ATTACH ───┬─> attach-string-literal ────┬─> typebox (;)
           ├─> attach-parameter ─────────┤
           └─> attach-parameter-marker ──┘
 attach-string-literal =

 ──> typebox (') ──> attach-expression ─> typebox (') ───>

Additional information available:

More Informationattach expression

 Specifies the name of a database and the source of the data
 definitions to be accessed by interactive SQL or by a program at run
 time.  Makes the specified database part of the database environment,
 so that you can refer to that database in subsequent CONNECT
 statements.  The database environment is the set of all databases
 with unique aliases in an application.

 The ATTACH statement lets you add new databases at run time:  it has
 no affect on the compilation environment.  To specify the SQL
 environment for compilation, use the DECLARE ALIAS statement.

 If you do not declare any database, SQL declares the database
 specified in the logical name SQL$DATABASE as the default database by
 filename.  See the Help topic on default_database for more
 information.

 attach-expression =
 ─────┬────────────────┬──────┐
      └─> 
A
L
I
A
S alias ─┘      │
 ┌────────────────────────────┘
 └─┬─> 
F
I
L
E
N
A
M
E ─> file-spec ─┬───────────┐
   └─> 
P
A
T
H
N
A
M
E ─> path-name ─┘           │
 ┌────────────────────────────────────────┘
 └┬─────────────────────>───────────────┬─┐
  └─> 
D
B
K
E
Y typebox (S)typebox (C)typebox (O)typebox (P)typebox (E) typebox (I)typebox (S) ─┬──> 
A
T
T
A
C
H ─────┬┘ │
                      └─> 
T
R
A
N
S
A
C
T
I
O
N ─┘  │
 ┌────────────────────────────────────────┘
 └─┬─────────────────────┬──┐
   └─> database options ─┘  │
 ┌──────────────────────────┘
 └─┬────────────────────────────┬───>
   └─> 
M
U
L
T
I
S
C
H
E
M
A 
I
S ─┬─> 
O
N ──┤
                       └─> 
O
F
F ─┘

Additional information available:

FILENAMEPATHNAMEDBKEY_SCOPE_ISMULTISCHEMA_IS_ONMULTISCHEMA_IS_OFF

More InformationExamplesaliasDatabase options

 The attach expression is a character string literal that specifies
 the database environment for the connection.

 The following example attaches the database PERSONNEL in the default
 directory to the default connection and declares the alias Q4_PAYROLL
 for that database.

 SQL> ATTACH 'ALIAS Q4_PAYROLL FILENAME PERSONNEL RDBVMS031';
 SQL>

 The following example attaches the database defined by the file
 specification DISK2:[DEPT3]PERSONNEL to the default connection and
 declares the alias PERS_ALIAS for that database.

 SQL> ATTACH 'ALIAS PERS_ALIAS FILENAME DISK2:[DEPT3]PERSONNEL';
 SQL> SHOW DATABASES;
 Alias PERS_ALIAS:
     Rdb/VMS database in file DISK2:[DEPT3]PERSONNEL


 The following example attaches the database PERSONNEL_NH in the
 current default directory to the default connection and gives that
 database the default alias.

 SQL> ATTACH 'FILENAME PERSONNEL_NH';
 SQL> SHOW DATABASES;
 Default alias:
     Rdb/VMS database in file PERSONNEL_NH

 An alias is a name for a particular attachment to a database.
 Explicitly specifying an alias lets your program or interactive SQL
 statements refer to more than one database.  Once specified, you must
 use the alias when referring to the database in subsequent SQL
 statements (unless those statements are within a CREATE DATABASE or
 CREATE SCHEMA statement).  You must use an alias when you declare
 more than one database.

 DIGITAL proprietary database languages (such as RDO in Rdb/VMS) use
 the term database handle instead of alias.

 FILENAME and PATHNAME both identify the database root file associated
 with the database.  If you specify a data dictionary path name, the
 pathname indirectly specifies the root file.

 FILENAME and PATHNAME both identify the database root file associated
 with the database.  If you specify a data dictionary path name, the
 pathname indirectly specifies the root file.
 The following example uses the data dictionary definition with the
 pathname CDD$DEFAULT.DEPT3.PERSONNEL to invoke the PERSONNEL to the
 default connection and declares the alias PERS_ALIAS for that
 database.

 SQL> ATTACH 'ALIAS DICT_PERS PATHNAME CDD$DEFAULT.DEPT3.PERSONNEL';
 SQL> SHOW DATABASES;
 Alias DICT_PERS:
     data dictionary pathname is DISK01:[CDDPLUS]DEPT3.PERSONNEL;1
     Rdb/VMS database in file DISK02:[CORPORATE.DEPT3]PERSONNEL.RDB;
 SQL>

 Controls when the database key of an erased record may be used again
 by SQL.

 The default is DBKEY SCOPE IS TRANSACTION, which means that SQL can
 reuse the database key of a deleted table row as soon you commit the
 transaction that deleted the original row and disconnect the
 connection.

 For more information, type HELP DBKEY.

 The database options specify types of supported databases that your
 application can access.  Specifying database options in the ATTACH
 statement overrides the default established in the precompiler or
 module language command line.

 Enables multischema naming for the duration of the database
 attachment.

 Disables multischema naming for the duration of the database
 attachment.  Multischema naming is disabled by default.