Creates a database file, specifies its name, and determines its
 physical characteristics.  This statement also creates a directory in
 the data dictionary where definitions of other database elements can
 be stored.

 Example (single-file database):

     RDO> DEFINE DATABASE 'PERSONNEL'.

Additional information available:

MoreFormatExamples

 By using the RDBVMS$CREATE_DB logical name and the RDBVMS$CREATE_DB
 identifier, you can restrict the ability of users to create databases
 on your system.  For more information on the RDBVMS$CREATE_DB logical
 name and identifier, see the chapter on defining database protection
 in the VAX Rdb/VMS Guide to Database Design and Definition manual.

 If your system does not use the RDBVMS$CREATE_DB logical name and
 identifier, all users on the system have the ability to create
 databases.

 When the DEFINE DATABASE statement executes, Rdb/VMS:

  o  Creates a database file, a snapshot file, and, if the database is
     multifile, storage area files.
  o  Creates a data dictionary entity for the database, including all
     the system fields and relations, if the dictionary is installed.
  o  Assigns database parameters, and, if the database is multifile,
     storage area parameters.
  o  Creates a default access control list.
  o  Invokes the newly created database, using the database file name
     as the database handle.

 You cannot issue the DEFINE DATABASE statement when a transaction is
 active.  Do not issue an INVOKE DATABASE statement after you use
 DEFINE DATABASE.  Rdb/VMS automatically invokes the database after
 creating the database file.

 Other users are not allowed to be attached to the database when you
 issue the DEFINE DATABASE statement.

 DEFINE DATABASE ──> file-spec ──┬───────────>────────┬─┐
                                 └─> invoke-options ──┘ │
 ┌───────────────────────────<──────────────────────────┘
 └─┬─┬───────────>────────────┬─┬─┬────────────>────────────┬──┐
   │ ├──> db-wide-options-1  ─┤ │ └─> storage-area-options ─┘  │
   │ └──> db-wide-options-2 ──┘ │                              │
   └───────────<────────────────┘                              │
 ┌─────────────────────────────<───────────────────────────────┘
 └┬┬──────────────>──────────────────────────────>───────────┬─┬─> .
  │├─> define-storage-area-clause ────────────────>──────────┤ │
  │└─> 
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  └───────────────────────────────<────────────────────────────┘

Additional information available:

SEGMENTED_STRING

file-specinvoke-optionsdb-wide-options-1db-wide-options-2
storage-area-optionsdefine-storage-area-clause

 A file specification that names the database file.  You should use
 either a full file specification, including device, directory, and
 file name without the file type, or a simple file name.  In the
 second case, Rdb/VMS creates the database in the current default
 directory.  In a single-file database, the file name specified
 becomes the file name for two files:

  o  The database file.  The default file type is RDB.

  o  The snapshot file.  This file is used as a temporary file for
     read-only transactions.  The default file type is SNP.


 Type the name of the file-spec in uppercase letters when you define
 your database if you use the CDD/Plus data dictionary or may use it
 in the future.  If you type the name of the file-spec in lowercase
 letters and try to use the DEFINE GENERIC command of the dictionary's
 CDO utility to create a directory name for the database in the
 dictionary, the command will fail.

 In a multifile database, the file name specified becomes the file
 name for three files:

  o  The database root file.  The default file type is RDB.

  o  The default storage area file.  The default file type is RDA.

  o  A snapshot file.  The default file type is SNP.

 invoke-options =

 ──┬───────────────────────────>──────────────────┬─────────────────>
   ├─────> 
D
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   └─────> 
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                            └──> 
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Additional information available:

COMMITFINISH

db-handle

 The name of the variable you will use to refer to the database.  Do
 not use a file name for the db-handle.

 When the DBKEY SCOPE IS COMMIT clause is specified with a DEFINE
 DATABASE statement, this means that the database key (dbkey) of each
 record used is guaranteed not to change during each transaction.
 That is, if a record is erased, its dbkey is guaranteed not to be
 reused by another database user until after a COMMIT statement is
 executed.

 When the DBKEY SCOPE IS FINISH clause is specified with a DEFINE
 DATABASE statement, this means that the database key (dbkey) of each
 record used is guaranteed not to change until the user detaches from
 the database (usually, by using the FINISH statement).

 db-wide-options-1 =

 ──┬─> 
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   ├─> 
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   │  ┌──────────────────────────────────────┘                │
   │  └─┬───────────────────────────────────┬──> ncs-name ──┐ │
   │    └─> 
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   │    ┌───────────────────────────────────────────────────┘ │
   │    └─┬───────────────────────┬───────────────────────────┤
   │      └─> 
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   ├─> 
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   ├─> 
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   ├─> 
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   ├─> 
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   ├─> 
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S typebox (I)typebox (S) ───> recovery-buffers ───┤
   └─> global-buffer-params ──────────────────────────────────┘

Additional information available:

COLLATING_SEQUENCE

path-namencs-nametextlibrary-namenumber-usersnumber-buffers
number-nodesrecovery-buffersglobal-buffer-params

 The data dictionary path name for the dictionary path name where the
 database definition is stored.  Use this qualifier to store the data
 dictionary definitions for the database in a data dictionary entity
 other than the default path, which is defined by the name of the
 database file.

 Specifies a collating sequence to be used for all fields in the
 database.  Sequence-name is a name of your choosing; use this
 sequence-name in any subsequent statements that refer to this
 collating sequence.

 The VMS National Character Set (NCS) Utility provides a set of
 pre-defined collating sequences and also lets you define collating
 sequences of your own.  The COLLATING_SEQUENCE clause accepts both
 pre-defined and user-defined NCS collating sequences.

 If you do not specify a collating sequence, the default is ASCII
 (shown as "no collating sequence" in some displays).

 Specifies the name of a collating sequence in the default NCS
 library, SYS$LIBRARY:NCS$LIBRARY, or in the NCS library specified by
 the argument library-name.  (In most cases, it is probably simplest
 to make the sequence-name the same as the ncs-name:  for example,
 COLLATING_SEQUENCE IS FRENCH FRENCH.) You can view the collating
 sequence names by using the command NCS/LIST at DCL level.

 The collating sequence can be either one of the pre-defined NCS
 collating sequences or one that you have defined yourself using NCS.

 Provides a comment for a collating sequence or database being
 defined.

 Specifies the name of an NCS library other than the default.  The
 default NCS library is SYS$LIBRARY:NCS$LIBRARY.

 The maximum number of users allowed to access the database at one
 time.  The default is 50 users.  The largest number of users you can
 specify is 2032, and the fewest number of users is 1.

 The number of buffers Rdb/VMS allocates per process using this
 database.  Specify an unsigned integer between 2 and 32768.  The
 default is 20 buffers.

 Sets the upper limit on the maximum number of VAXcluster nodes from
 which users can access the shared database.  The default is 16 nodes.
 The range is 1 node to 96 nodes.  The actual maximum limit is the
 current VMS VAXcluster limit.

 In some cases, after you have specified a particular number of users
 and nodes, doing a dump of the database root file will display a
 different number of nodes than the value you set.  The following
 paragraphs explain why this occurs.

 The relationship between the number of users and the number of nodes
 supported on a database can be seen when you specify 2032 users and 4
 nodes in a SQL CREATE/ALTER DATABASE or RDO DEFINE/CHANGE DATABASE
 statement and then dump the database root file.  The dump displays
 values of 2032 users and 41 nodes.

 To understand this relationship, Rdb/VMS uses a data structure called
 a TSN Block (TSNBLK).  A TSN Block keeps track of transaction
 activity on a node and transaction information for each user on a
 particular node.  Each TSN Block is owned by a particular node and
 can handle up to 50 users.  For each group of 50 users one TSNBLK is
 allocated per node to cover the maximum number of users and
 VAXclusters nodes the database is expected to support, which is
 determined as either one TSNBLK per VAXcluster node, or one TSNBLK
 per 50 users, whichever is larger.  The maximum number of TSN blocks
 is equal to the value of the current maximum number of VAX nodes that
 are supported for a database (currently 96) for Rdb/VMS V4.1.

 For example, if the DBA specifies 2032 users and 4 nodes, this is
 calculated as 2032/50 for a total of 41 TSNBLKs and this equates to
 41 nodes.  The algorithm selects the maximum value of (number of
 nodes specified, number of nodes calculated).  So in this example, 41
 is the maximum calculated value (calculated 41 > specified 4).

 Had the DBA specified 2032 users and 50 nodes, 50 would be the
 maximum value for the number of nodes (specified 50 > calculated 41)
 and 50 TSNBLKs would be allocated, one for each node.

 As another example, if the DBA specifies 50 users and 10 nodes, the
 maximum value is 10 nodes (specified 10 > calculated 1), so ten
 TSNBLKs would be allocated, one for each node.

 The number of database buffers used during the automatic recovery
 process that is initiated after a system or process failure.  This
 recovery process uses the recovery-unit journal file.  Specify an
 unsigned integer between 2 and 32768.  The default is 20 buffers.

 global-buffer-params=

 ─> 
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                        └─> 
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 ┌─────────────────────<────────────────┘
 └─┬────────────────────────>───────────────────────┬──>
   └─> ( ──> 
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R typebox (I)typebox (S) number-glo-buffers ──> , ─┐  │
       ┌───────────────<─────────────────────────┘  │
       └─> 
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Additional information available:

GLOBAL_BUFFERSNUMBERUSER_LIMIT

 The GLOBAL BUFFERS ARE ENABLED clause specifies that Rdb/VMS maintain
 one global buffer pool per VAXcluster node for each database.  By
 default, Rdb/VMS maintains a local buffer pool for each user.  For
 more than one user to use the same page, each must read it from disk
 into their local buffer pool.  When the GLOBAL BUFFERS ARE ENABLED
 clause has been specified, a page in the global buffer pool may be
 read by more than one user at the same time, although only one user
 reads the page from disk into the global buffer pool.  Global
 buffering provides improved performance because I/O is reduced and
 memory is better utilized.

 The default is GLOBAL BUFFERS ARE DISABLED, in which Rdb/VMS
 maintains a local buffer pool for each user, and global buffers are
 not enabled.

 When global buffers are enabled, the NUMBER IS clause is used to
 specify the default number of global buffers per node.

 In database parameter syntax, a user designates an attach to the
 database, not a person who uses the database.

 The default number of global buffers is the maximum number of users
 multiplied by 5.  (In the RDO syntax for database parameters, a user
 is the same as an attach.) You can override the default by defining a
 value for the logical name RDM$BIND_BUFFERS.

 Although you can change the NUMBER IS parameter online, the change
 will only take effect the next time that the database is opened.  By
 default, a database can be opened automatically (that is, by any user
 who invokes the database and executes a data manipulation language
 statement).  If the database was modified so that it must be manually
 opened, the RMU/OPEN command must be used to open it.

 The USER LIMIT clause specifies the maximum number of global buffers
 each user allocates.  Because global buffer pools are shared by all
 users, you must define an upper limit on how many global buffers a
 single user can allocate.  This limit prevents a user from defining
 the RDM$BIND_BUFFERS to use all the buffers in the global buffer
 pool.  The user limit cannot be greater then the total number of
 global buffers.  The default is 5.

 See the VAX Rdb/VMS Guide to Database Performance and Tuning for
 information on determining the maximum number of global buffers a
 user can allocate.

 Although you can change the USER LIMIT IS parameter online, the
 change will only take effect the next time that the database is
 opened.  By default, a database can be opened automatically (that is,
 by any user who invokes the database and executes a data manipulation
 language statement).  If the database was modified so that it must be
 manually opened, the RMU/OPEN command must be used to open it.

 db-wide-options-2 =

 ─┬─> 
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  ├─> 
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  │                                   └───> 
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  ├─> 
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  │                   │                └──> 
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  │                    ├───> 
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  │                    ├───> 
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  │                    └───> 
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  ├─> 
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  │                          └─> 
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Additional information available:

ADJUSTABLE_LOCKENABLED-IMMEDIATEENABLED-DEFERREDDISABLED
DICTIONARYCARRY_OVER_LOCKSLOCK_TIMEOUT

buffer-blocks

 The number of blocks Rdb/VMS allocates per buffer.  Specify an
 unsigned integer greater than zero.  If you do not specify this
 parameter, Rdb/VMS uses a buffer size that is three times the PAGE
 SIZE value.

 Buffer size is a global parameter and the number of blocks per page
 (or buffer) is constrained to less than 64 blocks per page.  The page
 size can vary by storage area for multifile databases, so you should
 determine the page size of each storage area based on the sizes of
 records that will be stored in each storage area.

 When you choose the number of blocks per buffer, choose a number that
 is wholly divisible by all page sizes for all storage areas in your
 multifile database.  For example, if your database has three storage
 areas with page sizes of 2, 3, and 4 blocks respectively, choosing a
 buffer size of 12 blocks will ensure optimal buffer utilization.  If
 you choose a buffer size of 8, the storage area with a page size of 3
 blocks will waste 2 blocks per buffer.  Rdb/VMS reads as many pages
 as will fit into the buffer.  In this case, Rdb/VMS reads two pages
 of 3 blocks apiece into the buffer, wasting 2 blocks.

 Enables or disables whether or not the database system will
 automatically maintain as few locks as possible on database
 resources.  The default is ENABLED, and results in fewer locks
 against the database.  However, if contention for database resources
 is high, the automatic adjustment of locks can become a CPU drain.
 Such databases can trade more restrictive locking for less CPU usage
 by disabling adjustable lock granularity.

 Disabling adjustable locking granularity may require that the
 LOCKIDTBL, LOCKIDTBL_MAX, PQL_DENQLM, PQL_MENQLM VMS SYSGEN
 parameters for locks be increased.

 The default, ENABLED IMMEDIATE causes read/write transactions to
 write copies of records to the the snapshot file before those records
 are modified, regardless of whether a read-only transaction is
 active.

 If you use the SNAPSHOT IS ENABLED clause to enable snapshots on a
 multifile database, writing to all snapshot files for all storage
 areas is enabled.

 Specifies that read/write transactions not write copies of records
 they modify to the snapshot file unless a read-only transaction is
 active.  Read-only transactions that attempt to start after an active
 read/write transaction begins must wait for all active read/write
 users to complete their transactions.

 If you use the SNAPSHOT IS ENABLED clause to enable snapshots on a
 multifile database, writing to all snapshot files for all storage
 areas is enabled.

 Disables snapshot transactions.  If you use the SNAPSHOT IS DISABLED
 clause to disable snapshots on a multifile database, writing to all
 snapshot files for all storage areas is disabled.

 The DICTIONARY IS [NOT] REQUIRED clause determines whether the
 database must be invoked by path name for data definition changes to
 occur.  If you specify the DICTIONARY IS REQUIRED option, the
 database must be invoked by path name to change metadata and the data
 dictionary will be maintained.  If you specify the DICTIONARY IS NOT
 REQUIRED option, the database can be invoked by either file name or
 path name to change metadata.  The default is DICTIONARY IS NOT
 REQUIRED.

 The DICTIONARY IS [NOT] USED clause determines whether the definition
 of the database and definitions of database elements will be stored
 in the data dictionary.  If you specify the DICTIONARY IS USED
 option, the definition of the database and definitions of database
 elements will be stored in the data dictionary.  If you specify the
 DICTIONARY IS NOT USED option, no definitions will be stored in the
 data dictionary.  The default is DICTIONARY IS USED.

 You receive an error message if you specify incompatible options,
 such as the DICTIONARY IS REQUIRED option and the DICTIONARY IS NOT
 USED option.

 The carry-over locks option is a database-wide parameter that allows
 you to disable carry-over lock optimization.  This optimization
 (implemented in Rdb/VMS Version 4.0) is enabled by default.  Although
 this is an advantage in more environments, it can result in false
 lock conflicts in some applications.

 The carry-over locks optimization holds area and record locks across
 transactions and depends on NOWAIT transactions asking for and
 acquiring the NOWAIT lock.  This can result in long delays if
 concurrent users are executing long verbs.  You should consider
 disabling the carry-over locks optimization if transactions
 experience noticeable delays in acquiring the NOWAIT lock (as seen in
 the output of the RMU/SHOW STATISTICS command).  Note that if you do
 disable the carry-over locks option, there may be some performance
 degradation because transactions will acquire and release area and
 top level ALG locks for every transaction.

 Specifies the number of seconds for processes to wait during a lock
 conflict before timing out.  The number of seconds can be between one
 and 65,000.

 Sets the default database lock timeout interval.  This is the
 database wide timeout interval.  It is used as the default as well as
 the upper limit in determining the timeout interval to use.  For
 example, if LOCK TIMEOUT INTERVAL IS 25 SECONDS is specified with the
 CHANGE DATABASE or DEFINE DATABASE statement, and a user specifies 30
 seconds with the SQL SET TRANSACTION WAIT 30 statement or sets the
 logical name RDM$BIND_LOCK_TIMEOUT_INTERVAL to 30, RDO would still
 use the interval of 25 specified with the LOCK TIMEOUT INTERVAL
 clause.

 storage-area-options =

 ─┬┬───────────────────────────>─────────────────────────────────┬┬─>
  │├──> 
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  │├──> 
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  │├──> 
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S typebox (A)typebox (R)typebox (E) ─> ( ─> val1 ┬────────────────────┬─> ) ──┤│
  ││                                └> ,val2 ┬─────────┬─┘       ││
  ││                                         └> ,val3 ─┘         ││
  │├──> 
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  │├──> 
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  │├──> 
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  │├┬─> 
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  ││└─> 
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  │└──> 
W
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  └────────────────────────────<──────────────────────────────────┘

Additional information available:

PAGE_FORMATTHRESHOLDSWRITE_ONCE

number-pagespage-blocksnumber-data-pagesfile-specsnp-pages
extent-pagesextension-options

 The number of database pages allocated to the database initially.
 Rdb/VMS automatically extends the allocation to handle the loading of
 data and subsequent expansion.  The default is 400 pages.

 The size in blocks of each database page.  Page size is allocated in
 512-byte blocks.  The default is two blocks (1024 bytes).  If your
 largest record is larger than approximately 950 bytes, allocate more
 blocks per page to prevent records from being fragmented.

 Specifies whether a storage area contains uniform or mixed pages.
 You can use the PAGE FORMAT option with multifile databases only.  In
 storage areas with uniform page format, all pages in a specific
 logical area contain records from the same relation.  In storage
 areas with mixed page format, pages can hold records from different
 relations.  The default is UNIFORM.

 Specifies one, two, or three threshold values.  The threshold values
 represent a fullness percentage on a data page and establish four
 possible ranges of guaranteed free space on the data pages.  When a
 data page reaches the percentage defined by a given threshold value,
 the SPAM entry for the data page is updated to reflect the new
 fullness percentage and its remaining free space.

 The default thresholds are 70, 85, and 95 percent.  When
 THRESHOLDS ARE is used, the first threshold value is required.  If
 you specify only one or two values, unspecified values default to 100
 percent.  You can specify the THRESHOLDS option only on a storage
 area for a multifile database.  The storage area page format must be
 MIXED.

 Specifies the number of data pages between SPAM pages in the physical
 storage area file, and thus the maximum of data pages each SPAM page
 will manage.  The default, and also the minimum interval, is 256 data
 pages.  The first page of each storage area is a SPAM page.  The
 interval you specify determines where subsequent SPAM pages are to be
 inserted, provided there are enough data pages in the storage file to
 require more SPAM pages.

 You can specify the INTERVAL option only on a storage area for a
 multifile database.  The storage area page format must be MIXED.

 Provides a separate file specification for the snapshot file.  Do not
 specify a file extension other than SNP to the file specification.
 You cannot specify a global default for the SNAPSHOT_FILENAME.  Thus,
 in a multifile database, the SNAPSHOT_FILENAME option must be within
 a DEFINE STORAGE AREA definition.

 The SNAPSHOT_FILENAME option cannot be specified for a single-file
 database.

 Specifies the number of pages allocated for the snapshot file.  The
 default is 100 pages.

 Specifies the number of pages of each extent.  The default is 100
 pages.

 Specifies the MIN, MAX, and percent growth of each database file
 extent.  Enclose the parameter list in parentheses.

 extension-options =

 ───>  (   ───>  
M
I
N
I
M
U
M typebox (O)F ──> min-pages ───> typebox (P)typebox (A)typebox (G)typebox (E)typebox (S), ─┐
              ┌────────────────────────────────────────┘
              └──> 
M
A
X
I
M
U
M typebox (O)F ──> max-pages ──> typebox (P)typebox (A)typebox (G)typebox (E)typebox (S),─┐
              ┌────────────────────────────────────────┘
              └──> 
P
E
R
C
E
N
T 
G
R
O
W
T
H typebox (I)typebox (S) ───> growth ────>   )  ───>

Additional information available:

min-pagesmax-pagesgrowth

 Specifies the minimum number of pages of each extent.  The default is
 99 pages.

 Specifies the maximum number of pages of each extent.  The default is
 9,999 pages.

 Specifies the percent growth of each extent.  The default is 20
 percent growth.

 You can use the WRITE_ONCE option to change a storage area containing
 stable segmented string data to a format that can be stored on a
 write-once, read-many (WORM) optical disk.  A WORM optical disk
 offers a relatively inexpensive way of storing large amounts of data
 for read-only access compared to other storage media.

 The following restrictions apply to the WRITE_ONCE option:

  o  Note that you cannot write data other than segmented strings to a
     write-once storage area.  Rdb/VMS issues an error message if you
     try to create a storage map that stores data other than segmented
     strings in a write-once storage area.  Storage maps for
     non-segmented-string data must be removed before you can alter a
     storage area to WRITE_ONCE.

  o  When you create a storage area on WORM media, you must specify
     that the snapshot area remains on read/write media:  do not give
     a snapshot file the WRITE_ONCE attribute.

  o  If you specify the WRITE_ONCE option when storing a segmented
     string, database keys are not compressed.  For more information
     on database key compression, see the VAX Rdb/VMS Guide to
     Database Maintenance.

  o  Write-once storage areas do not use SPAM pages to look for
     storage space, but to assist moving data back to non-WORM media
     in which SPAM pages must be built again, space is still allocated
     for them.  Since SPAM pages are essential in uniform areas,
     Write-once storage areas cannot be of uniform format and
     therefore are required to be of mixed format.

  o  You can use the PAGE SIZE IS clause of CREATE STORAGE AREA to
     change the default page size for a storage area.  You should
     specify an even number of blocks per page.  The smallest amount
     of space used in a write operation to WORM media is 1024 bytes (2
     blocks).  Therefore, by specifying an even number of blocks per
     page, you minimize the space wasted when writing segmented
     strings to WORM media.

  o  Digital does not support magnetic media for storing write-once
     storage areas.

  o  After you move a storage area to or from a WORM device, Digital
     recommends that you do a full and complete backup of your
     database with the RMU/BACKUP command and start a new after-image
     journaling file.  For more information on backup and recovery
     procedures with write-once storage areas, see the VAX Rdb/VMS
     Guide to Database Maintenance.

 define-storage-area-clause =

 ────> 
D
E
F
I
N
E 
S
T
O
R
A
G
E 
A
R
E
A ──┬────> storage-area-name ────┬──────┐
                             └────> typebox (R)typebox (D)typebox (B)typebox ($)typebox (S)typebox (Y)typebox (S)typebox (T)typebox (E)typebox (M) ───────────┘      │
 ┌────────────────────────────────<──────────────────────────────┘
 └─────> 
F
I
L
E
N
A
M
E ─────> file-spec ──┬────────────>─────────────┬───┐
                                     └─> storage-area-options ──┘   │
 ┌──────────────────────────────────<───────────────────────────────┘
 └─────> 
E
N
D ───────┬──────────>───────────┬─> typebox (S)typebox (T)typebox (O)typebox (R)typebox (A)typebox (G)typebox (E) typebox (A)typebox (R)typebox (E)typebox (A) ────>
                    ├─> storage-area-name ─┤
                    └─> typebox (R)typebox (D)typebox (B)typebox ($)typebox (S)typebox (Y)typebox (S)typebox (T)typebox (E)typebox (M) ────────┘

Additional information available:

RDB$SYSTEM

storage-area-namefile-specstorage-area-options

 The name of the storage area you want to create.

 The storage area file that is associated with the named storage area.
 If you use a simple file name, Rdb/VMS creates the storage area file
 in the current default directory.  Use a name that is unique among
 all storage area files defined for the database.

 The default storage area.  If you directly specify RDB$SYSTEM in the
 DEFINE STORAGE AREA clause, you can override the default
 characteristics for the main storage area.

 Ask for HELP on "DEFINE_DATABASE Format storage-area-options" for
 information on storage area options.

 The name of the storage area that will hold all segmented strings.
 For a single file database or multifile database, if you do not
 explicitly define a storage area for segmented strings, segmented
 strings will be stored in the default storage area, RDB$SYSTEM.  If
 your database is a single-file database and you specify a storage
 area other than RDB$SYSTEM, you receive an error message because
 RDB$SYSTEM is the only storage area in a single-file database.

 The page format for the segmented string storage area can be UNIFORM
 or MIXED.  However, Digital Equipment Corporation recommends that if
 you store segmented strings in a MIXED storage area, that area
 contain only segmented strings.

 Example 1

 Use the default DEFINE DATABASE statement.  If you specify the
 DICTIONARY IS NOT USED clause, the data dictionary will not be used
 to store the database definition and definitions of database
 elements.

 RDO> DEFINE DATABASE 'PERSONNEL'
 cont> DICTIONARY IS NOT USED.


 Example 2

 Use DEFINE DATABASE with qualifiers:

 RDO> DEFINE DATABASE 'PERSONNEL'
 cont> NUMBER OF BUFFERS IS 10
 cont> BUFFER SIZE IS 10 BLOCKS
 cont> DICTIONARY IS NOT USED.

 This statement performs the following actions:

  o  Names the database.

  o  Specifies a number of buffers, and the length of each buffer.

  o  Commits the database definition implicitly.

  o  Specifies that the data dictionary will not be used to store the
     database definition and definitions of database elements.

  o  Invokes the database, using the file name as the database handle.

 Example 3

 The scope of each record's database key is set to FINISH during the
 RDO session of the user who entered DEFINE DATABASE:

 RDO>   DEFINE DATABASE DISK2:[USER.DBS]PERS2
 cont>    DBKEY SCOPE IS FINISH.

 Note that this command does NOT set a "default" DBKEY SCOPE
 characteristic for the database.  For each user, the default is
 COMMIT unless that user specifies INVOKE DATABASE...DBKEY SCOPE
 FINISH.

 Example 4

 The upper limit on the number of VAXcluster nodes from which users
 can access the common, cluster-wide database is set to 8:

 RDO> DEFINE DATABASE ACCTING NUMBER VAXCLUSTER NODES IS 8
 cont> DICTIONARY IS NOT USED.

 If you attempt to access the shared database from a VAXcluster node
 and, in doing so, exceed the maximum nodes parameter, an error is
 signaled to your RDO session or program.

 The DICTIONARY IS NOT USED clause specifies that the data dictionary
 will not be used to store the database definition and definitions of
 database elements.

 Example 5

 The following RDO command procedure defines a multifile database
 called MULTI_PERS.  The example:

  o  Defines database wide characteristics
  o  Defines global storage area defaults
  o  Specifies local attributes for RDB$SYSTEM, the default storage
     area
  o  Defines a storage area for segmented strings
  o  Defines other storage areas


 DEFINE DATABASE 'DB_DISK:MULTI_PERS'
   ! Define database-wide characteristics
      DESCRIPTION IS /* Sample multifile definition */
      NUMBER OF USERS IS 60
      NUMBER OF VAXCLUSTER NODES IS 22
      NUMBER OF RECOVERY BUFFERS IS 200
      DICTIONARY IS NOT USED
   ! Define global storage area characteristics
      ALLOCATION IS 500 PAGES
      PAGE FORMAT IS MIXED
   ! Specify local attributes for the default storage area
   ! Override the global default of MIXED page format
      DEFINE STORAGE AREA RDB$SYSTEM
        FILENAME 'DISK1:PERS_DEFAULT'
        PAGE FORMAT IS UNIFORM
        ALLOCATION IS 300 PAGES
        SNAPSHOT_FILENAME IS 'DISK2:PERS_DEFAULT'
      END RDB$SYSTEM STORAGE AREA
   ! Define storage area for segmented strings
      DEFINE STORAGE AREA PERS_SEGSTR
        FILENAME 'DISK1:PERS_SEGSTR'
        PAGE FORMAT IS UNIFORM
      END PERS_SEGSTR STORAGE AREA
      SEGMENTED STRING STORAGE AREA IS PERS_SEGSTR
   ! Definition of some sample storage areas
      DEFINE STORAGE AREA CANDIDATES
        FILENAME 'DISK3:CANDIDATES'
        PAGE FORMAT IS UNIFORM
        SNAPSHOT_FILENAME IS 'DISK4:CANDIDATES'
      END CANDIDATES STORAGE AREA
      DEFINE STORAGE AREA EMPIDS_LOW
        FILENAME 'DISK5:EMPIDS_LOW'
        SNAPSHOT_FILENAME IS 'DISK6:EMPIDS_LOW'
      END EMPIDS_LOW STORAGE AREA
      DEFINE STORAGE AREA EMPIDS_MID
        FILENAME 'DISK7:EMPIDS_MID'
        SNAPSHOT_FILENAME IS 'DISK8:EMPIDS_MID'
      END EMPIDS_MID STORAGE AREA.