ADRCI The ADR command-line interface.

AES Advanced Encryption Standard. A widely used data encryption method.

AL16UTF16 A Unicode fixed-width 2-byte character set, commonly specified for the NLS character set used for NVARCHAR2, NCHAR, and NCLOB data types.

alias (1) In Oracle SQL, an alternative name for a table, a view, or a set of data used in a query. (2) In Oracle Net, a pointer to a connect string. An alias must be resolved into the address of a listener and the name of a service or instance.

AMM Automatic Memory Management. The technique for allowing Oracle full control over sizing SGA and PGA structures.

ANSI American National Standards Institute. A U.S. body that defines a number of standards relevant to computing.

API Application programming interface. A defined method for manipulating data, typically implemented as a set of PL/SQL procedures in a package.

ARBn Background processes that perform extent movement between disks in an Automatic Storage Management (ASM) disk group.

ASA Automatic Segment Advisor. An Oracle advisory tool that can recommend segments (tables or indexes) that are candidates for segment shrink.

ASCII American Standard Code for Information Interchange. A standard (with many variations) for coding letters and other characters as bytes.

ASH Active Session History. A category of information in the AWR that records details of session activity.

ASM Automatic Storage Management. An LVM provided with the Oracle database.

asmcmd A command-line utility used to query and maintain objects in an ASM disk group.

ASMM Automatic Shared Memory Management. The technique for allowing Oracle full control over sizing SGA structures.

ASSM Automatic Segment Space Management. The method of managing space within segments by use of bitmaps.

attribute One element of a tuple (aka a column).

AWR Automatic Workload Repository. A set of tables in the SYSAUX tablespace, populated with tuning data gathered by the MMON process.

background process A process that is part of the instance that is launched at startup.

bfile A large object data type that is stored as an operating system file. The value in the table column is a pointer to the file.

bind variable A value passed from a user process to a SQL statement at statement execution time.

BLOB Binary large object. A LOB data type for binary data, such as photographs and video clips.

block The units of storage into which datafiles are formatted. The size can be 2KB, 4KB, 8KB, 16KB, 32KB, or 64KB.

BMR Block Media Recovery. An RMAN technique for the restoration and recovery of individual data blocks, rather than complete datafiles.

Cartesian product Sometimes called a cross join. A mathematical term that refers to the set of data created by multiplying the rows from two or more tables.

CDB_xxx views Data dictionary views that include metadata across all containers in a container database. Similar to the corresponding DBA_xxx views but has an additional column CON_ID to identify which container this row applies to.

CDB$ROOT The root container in a multitenant environment. All other pluggable databases share the resources defined in CDB$ROOT.

CET Central European time. A time zone used in much of Europe (though not Great Britain) that is one hour ahead of UTC, with daylight saving time in effect during the summer months.

character set The encoding system for representing data within bytes. Different character sets can store different characters and may not be suitable for all languages. Unicode character sets can store any character.

check constraint A simple rule enforced by the database that restricts the values that can be entered into a column.

checkpoint An event that forces the DBWn to write dirty buffers from the database buffer cache to the datafiles.

CKPT The Checkpoint process. The background process responsible for recording the current redo byte address—the point in time up to which the DBWn has written changed data blocks to disk—and for signaling checkpoints, which forces the DBWn to write changed blocks to disk immediately.

client-server architecture A processing paradigm where the application is divided into client software that interacts with the user and server software that interacts with the data.

CLOB Character large object. A LOB data type for character data, such as text documents, stored in the database character set.

cluster A hardware environment where more than one computer shares access to storage.

cluster segment A segment that can contain one or more tables, denormalized into a single structure.

COALESCE A function that returns the first non-null value from its parameter list. If all its parameters are null, then a null value is returned.

column An element of a row; tables are two-dimensional structures, divided horizontally into rows and vertically into columns.

commit To make a change to data permanent.

common privileges A system or object privilege granted to a common user in a multitenant environment and is therefore in effect for that user in all containers.

common profile A database profile that exists for all current and future pluggable databases in a CDB.

common role A database role that is defined in the root container and therefore propagated to all containers. Common roles must be prefixed (by default) with C## and can be granted “commonly” to a common user in all containers or locally to have effect in only the current container.

common user A user account in a container database (CDB) that exists across all pluggable databases (PDB) in a container database. The same user may have different privileges in each PDB. Non-Oracle-maintained common users must be prefixed with (by default) C##.

complete recovery Following a restore of damaged database files, a complete recovery applies all redo actions to bring the database up to date with no loss of data.

connect identifier An Oracle Net service name.

connect role A preseeded role retained only for backward compatibility.

connect string The database connection details needed to establish a session, namely, the address of the listener and the service or instance name.

consistent backup A backup made while the database is closed.

Consolidated Database Replay An enhancement to Oracle Database Replay to replay individual workloads from multiple non-CDBs and play them back within a single multitenant environment. Using Consolidated Database Replay helps to measure resource requirements for the new CDB.

constraint A mechanism for enforcing that a column value must be unique or may contain only certain values. A primary key constraint specifies that the column must be both unique and not null.

container database A database in a multitenant environment that hosts zero, one, or more pluggable databases (PDBs). It will always host the root container and the seed container.

controlfile The file containing pointers to the rest of the database, critical sequence information, and the RMAN repository.

CPU Central processing unit. The chip that provides the processing capability of a computer, such as an Intel i7 or an Oracle SPARC M7.

CTWR Change Tracking Writer. The optional background process that records the addresses of changed blocks to enable fast incremental backups.

data blocks The units into which datafiles are formatted.

data dictionary The tables owned by SYS in the SYSTEM tablespace that define the database and the objects within it.

data dictionary views Views on the data dictionary tables that let the DBA investigate the state of the database.

Data Guard A facility whereby a copy of the production database is created and updated (possibly in real time) with all changes applied to the production database.

Data Pump A facility for transferring large amounts of data at high speed into, out of, or between databases.

database buffer cache An area of memory in the SGA used for working on blocks copied from datafiles.

database event trigger An Oracle program code block that fires when a specific database event occurs such as startup, shutdown, or some other database-wide event. Database event triggers have been enhanced in Oracle Database 12c to automate the opening of pluggable databases when the root container (CDB) starts up.

database link A connection from one database to another, based on a username and password and a connect string.

Database Replay An Oracle monitoring feature that can help to assess the change in performance on a test system by capturing the workload on a production server and replaying the workload on a test system.

datafile The disk-based structure for storing data.

DBA Database administrator. The person responsible for creating and managing Oracle databases—this could be you.

DBA role A preseeded role provided for backward compatibility that includes all the privileges needed to manage a database, except those needed to start up and shut down.

DBCA The Database Configuration Assistant. A GUI tool for creating, modifying, and dropping instances and databases.

DBID Database identifier. A unique number for every database, visible in the DBID column of the V$DATABASE dynamic performance view.

DBMS Database management system. Often used interchangeably with RDBMS.

DBNEWID A command-line utility (usually nid) that can change the value of the DBID for a database.

DBWn or DBWR The Database Writer. The background process responsible for writing changed blocks from the database buffer cache to the datafiles. An instance may have up to 100 Database Writer processes: DBW0–DBW9, DBWa–DBWz, and BW36–BW99.

DDL Data Definition Language. The subset of SQL commands that change object definitions within the data dictionary: CREATE, ALTER, DROP, and TRUNCATE.

deadlock A situation where two sessions block each other, such that neither can do anything. Deadlocks are detected and resolved automatically.

DECODE A function that implements if-then-else conditional logic by testing two terms for equality and returning the third term if they are equal or, optionally, returning some other term if they are not.

DHCP Dynamic Host Configuration Protocol. The standard for configuring the network characteristics of a computer, such as its IP address, in a changing environment where computers can be moved from one location to another.

DIA0 The diagnosability process that detects hang and deadlock situations.

DIAG The diagnosability process that generates diagnostic dumps.

direct path A method of I/O on datafiles that bypasses the database buffer cache.

directory object An Oracle directory, specifically, an object within the database that points to an operating system directory.

dirty buffer A buffer in the database buffer cache that contains a copy of a data block that has been updated and not yet written back to the datafile.

DML Data Manipulation Language. The SQL commands that change data within the database: INSERT, UPDATE, DELETE, and MERGE.

DMnn Data Pump master process. The process that controls a Data Pump job—one will be launched for each job that is running.

DNS Domain Name System. The TCP mechanism for resolving network names into IP addresses.

domain The set of values an attribute is allowed to take. Terminology: tables have rows, and rows have columns with values. Alternatively, relations have tuples, and tuples have attributes with values taken from their domain.

DSS Decision support system. A database, such as a data warehouse, optimized for running queries rather than OLTP work.

DWnn The Data Pump Worker process. There will be one or more of these launched for each Data Pump job that is running.

Easy Connect A method of establishing a session against a database by specifying the address on the listener and the service name, without using an Oracle Net alias.

EBCDIC Extended Binary Coded Decimal Interchange Code. A standard developed by IBM for coding letters and other characters in bytes.

Enterprise Manager Database Express A lightweight monitoring and query tool for an Oracle database instance on a single server. Replaces Enterprise Manager Database Control in Oracle Database 12c.

environment variable A variable set in the operating system shell that can be used by application software and by shell scripts.

equijoin A join condition using an equality operator.

fact table The central table in a star schema, with columns for values relevant to the row and columns used as foreign keys to the dimension tables.

fast incremental backup An incremental backup that uses a block change tracking file to identify only changed blocks since the last backup.

Fast Recovery Area (previously known as the flash recovery area) A default location for all recovery-related files.

FGA Fine-grained auditing. A facility for tracking user access to data, based on the rows that are seen or manipulated.

Flashback Data Archive A database container object that retains historical data for one or more database objects for a specified retention period.

Flashback Database A flashback feature that recovers the entire database to a point in time in the past using Flashback Database logs.

Flashback Database logs Changed database blocks that are stored in the fast recovery area and used for Flashback Database.

Flashback Drop A flashback feature that makes it easy to recover dropped tables if they are still in a tablespace’s recycle bin.

Flashback Query A flashback feature that enables you to view one or more rows in a table at a time in the past.

Flashback Table A Flashback Query that recovers a single table and its associated objects to a point in time that has passed.

fractured block A database block that is simultaneously being read by an operating system copy command and modified by the DBWR process.

full backup A backup containing all blocks of the files backed up, not only those blocks changed since the last backup.

GMT Greenwich mean time. Now referred to as UTC, this is the time zone of the meridian through Greenwich Observatory in London.

Grid computing An architecture where the delivery of a service to end users is not tied to certain server resources but can be provided from anywhere in a pool of resources.

GUI Graphical user interface. A layer of an application that lets users work with the application through a graphical terminal, such as a PC with a mouse.

HTTP Hypertext Transfer Protocol. The protocol that enables the World Wide Web (both invented at the European Organization for Nuclear Research in 1989); this is a layered protocol that runs over TCP/IP.

HWM High water mark. This is the last block of a segment that has ever been used; blocks above this are part of the segment but are not yet formatted for use.

IBM International Business Machines. A well-known computer hardware, software, and services company.

image copy An RMAN copy of a file.

inconsistent backup A backup made while the database was open.

incremental backup A backup containing only blocks that have been changed since the last backup was made.

INITCAP A function that accepts a string of characters and returns each word in title case.

inner join When equijoins and nonequijoins are performed, rows from the source and target tables are matched. These are referred to as inner joins.

instance recovery The automatic repair of damage caused by a disorderly shutdown of the database.

INSTR A function that returns the positional location of an occurrence of a specified string of characters in a source string.

I/O Input/output. The activity of reading from or writing to disks—often the slowest point of a data processing operation because it’s the slowest piece of hardware when compared with CPU and RAM.

IOT Index organized table. A table type where the rows are stored in the leaf blocks of an index segment.

IP Internet Protocol. Together with the Transmission Control Protocol, IP makes up the de facto standard communication protocol (TCP/IP) used for client-server communication over a network.

IPC Interprocess Communications Protocol. The platform-specific protocol, provided by your OS vendor, used for processes running on the same machine to communicate with each other.

ISO International Standards Organization. A group that defines many standards, including SQL.

JEE Java Enterprise Edition. The standard for developing Java applications.

job A row in a scheduler table that specifies what to do and when to do it. The “what” can be a single SQL statement, a PL/SQL block, a PL/SQL stored procedure, a Java stored procedure, an external procedure, or any executable file stored in the server’s file system.

job chain A database object that contains a named series of programs linked together for a combined objective.

job class A scheduler object that is used to associate one or more jobs with a Resource Manager consumer group and to control logging levels.

join The process of connecting rows in different tables, based on common column values.

JOIN…ON A clause that allows the explicit specification of join columns, regardless of their column names. This provides a flexible joining format.

JOIN…USING A syntax that allows a natural join to be formed on specific columns with shared names.

JVM Java Virtual Machine. The run-time environment needed for running code written in Java. Oracle provides a JVM within the database, and there will be one provided by your operating system.

large pool A memory structure within the SGA used by certain processes, such as principally shared server processes and parallel execution servers.

LAST_DAY A function used to obtain the last day in a month given any valid date item.

LDAP Lightweight Directory Access Protocol. The TCP implementation of the X25 directory standard, used by the Oracle Internet Directory for name resolution, security, and authentication. LDAP is also used by other software vendors, including Microsoft and IBM.

LENGTH A function that computes the number of characters in a string, including spaces and special characters.

level 0 incremental backup A full RMAN backup that can be used as the basis for an incremental backup strategy.

level 1 cumulative incremental backup An RMAN backup of all changed blocks since the last level 0 incremental backup.

level 1 differential incremental backup An RMAN backup of all changed blocks since the last level 0 or level 1 incremental backup.

LGWR The Log Writer. The background process responsible for flushing change vectors from the log buffer in memory to the online redo log files on disk.

library cache A memory structure within the shared pool, used for caching SQL statements parsed into their executable form.

lightweight job A scheduler job that has many of the same characteristics of a standard job, except that a lightweight job is ideal for running many short-duration jobs that run frequently.

LISTAGG A function that returns a string aggregation of column values.

listener The server-side process that listens for database connection requests from user processes and launches server processes to establish sessions.

LOB Large object. A data structure that is too large to store within a table. LOBs (Oracle supports several types) are defined as columns of a table but physically are stored in a separate segment.

local privileges A system or object privilege granted to a local user and is therefore in effect for that user in only a single container.

local profile A database profile that exists only in a single PDB and can be assigned only to local users.

local role A database role that is created in a single PDB and granted to a local user and therefore is available to that user in only one container.

local user A user account that is created and exists only in a pluggable database (PDB). The root container (CDB$ROOT) cannot have local users, only common users.

Locale Builder A graphical tool that can create a customized globalization environment by generating definitions for languages, territories, character sets, and linguistic sorting.

log switch The action of closing one online logfile group and opening another: typically triggered by the LGWR process filling the current group.

logical backup A backup that reads a set of database rows and writes them to a file in the operating system or to another tablespace.

LREG The background process responsible for registering database services with the listener.

LRU Least recently used. LRU lists are used to manage access to data structures, using algorithms that ensure the data that has not been accessed for the longest time is the data that will be overwritten.

LVM Logical volume manager. A layer of software that abstracts the physical storage within your computer from the logical storage visible to an application.

MMAN The Memory Manager background process, which monitors and reassigns memory allocations in the SGA for automatically tunable SGA components.

MML Media management layer. Software that lets RMAN make use of automated tape libraries and other SBT devices.

MMNL Manageability Monitor Light. The background process responsible for flushing ASH data to the AWR if MMON is not doing this with the necessary frequency.

MMON The Manageability Monitor background process, responsible for gathering performance-monitoring information and raising alerts.

MOD The modulus operation, a function that returns the remainder of a division operation.

MONTHS_BETWEEN A function that computes the number of months between two given date parameters.

mounted database A situation where the instance has opened the database controlfile but not the online redo logfiles or the datafiles.

MTBF Mean time between failure. A measure of the average length of running time for a database between unplanned shutdowns.

MTS Multithreaded server. Since release 9i, renamed to shared server. This is the technique whereby a large number of sessions can share a small pool of server processes, rather than requiring one server each.

MTTR Mean time to recover. The average time it takes to make the database available for normal use after a failure.

multiplexing To maintain multiple copies of files.

multitenant architecture An architecture that hosts many logical databases within one larger database instance to more efficiently use server resources such as memory, CPU, and I/O.

namespace A logical grouping of objects within which no two objects may have the same name.

natural join A join performed using the NATURAL JOIN syntax when the source and target tables are implicitly equijoined using all identically named columns.

NCLOB National character large object. A LOB data type for character data, such as text documents, stored in the alternative national database character set.

NLS National language support. The capability of the Oracle database to support many linguistic, geographical, and cultural environments—now usually referred to as globalization.

node A computer attached to a network.

non-CDB A stand-alone database that does not use the multitenant architecture. The non-CDB architecture was the only type of architecture available before release 12.

nonequijoin Performed when the values in the join columns fulfill the join condition based on an inequality expression.

null The absence of a value, indicating that the value is not known, missing, or inapplicable.

NULLIF A function that tests two terms for equality. If they are equal, the function returns null; else it returns the first of the two terms tested.

NVL A function that returns either the original item unchanged or an alternative item if the initial term is null.

NVL2 A function that returns a new if-null item if the original item is null or an alternative if-not-null item if the original term is not null.

OC4J Oracle Containers for Java. The control structure provided by the Oracle Application Server for running Java programs. Still supported but replaced by the WebLogic server.

OCA Oracle Certified Associate. You need to pass two exams to achieve this: one on SQL, the other on basic DB admin.

OCI Oracle Call Interface. An API, published as a set of C libraries, that programmers can use to write user processes that will use an Oracle database.

OCP Oracle Certified Professional. The qualification you are working toward.

OCM Oracle Certified Master. The qualification you are ultimately working toward.

ODBC Open Database Connectivity. A standard developed by Microsoft for communicating with relational databases. Oracle provides an ODBC driver that will allow clients running Microsoft products to connect to an Oracle database.

offline backup A backup made while the database is closed.

OLAP Online analytical processing. Select, intensive work involving running queries against a (usually) large database. Oracle provides OLAP capabilities as an option in addition to the standard query facilities.

OLTP Online transaction processing. A pattern of activity within a database typified by a large number of small, short transactions.

online backup A backup made while the database is open.

online redo log The files to which change vectors are streamed by the LGWR.

ORACLE_BASE The root directory into which Oracle products are installed.

ORACLE_HOME The root directory of any one Oracle product.

Oracle Net Oracle’s proprietary communications protocol, layered on top of an industry-standard protocol.

OS Operating system. Typically, in the Oracle environment this will be a version of Unix (perhaps Linux) or Microsoft Windows.

outer join A join performed when rows, which are not retrieved by an inner join, are included for retrieval.

parallelization Using multiple slave processes managed by a single coordinator process to perform queries or DML operations in parallel across multiple CPUs and I/O channels simultaneously. RMAN backups take advantage of parallelism by allocating multiple channels and improving backup performance by executing partitioned chunks of I/O in parallel.

parse To convert SQL statements into a form suitable for execution.

PDB See pluggable database.

PDB$SEED A read-only pluggable database within a root container (CDB) used as a template to create new PDBs within the CDB.

PFILE A text-based file containing initialization parameters and initial values that are set when an Oracle instance starts.

PGA Program Global Area. The variable-sized block of memory used to maintain the state of a database session. PGAs are private to the session and controlled by the session’s server process.

PL/SQL Procedural Language/Structured Query Language. Oracle’s proprietary programming language, which combines procedural constructs, such as flow control, and user interface capabilities with the ability to call SQL statements.

pluggable database Also known as a PDB or a pluggable container. A logical database that exists within a container database and shares the memory, process slots, and other resources with other logical databases within the CDB but is isolated from all other logical databases in the same container. Pluggable databases can be unplugged (removed) from the container database and plugged back in later to the same or different container.

PMON The Process Monitor. The background process responsible for monitoring the state of users’ sessions against an instance.

primary key The column (or combination of columns) whose values can be used to identify each row in a table.

program A scheduler object that provides a layer of abstraction between the job and the action it will perform; it is created with the DBMS_SCHEDULER.CREATE_PROGRAM procedure.

projection The restriction of columns selected from a table. Using projection, you retrieve only the columns of interest and not every possible column.

RAC Real Application Cluster. Oracle’s clustering technology, which allows several instances in different machines to open the same database for scalability, performance, and fault tolerance.

RAID Redundant array of inexpensive disks. Techniques for enhancing performance or fault tolerance by using a volume manager to present a number of physical disks to the operating system as a single logical disk.

RAM Random access memory. The chips that make up the real memory in your computer hardware, as opposed to the virtual memory presented to software by the operating system.

raw device An unformatted disk or disk partition.

RBAL Rebalance process. A background process in an Automatic Storage Management (ASM) instance that coordinates disk activity for disk groups. In an RDBMS instance, it performs the opening and closing of the disks in the disk group.

RDBMS Relational database management system. Often used interchangeably with DBMS.

recovery catalog Objects in a database schema that contain metadata and other backup information for RMAN backups of one or more databases.

recovery window An RMAN parameter and time period that defines how far back in time the database can be recovered.

referential integrity A rule defined on a table specifying that the values in a column (or columns) must map onto those of a row in another table.

relation A two-dimensional structure consisting of tuples with attributes (aka a table).

REPLACE A function that substitutes each occurrence of a search item in the source string with a replacement term and returns the modified source string.

resource consumer groups Groups of users or sessions that have similar resource needs.

Resource Manager An Oracle feature that can allocate resources based on CPU usage, degree of parallelism, number of active sessions, undo space, CPU time limit, and idle time limit.

resource plan A set of rules in Resource Manager that assign various resources at specific percentages or relative priorities to a resource group.

resource plan directives Rules within Resource Manager that associate consumer groups with a resource plan and specify how the resources are divided among the consumer groups or subplans.

restore point A database object containing either a system change number (SCN) or a time in the past used to recover the database to the SCN or timestamp.

resumable space allocation An Oracle feature that suspends instead of terminating large database operations that require more disk space than is currently available. A suspended operation can be restarted from where it finished off at a later point in time, when the space issues have been resolved. It saves time.

retention policy The number of copies of all objects that RMAN will retain for recovery purposes.

RMAN Recovery Manager. Oracle’s backup and recovery tool.

root container The control structure (named CDB$ROOT) in a container database that hosts pluggable databases. All initialization parameters are set in the root container and are inherited by each pluggable database unless overridden. Only a smaller subset of parameters defined in the root container can be changed in a pluggable database along with the default temporary tablespace.

rowid The unique identifier of every row in the database, used as a pointer to the physical location of the row.

RVWR The Recovery Writer background process. An optional process responsible for flushing the flashback buffer to the flashback logs.

SBT System backup to tape. An RMAN term for a tape device.

schema The objects owned by a database user.

SCN System change number. The continually incrementing number used to track the sequence and exact time of all events within a database.

seed container Also known as the seed database in a multitenant environment. The seed container is a special instance of a pluggable database named PDB$SEED, is always read-only, and is used as a template for creating a new pluggable database in the current root container.

segment A database object within a schema that contains a data object (such as a table or index).

segment shrink A database operation that makes the free space in a segment available to other segments in the tablespace by compacting and releasing the empty, unused data blocks in a segment.

selection The extraction of rows from a table. Selection includes the further restriction of the extracted rows based on various criteria or conditions. This allows you to retrieve only the rows that are of interest and not every row in the table.

self-join A join required when the join columns originate from the same table. Conceptually, the source table is duplicated, and a target table is created. The self-join then works as a regular join between two discrete tables.

sequence A database object within a schema that generates unique numbers.

service name A logical name registered by an instance with a listener, which can be specified by a user process when it issues a connect request.

session A user process and a server process, connected to the instance.

SGA System Global Area. The block of shared memory that contains the memory structures that make up an Oracle instance.

share A portion of resources granted to a single PDB. Each PDB will have at least one share, and the total resources available to a PDB are based on the ratio of the PDB’s shares to the total number of shares allocated to all PDBs within a CDB.

shared object An object created in the root container that is available to all current and new PDBs in the container. Only Oracle-supplied common users (such as SYS and SYSTEM) can create shared objects.

SID System identifier. The name of an instance, which must be unique on the computer the instance is running on.

Alternatively, session identifier. The number used to identify uniquely a session logged on to an Oracle instance.

SMON The System Monitor. The background process responsible for opening a database and monitoring the instance.

spfile The server parameter file, which contains the parameters used to build an instance in memory.

SQL Structured Query Language. An international standard language for extracting data from and manipulating data in relational databases.

SQL Tuning Advisor An Oracle advisor that performs statistics analysis, SQL Profile analysis, access path analysis, and structure analysis.

SSL Secure Sockets Layer. A standard for securing data transmission using encryption, checksumming, and digital certificates.

STDDEV A function that returns the square root of the variance.

SUBSTR A function that extracts and returns a segment from a given source string.

SUM A function that returns an aggregated total of all the non-null numeric expression values in a group.

synonym An alternative name for a database object.

SYSASM A system privilege in an ASM instance that facilitates the separation of database administration and storage administration.

sysdba The privilege that lets a user connect with operating system or password file authentication and create or start up and shut down a database.

SYSDG System privilege for Data Guard operations.

SYSKM System privilege for managing Transparent Data Encryption (TDE) keystore operations.

sysoper The privilege that lets a user connect with operating system or password file authentication and start up and shut down (but not create) a database.

system A preseeded schema used for database administration purposes.

table A logical two-dimensional data storage structure, consisting of rows and columns.

tablespace The logical structure that abstracts logical data storage in tables from physical data storage in datafiles.

TCP Transmission Control Protocol. Together with the Internet Protocol, TCP makes up the de facto standard communication protocol (TCP/IP) used for client-server communication over a network.

TCPS TCP with SSL. The secure sockets version of TCP.

tempfile The physical storage that makes up a temporary tablespace, used for storing temporary segments.

TNS Transparent Network Substrate. The heart of Oracle Net, TNS is a proprietary layered protocol running on top of whatever underlying network transport protocol you choose to use—probably TCP/IP.

TO_CHAR A function that performs date-to-character and number-to-character data type conversions.

TO_DATE A function that explicitly transforms character items into date values.

TO_NUMBER A function that changes character items into number values.

transaction A logical unit of work, which will complete in total or not at all.

TSPITR Tablespace point-in-time recovery. A recovery method that is ideal for recovering a set of objects isolated to a single tablespace.

tuple A one-dimensional structure consisting of attributes (in other words, a row).

UGA User Global Area. The part of the PGA stored in the SGA for sessions running through shared servers.

UI User interface. The layer of an application that communicates with end users; nowadays it is frequently graphical: a GUI.

URL Uniform resource locator. A standard for specifying the location of an object on the Internet, consisting of a protocol, a hostname and domain, an IP port number, a path and filename, and a series of parameters.

user-managed recovery Using tools or commands outside of RMAN to recover a database or tablespace.

UTC Coordinated Universal Time, previously known as Greenwich mean time (GMT). UTC is the global standard time zone; all others relate to it as offsets, ahead or behind.

VARIANCE A function that returns the distance from the mean of each number in the set.

virtual private catalog A logical partitioning of an RMAN catalog to facilitate the separation of duties among several DBAs.

whole-database backup A database backup that includes all datafiles plus the controlfile.

window A scheduler construct that extends the concept of schedules by giving Oracle more freedom on deciding when to run a job within a specific start and begin time—for a single day or every day of the week.

X As in X-Windows, the standard GUI environment used on most computers—except those that run Microsoft Windows instead.

XML Extensible Markup Language. A standard for data interchange using documents, where the format of the data is defined by tags within the document.

Fair Use Sources:

• ASIN (OCA1Z0061 2014)