SQL/MX Comparison Guide for SQL/MP Users

HP NonStop SQL/MX Comparison Guide for SQL/MP Users—523735-003
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Data Definition Language (DDL)
Differences
With NonStop SQL/MX Release 2, NonStop SQL/MX can now create objects. Prior to
Release 2, NonStop SQL/MX did not allow creation of objects. NonStop SQL/MX can
access NonStop SQL/MX as well as SQL/MP files. New Data Definition Language
(DDL) statements allow you to create and modify application files. For details on these
statements, see “SQL/MX Statements” in the SQL/MX Reference Manual.
SQL Statements
You can now create, alter, and drop SQL/MX database objects similarly to how you
manipulate these objects in NonStop SQL/MP, with these exceptions:
•
You cannot create collations for SQL/MX tables, so there is no CREATE
COLLATION statement. You create constraints at CREATE TABLE time or later
with a ALTER TABLE ADD CONSTRAINT statement, so there is no separate
CREATE CONSTRAINT statement. You drop constraints with the ALTER TABLE
DROP CONSTRAINT statement.
•
You cannot alter catalogs, collations, programs or views.
•
The generic DROP command has been replaced by specific DROP CATALOG,
DROP INDEX, DROP PROCEDURE, DROP SCHEMA, DROP SQL, DROP
SQLMP ALIAS, DROP TABLE, DROP TRIGGER, and DROP VIEW statements.
See the SQL/MX Reference Manual for information about statements and database
objects.
Database Object Names
You must use ANSI logical names (a three-part logical name: catalog-name. schema-
name.object-name) to describe SQL/MX objects, using the LOCATION clause to
specify their physical location.
You can use physical names, ANSI logical names, SQL/MP alias names, or DEFINE
names to refer to SQL/MP objects.
See “SQL/MX Language Elements” in the SQL/MX Reference Manual for details about
database object names.
ANSI Names
Namespace for SQL/MX objects is organized in a hierarchical manner. Database
objects exist in schemas, which are themselves contained in catalogs. Catalogs are