SQL/MX 3.2.1 Management Manual (H06.26+, J06.15+)

Guardian Physical Names
The underlying Guardian physical names of SQL/MX objects and SQL/MP objects are qualified
with the system node, volume, and subvolume names. For example, SQL/MP tables and views are
created with Guardian physical names of the form:
[\node.] [[$volume.]subvol.]filename
In this four-part name, \node is the name of a node on an HP NonStop system, $volume is the
name of a disk volume, subvol is the name of a subvolume, and filename is the name of a
Guardian disk file or the name of an SQL/MP table or view.
SQL/MX data is stored in files with Guardian physical names. In turn, these files are associated
with ANSI names.
For more information about using Guardian physical names for SQL/MP objects, see the SQL/MP
Reference Manual and the SQL/MP Installation and Management Guide.
DEFINE Names
Use class MAP DEFINE names as logical names for SQL/MP tables or views in DML statements.
When NonStop SQL/MX compiles such statements, it replaces the DEFINE name in the statement
with the associated Guardian physical name. You can create DEFINE names within MXCI or names
can be inherited from the TACL process or the OSS shell.
You cannot assign DEFINE names to SQL/MX tables or views. However, you can use prototyped
host variables to name SQL/MX tables or views in C and COBOL programs. For more information,
see the SQL/MX Programming Manual for C and COBOL.
For more information, see the SQL/MX Programming Manual for C and COBOL.
PROTOTYPE
You can dynamically change the name of a table or a view in an embedded SQL statement using
a host variable to provide the table name during execution. After you declare a host variable for
the table name, you can use the PROTOTYPE to specify the host variable within an embedded SQL
statement. You must initialize the value of the PROTOTYPE host variable before executing the
embedded SQL statement. For more information on the PROTOTYPE host variables for SQL/MP
and SQL/MX objects, see the SQL/MX Programming Manual for C and COBOL.
Object Namespaces
Multiple objects with the same logical name can exist in the same schema, provided each belongs
to a different namespace. For more information, see the SQL/MX Reference Manual.
Using ANSI Names for SQL/MP Objects
NonStop SQL/MX supports the use of ANSI names (SQL/MP aliases) to query SQL/MP database
objects. The mapping from ANSI logical name to physical SQL/MP partition is stored in the
MP_PARTITIONS table in the definition schema.
For more information about logical-to-physical name mapping using SQL/MP aliases, see the
SQL/MX Reference Manual.
SQL/MX Metadata
NonStop SQL/MX stores system metadata for all SQL/MX format objects in SQL/MX tables,
automatically creating and maintaining metadata as users create, alter, drop, or update SQL/MX
objects. The metadata maintains an accurate record of the information that constitutes the definition
of SQL/MX objects and how the objects are used by other SQL/MX objects.
System metadata about objects is stored in numerous tables in system schemas and definition
schemas. You cannot modify data in these system metadata tables directly. However, they are
SQL/MX Metadata 23