Help Reference of SQL*Plus: Release 9.0.1.0.1

SQL> HELP

 HELP
 ----

 Accesses the SQL*Plus help system.  Enter HELP INDEX for a list of topics.

 HELP [topic]

SQL> HELP INDEX

Enter Help [topic] for help.

 @             COPY         PAUSE                    SHUTDOWN
 @@            DEFINE       PRINT                    SPOOL
 /             DEL          PROMPT                   SQLPLUS
 ACCEPT        DESCRIBE     QUIT                     START
 APPEND        DISCONNECT   RECOVER                  STARTUP
 ARCHIVE LOG   EDIT         REMARK                   STORE
 ATTRIBUTE     EXECUTE      REPFOOTER                TIMING
 BREAK         EXIT         REPHEADER                TTITLE
 BTITLE        GET          RESERVED WORDS (SQL)     UNDEFINE
 CHANGE        HELP         RESERVED WORDS (PL/SQL)  VARIABLE
 CLEAR         HOST         RUN                      WHENEVER OSERROR
 COLUMN        INPUT        SAVE                     WHENEVER SQLERROR
 COMPUTE       LIST         SET
 CONNECT       PASSWORD     SHOW

SQL> HELP @

 @ ("at" sign)
 -------------

 Runs the SQL*Plus statements in the specified command file. The command
 file can be called from the local file system or from a web server.

 @ {uri|file_name[.ext]} [arg...]

 where uri supports HTTP, FTP and gopher protocols in the form:

    http://host.domain/script.sql

 uri is only supported on Windows platforms in this release.

 @@ (double "at" sign)
 ---------------------

 Runs the specified command file. This command is identical to the @
 command. It is useful for running nested command files because it
 looks for the specified command file in the same uri or path as the
 command file from which it was called.

 @@ file_name[.ext] [arg...]

SQL> HELP /

 / (slash)
 ---------

 Executes the SQL command or PL/SQL block in the SQL buffer.
 Use slash (/) at the command prompt or at a line number prompt.

 /

SQL> HELP ACCEPT

 ACCEPT
 ------

 Reads a line of input and stores it in a given user variable.

 ACC[EPT] variable [NUM[BER] | CHAR | DATE] [FOR[MAT] format]
   [DEF[AULT] default] [PROMPT text | NOPR[OMPT]] [HIDE]

SQL> HELP APPEND

 APPEND
 ------

 Adds text to the end of the current line in the SQL
 buffer.

 A[PPEND] text

SQL> HELP  ARCHIVE LOG

 ARCHIVE LOG
 -----------

 Starts or stops automatic archiving of online redo log files,
 manually (explicitly) archives specified redo log files, or displays
 information about redo log files.

 ARCHIVE LOG {LIST|STOP} | {START|NEXT|ALL|integer} [TO destination]

SQL> HELP ATTRIBUTE

 ATTRIBUTE
 ---------

 Specifies display characteristics for a given attribute of
 an Object Type column, such as format for NUMBER data.

 Also lists the current display characteristics for a single
 attribute or all attributes.

 ATTRIBUTE [type_name.attribute_name [option... ]]

 where option is one of the following terms or clauses:
     ALI[AS] alias
     CLE[AR]
     FOR[MAT] format
     LIKE {type_name.attribute_name | alias}
     ON|OFF

SQL> HELP BREAK

 BREAK
 -----

 Specifies where and how to make format changes to a report.

 BRE[AK] [ON report_element [action [action]]] ...

 where report_element has the following syntax:
     {column | expression | ROW | REPORT}

 and where action has the following syntax:
     [SKI[P] n | [SKI[P]] PAGE] [NODUP[LICATES] | DUP[LICATES]]

SQL> HELP CHANGE

 CHANGE
 ------

 Changes the first occurrence of the specified text on
 the current line of the SQL buffer.

 C[HANGE] sepchar old [sepchar [new[sepchar]]]

SQL> HELP CLEAR

 CLEAR
 -----

 Resets or erases the current value or setting for the specified option,

 CL[EAR] option ...

 where option is one of the following clauses:
     BRE[AKS]
     BUFF[ER]
     COL[UMNS]
     COMP[UTES]
     SCR[EEN]
     SQL
     TIMI[NG]

SQL> HELP COLUMN

 COLUMN
 ------

 Specifies display attributes for a given column, such as:
     - column heading text
     - column heading alignment
     - NUMBER data format
     - column data wrapping

 Also lists the current display attributes for a single column
 or all columns.

 COL[UMN] [{column | expr} [option...] ]

 where option is one of the following clauses:
     ALI[AS] alias
     CLE[AR]
     ENTMAP {ON|OFF}
     FOLD_A[FTER]
     FOLD_B[EFORE]
     FOR[MAT] format
     HEA[DING] text
     JUS[TIFY] {L[EFT] | C[ENTER] | C[ENTRE] | R[IGHT]}
     LIKE {expr | alias}
     NEWL[INE]
     NEW_V[ALUE] variable
     NOPRI[NT] | PRI[NT]
     NUL[L] text
     OLD_V[ALUE] variable
     ON|OFF
     WRA[PPED] | WOR[D_WRAPPED] | TRU[NCATED]

SQL> HELP COMPUTE

 COMPUTE
 -------

 Calculates and prints summary lines, using various standard
 computations, on subsets of selected rows. It also lists all
 COMPUTE definitions.

 COMP[UTE] [function [LAB[EL] text] ...
   OF {expr|column|alias} ...
   ON {expr|column|alias|REPORT|ROW} ...]

SQL> HELP CONNECT

 CONNECT
 -------

 Connects a given username to Oracle.

 CONN[ECT] [{logon|/} [AS {SYSOPER|SYSDBA}]]

 where logon has the following syntax:
     username[/password][@connect_identifier]

SQL> HELP COPY

 COPY
 ----

 COPY copies data from a query to a table in a local or remote
 database. COPY supports CHAR, DATE, LONG, NUMBER and VARCHAR2.

 COPY {FROM database | TO database | FROM database TO database}
            {APPEND|CREATE|INSERT|REPLACE} destination_table
            [(column, column, column, ...)] USING query

 where database has the following syntax:
     username[/password]@connect_identifier

SQL> HELP DEFINE

 DEFINE
 ------

 Specifies a user variable and assigns it a CHAR value, or
 lists the value and variable type of a single variable or all
 variables.

 DEF[INE] [variable] | [variable = text]

SQL>
SQL> HELP DEL

 DEL
 ---

 Deletes one or more lines of the SQL buffer.

 DEL [n | n m | n * | n LAST | * | * n | * LAST | LAST]

SQL> HELP DESCRIBE

 DESCRIBE
 --------

 Lists the column definitions for a table, view, or synonym,
 or the specifications for a function or procedure.

 DESC[RIBE] {[schema.]object[@connect_identifier]}

SQL> HELP DISCONNECT

 DISCONNECT
 ----------

 Commits pending changes to the database and logs the current
 user out of Oracle, but does not exit SQL*Plus. Use EXIT or
 QUIT to log out of Oracle and return control to your host
 computer's operating system.

 DISC[ONNECT]

SQL> HELP EDIT

 EDIT
 ----

 Invokes a host operating system text editor on the contents of
 the specified file or on the contents of the SQL buffer.

 ED[IT] [file_name[.ext]]

SQL> HELP EXECUTE

 EXECUTE
 -------

 Executes a single PL/SQL statement or runs a stored procedure.

 EXEC[UTE] statement

SQL> HELP EXIT

 EXIT
 ----

 Terminates SQL*Plus and returns control to the operating
 system.

 {EXIT|QUIT} [SUCCESS|FAILURE|WARNING|n|variable|:BindVariable]
   [COMMIT|ROLLBACK]

SQL> HELP GET

 GET
 ---

 Loads a SQL statement or PL/SQL block from a host operating system
 file into the SQL buffer.

 GET file_name[.ext] [LIS[T] | NOL[IST]]

SQL> HELP HELP

 HELP
 ----

 Accesses the SQL*Plus HELP system.  Enter HELP INDEX for a list of topics.

 HELP [topic]

SQL> HELP HOST

 HOST
 ----

 Executes a host operating system command without leaving
 SQL*Plus.

 HO[ST] [command]

SQL> HELP INPUT

 INPUT
 -----

 Adds one or more lines of text after the current line in the
 SQL buffer.

 I[NPUT] [text]

SQL> HELP LIST

 LIST
 ----

 Lists one or more lines of the SQL buffer. Enter LIST with no
 clauses to list all lines.

 L[IST] [n | n m | n  * | n LAST | * | * n | * LAST | LAST]

SQL> HELP PASSWORD

 PASSWORD
 --------

 Allows you to change a password without echoing the password
 on an input device.

 PASSW[ORD] [username]

SQL> HELP PAUSE

 PAUSE
 -----

 Displays the specified text then waits for the user to press RETURN.

 PAU[SE] [text]

SQL> HELP PRINT

 PRINT
 -----

 Displays the current value of bind variables.

 PRI[NT] [variable ...]

SQL> HELP PROMPT

 PROMPT
 ------

 Sends the specified message or a blank line to the user's
 screen.

 PRO[MPT] [text]

SQL> HELP QUIT

 QUIT
 ----

 Terminates SQL*Plus and returns control to the operating system.

 Enter HELP EXIT for QUIT command syntax.

 

SQL> HELP RECOVER

 RECOVER
 -------

 Performs media recovery on one or more tablespaces, one or more
 datafiles, or the entire database.

 RECOVER {general | managed} | END BACKUP}

 where the general clause has the following syntax:
   [AUTOMATIC] [FROM location]
   { {full_database_recovery  | partial_database_recovery  |LOGFILE filename}
   [ {TEST | ALLOW integer CORRUPTION }
   [TEST | ALLOW integer CORRUPTION]...]
   |CONTINUE [DEFAULT]|CANCEL}

   where the full_database_recovery clause has the following syntax:
     [STANDBY] DATABASE
     [{ UNTIL {CANCEL | TIME date | CHANGE integer}
      | USING BACKUP CONTROLFILE}
      [UNTIL {CANCEL | TIME date | CHANGE integer}
      | USING BACKUP CONTROLFILE]...]

   where the partial_database_recovery clause has the following syntax:
     {TABLESPACE tablespace [, tablespace]...
      | DATAFILE datafilename [, datafilename]...
      | STANDBY
     {TABLESPACE tablespace [, tablespace]...
      | DATAFILE datafilename [, datafilename]...}
     UNTIL [CONSISTENT] [WITH] CONTROLFILE }

 where the managed clause has the following syntax:
   MANAGED STANDBY DATABASE
     [ {NODELAY | [TIMEOUT] integer | CANCEL [IMMEDIATE] [NOWAIT]}
       | [DISCONNECT [FROM SESSION] ] [FINISH [NOWAIT] ] ]

SQL> HELP REMARK

 REMARK
 ------

 Begins a comment in a command file. SQL*Plus does not interpret
 the comment as a command.

 REM[ARK]

SQL> HELP  REPFOOTER

 REPFOOTER
 ---------

 Places and formats a footer at the bottom of a report, or lists the
 REPFOOTER definition.

 REPF[OOTER] [PAGE] [printspec [text|variable] ...] | [OFF|ON]

 where printspec is one or more of the following clauses:
     COL n          LE[FT]        BOLD
     S[KIP] [n]     CE[NTER]      FORMAT text
     TAB n          R[IGHT]

SQL> HELP REPHEADR
SP2-0172: HELP 不可用。
SQL> HELP REPHEADER

 REPHEADER
 ---------

 Places and formats a header at the top of a report, or lists the
 REPHEADER definition.

 REPH[EADER] [PAGE] [printspec [text|variable] ...] | [OFF|ON]

 where printspec is one or more of the following clauses:
     COL n          LE[FT]        BOLD
     S[KIP] [n]     CE[NTER]      FORMAT text
     TAB n          R[IGHT]

SQL> HELP RESERVED WORDS

 RESERVED WORDS (PL/SQL)
 -----------------------

 PL/SQL Reserved Words have special meaning in PL/SQL, and may not be used
 for identifier names (unless enclosed in "quotes").

 An asterisk (*) indicates words are also SQL Reserved Words.

 ALL*            DESC*           JAVA            PARTITION       SUBTYPE
 ALTER*          DISTINCT*       LEVEL*          PCTFREE*        SUCCESSFUL*
 AND*            DO              LIKE*           PLS_INTEGER     SUM
 ANY*            DROP*           LIMITED         POSITIVE        SYNONYM*
 ARRAY           ELSE*           LOCK*           POSITIVEN       SYSDATE*
 AS*             ELSIF           LONG*           PRAGMA          TABLE*
 ASC*            END             LOOP            PRIOR*          THEN*
 AT              EXCEPTION       MAX             PRIVATE         TIME
 AUTHID          EXCLUSIVE*      MIN             PROCEDURE       TIMESTAMP
 AVG             EXECUTE         MINUS*          PUBLIC*         TO*
 BEGIN           EXISTS*         MINUTE          RAISE           TRIGGER*
 BETWEEN*        EXIT            MLSLABEL*       RANGE           TRUE
 BINARY_INTEGER  EXTENDS         MOD             RAW*            TYPE
 BODY            FALSE           MODE*           REAL            UID*
 BOOLEAN         FETCH           MONTH           RECORD          UNION*
 BULK            FLOAT*          NATURAL         REF             UNIQUE*
 BY*             FOR*            NATURALN        RELEASE         UPDATE*
 CHAR*           FORALL          NEW             RETURN          USE
 CHAR_BASE       FROM*           NEXTVAL         REVERSE         USER*
 CHECK*          FUNCTION        NOCOPY          ROLLBACK        VALIDATE*
 CLOSE           GOTO            NOT*            ROW*            VALUES*
 CLUSTER*        GROUP*          NOWAIT*         ROWID*          VARCHAR*
 COLLECT         HAVING*         NULL*           ROWLABEL        VARCHAR2*
 COMMENT*        HEAP            NUMBER*         ROWNUM*         VARIANCE
 COMMIT          HOUR            NUMBER_BASE     ROWTYPE         VIEW*
 COMPRESS*       IF              OCIROWID        SAVEPOINT       WHEN
 CONNECT*        IMMEDIATE*      OF*             SECOND          WHENEVER*
 CONSTANT        IN*             ON*             SELECT*         WHERE*
 CREATE*         INDEX*          OPAQUE          SEPERATE        WHILE
 CURRENT*        INDICATOR       OPEN            SET*            WITH*
 CURRVAL         INSERT*         OPERATOR        SHARE*          WORK
 CURSOR          INTEGER*        OPTION*         SMALLINT*       WRITE
 DATE*           INTERFACE       OR*             SPACE           YEAR
 DAY             INTERSECT*      ORDER*          SQL             ZONE
 DECLARE         INTERVAL        ORGANIZATION    SQLCODE
 DECIMAL*        INTO*           OTHERS          SQLERRM
 DEFAULT*        IS*             OUT             START*
 DELETE*         ISOLATION       PACKAGE         STDDEV

 RESERVED WORDS (SQL)
 --------------------

 SQL Reserved Words have special meaning in SQL, and may not be used for
 identifier names unless enclosed in "quotes".

 An asterisk (*) indicates words are also ANSI Reserved Words.

 Oracle prefixes implicitly generated schema object and subobject names
 with "SYS_". To avoid name resolution conflict, Oracle discourages you
 from prefixing your schema object and subobject names with "SYS_".

 ACCESS          DEFAULT*         INTEGER*        ONLINE          START
 ADD*            DELETE*          INTERSECT*      OPTION*         SUCCESSFUL
 ALL*            DESC*            INTO*           OR*             SYNONYM
 ALTER*          DISTINCT*        IS*             ORDER*          SYSDATE
 AND*            DROP*            LEVEL*          PCTFREE         TABLE*
 ANY*            ELSE*            LIKE*           PRIOR*          THEN*
 AS*             EXCLUSIVE        LOCK            PRIVILEGES*     TO*
 ASC*            EXISTS           LONG            PUBLIC*         TRIGGER
 AUDIT           FILE             MAXEXTENTS      RAW             UID
 BETWEEN*        FLOAT*           MINUS           RENAME          UNION*
 BY*             FOR*             MLSLABEL        RESOURCE        UNIQUE*
 CHAR*           FROM*            MODE            REVOKE*         UPDATE*
 CHECK*          GRANT*           MODIFY          ROW             USER*
 CLUSTER         GROUP*           NOAUDIT         ROWID           VALIDATE
 COLUMN          HAVING*          NOCOMPRESS      ROWNUM          VALUES*
 COMMENT         IDENTIFIED       NOT*            ROWS*           VARCHAR*
 COMPRESS        IMMEDIATE*       NOWAIT          SELECT*         VARCHAR2
 CONNECT*        IN*              NULL*           SESSION*        VIEW*
 CREATE*         INCREMENT        NUMBER          SET*            WHENEVER*
 CURRENT*        INDEX            OF*             SHARE           WHERE
 DATE*           INITIAL          OFFLINE         SIZE*           WITH*
 DECIMAL*        INSERT*          ON*             SMALLINT*

SQL> HELP RUN

 RUN
 ---

 Lists and executes the SQL command or PL/SQL block currently in
 the SQL buffer.

 R[UN]

SQL> HELP  SAVE

 SAVE
 ----

 Saves the contents of the SQL buffer in a host operating system
 command file.

 SAV[E] file_name[.ext] [CRE[ATE] | REP[LACE] | APP[END]]

SQL> HELP SET

 SET
 ---

 Sets a system variable to alter the SQL*Plus environment settings
 for your current session, for example:
     -   display width for NUMBER data
     -   turn on HTML formatting
     -   enabling or disabling printing of column headings
     -   number of lines per page

 SET system_variable value

 where system_variable and value represent one of the following clauses:

   APPI[NFO]{OFF|ON|text}                   NEWP[AGE] {1|n|NONE}
   ARRAY[SIZE] {15|n}                       NULL text
   AUTO[COMMIT] {OFF|ON|IMM[EDIATE]|n}      NUMF[ORMAT] format
   AUTOP[RINT] {OFF|ON}                     NUM[WIDTH] {10|n}
   AUTORECOVERY {ON|OFF}                    PAGES[IZE] {24|n}
   AUTOT[RACE] {OFF|ON|TRACE[ONLY]}         PAU[SE] {OFF|ON|text}
     [EXP[LAIN]] [STAT[ISTICS]]             RECSEP {WR[APPED] |
   BLO[CKTERMINATOR] {.|c}                    EA[CH]|OFF}
   CMDS[EP] {;|c|OFF|ON}                    RECSEPCHAR {_|c}
   COLSEP  {_|text}                         SERVEROUT[PUT] {OFF|ON}
   COM[PATIBILITY] {V7|V8|NATIVE}             [SIZE n] [FOR[MAT]
   CON[CAT] {.|c|OFF|ON}                      {WRA[PPED] |
   COPYC[OMMIT] {0|n}                         WOR[D_WRAPPED] |
   COPYTYPECHECK {OFF|ON}                     TRU[NCATED]}]
   DEF[INE] {'&'|c|OFF|ON}                  SHIFT[INOUT] {VIS[IBLE] |
   DESCRIBE [DEPTH {1|n|ALL}]                 INV[ISIBLE]}
     [LINENUM {ON|OFF}] [INDENT {ON|OFF}]   SHOW[MODE] {OFF|ON}
   ECHO {OFF|ON}                            SQLBL[ANKLINES] {ON|OFF}
   EDITF[ILE] file_name[.ext]               SQLC[ASE] {MIX[ED] |
   EMB[EDDED] {OFF|ON}                        LO[WER] | UP[PER]}
   ESC[APE] {\|c|OFF|ON}                    SQLCO[NTINUE] {> | text}
   FEED[BACK] {6|n|OFF|ON}                  SQLN[UMBER] {OFF|ON}
   FLAGGER {OFF|ENTRY|INTERMED[IATE]|FULL}  SQLPLUSCOMPAT[IBILITY] {x.y[.z]}
   FLU[SH] {OFF|ON}                         SQLPRE[FIX] {#|c}
   HEA[DING] {OFF|ON}                       SQLP[ROMPT] {SQL>|text}
   HEADS[EP] {||c|OFF|ON}                   SQLT[ERMINATOR]
   INSTANCE [instance_path|LOCAL]             {;|c|OFF|ON}
   LIN[ESIZE] {80|n}                        SUF[FIX] {SQL|text}
   LOBOF[FSET] {n|1}                        TAB {OFF|ON}
   LOGSOURCE [pathname]                     TERM[OUT] {OFF|ON}
   LONG {80|n}                              TI[ME] {OFF|ON}
   LONGC[HUNKSIZE] {80|n}                   TIMI[NG] {OFF|ON}
   MARK[UP] HTML [ON|OFF]                   TRIM[OUT] {OFF|ON}
     [HEAD text] [BODY text] [TABLE text]   TRIMS[POOL] {ON|OFF}
     [ENTMAP {ON|OFF}]                      UND[ERLINE] {-|c|ON|OFF}
     [SPOOL {ON|OFF}]                       VER[IFY] {OFF|ON}
     [PRE[FORMAT] {ON|OFF}]                 WRA[P] {OFF|ON}

SQL> HELP SHOW

 SHOW
 ----

 Shows the value of a SQL*Plus system variable, or the
 current SQL*Plus environment.

 SHO[W] option

 where option is one of the following terms or clauses:
     system_variable
     ALL
     BTI[TLE]
     ERR[ORS] [{FUNCTION | PROCEDURE | PACKAGE | PACKAGE BODY | TRIGGER
              | VIEW | TYPE | TYPE BODY | DIMENSION | JAVA CLASS} [schema.]name]
     LNO
     PARAMETERS [parameter_name]
     PNO
     REL[EASE]
     REPF[OOTER]
     REPH[EADER]
     SGA
     SPOO[L]
     SQLCODE
     TT[ITLE]
     USER

SQL> HELP SHUTDOWN

 SHUTDOWN
 --------

 Shuts down a currently running Oracle instance, optionally closing
 and dismounting a database.

 SHUTDOWN [ABORT|IMMEDIATE|NORMAL|TRANSACTIONAL [LOCAL]]

SQL> HELP SPOOL

 SPOOL
 -----

 Stores query results in an operating system file, or sends the
 file to a printer.

 SPO[OL] [file_name[.ext] | OFF | OUT]

SQL> HELP SQLPLUS

 SQLPLUS
 -------

 Starts SQL*Plus from the operating system prompt.

 SQLPLUS [ [option] [logon] [start] ]

 where option has the following syntax:
     -H[ELP] | -V[ERSION]
     | [ [-M[ARKUP] markup_option] [-R[ESTRICT] {1|2|3}] [-S[ILENT]] ]

 and where markup_option has the following syntax:
     HTML [ON|OFF] [HEAD text] [BODY text] [TABLE text]
          [ENTMAP {ON|OFF}] [SPOOL {ON|OFF}] [PRE[FORMAT] {ON|OFF}]

 and where logon has the following syntax:
     {username[/password][@connect_identifier] | /}
     [AS {SYSOPER|SYSDBA}] | /NOLOG

 and where start has the following syntax:
     @filename[.ext] [parameter ...]

SQL> HELP START

 START
 -----

 Runs the SQL*Plus statements in the specified command file.

 STA[RT] {uri|file_name[.ext]} [arg...]

 where uri supports HTTP, FTP and gopher protocols in the form:

    http://host.domain/script.sql

 uri is only supported on Windows platforms in this release.

 STARTUP
 -------

 Starts an Oracle instance with several options, including mounting,
 and opening a database.

 STARTUP [FORCE] [RESTRICT] [PFILE=filename] [MOUNT [dbname]
         | OPEN [open_options] [dbname] | NOMOUNT]

 where open_options has the following syntax:
     READ {ONLY|WRITE [RECOVER]} | RECOVER

SQL> HELP STARTUP

 STARTUP
 -------

 Starts an Oracle instance with several options, including mounting,
 and opening a database.

 STARTUP [FORCE] [RESTRICT] [PFILE=filename] [MOUNT [dbname]
         | OPEN [open_options] [dbname] | NOMOUNT]

 where open_options has the following syntax:
     READ {ONLY|WRITE [RECOVER]} | RECOVER

SQL> HELP STORE

 STORE
 -----

 Saves attributes of the current SQL*Plus environment in a host
 operating system file (a command file).

 STORE {SET} file_name[.ext] [CRE[ATE] | REP[LACE] | APP[END]]

SQL> HELP TIMING

 TIMING
 ------

 Records timing data for an elapsed time period, lists the
 current timer's name and timing data, or lists the number of active
 timers.

 TIMI[NG] [START text|SHOW|STOP]

SQL> HELP TTITLE

 TTITLE
 ------

 Places and formats a title at the top of each report page.
 Enter TTITLE with no clause to list its current definition.

 The old form of TTITLE is used if only a single word or
 a string in quotes follows the TTITLE command.

 TTI[TLE] [printspec [text|variable] ...] | [OFF|ON]

 where printspec is one or more of the following clauses:

     COL n          LE[FT]        BOLD
     S[KIP] [n]     CE[NTER]      FORMAT text
     TAB n          R[IGHT]

SQL> HELP UNDEFINE

 UNDEFINE
 --------

 Deletes one or more user variables that you defined either
 explicitly (with the DEFINE command), or implicitly (with a START
 command argument).

 UNDEF[INE] variable ...

SQL> HELP VARIABLE

 VARIABLE
 --------

 Declares a bind variable that can then be referenced in PL/SQL.
 VARIABLE with no arguments displays a list of all variables declared
 in the session. VARIABLE followed by a name lists that variable.

 VAR[IABLE] [variable [NUMBER | CHAR | CHAR (n [CHAR|BYTE]) | NCHAR
            | NCHAR (n) | VARCHAR2 (n [CHAR|BYTE]) | NVARCHAR2 (n)
            | CLOB | NCLOB | REFCURSOR]]

SQL> HELP WHENEVER OSERROR

 WHENEVER OSERROR
 ----------------

 Exits SQL*Plus if an operating system error (such as a file writing
 error) occurs.

 WHENEVER OSERROR {EXIT [SUCCESS|FAILURE|n|variable|:BindVariable]
                   [COMMIT|ROLLBACK] | CONTINUE [COMMIT|ROLLBACK|NONE]}

SQL> HELP WHENEVER SQLERROR

 WHENEVER SQLERROR
 -----------------

 Exits SQL*Plus if a SQL command or PL/SQL block generates an error.

 WHENEVER SQLERROR {EXIT [SUCCESS|FAILURE|WARNING|n|variable|:BindVariable]
                    [COMMIT|ROLLBACK] | CONTINUE [COMMIT|ROLLBACK|NONE]}