Mapping Ingres Star Objects

Ingres Star recognizes and manages three types of queryable objects: tables, views, and indexes. It also maps procedures, which are not queryable but may be executed.

Registered Names and Related Catalogs

The basic function of a registered name is to allow a local queryable object to be given the status of a queryable object in the distributed database. The register as link statement does this by registering a name in the distributed database to denote a queryable object in a local database. This allows you to use a registered name to denote its underlying object.

To support registered name transparency, it is necessary for Ingres Star to promote the complete information about the local object from the local database catalogs into Ingres Star's equivalent catalogs and classify the information under the registered name and the owner of the registered name.

Tables and Related Catalogs

A table's local catalog information is promoted into the Ingres Star catalogs as follows:

• From the local database's iitables to Ingres Star's iitables
• From the local database's iicolumns to Ingres Star's iicolumns
• From the local database's iiphysical_tables to Ingres Star's iiphysical_tables
• From the local database's iiindex_columns to Ingres Star's iiindex_columns
• From the local database's iialt_columns to Ingres Star's iiialt_columns

Index Mapping

Each index of a local table introduced by a register is promoted as an index and given a registered name composed of the prefix ddx, the base, and the index of the object id, separated by the special character, _, for example, ddx_2002_2003.

Indexes are automatically mapped during the register statement to iiindexes and iiindex_columns. You cannot create secondary indexes with Ingres Star.

Table and Column Mapping

If no column mapping is specified during the register as link statement, data is promoted from the local database's iicolumns to Ingres Star's iicolumns.

• The local information is stored in the Ingres Star-specific catalog iiddb_ldb_columns. The representation in iiddb_ldb_columns is used exclusively by Ingres Star.
• The column information of the registered name is stored in Ingres Star's iicolumns standard catalog.

Ingres Star provides column mapping if either the distributed database or the local database (but not both) support mixed-case delimited identifiers.

Physical Information and Statistics Mapping

If the local object is an index or table (not a view), more relevant information is transferred:

• from the local database's iihistograms to Ingres Star's iihistograms
• from the local database's iistats to Ingres Star's iistats

This is promoted only if the environments are compatible, that is, the hardware and operating system are the same on the local database's node as on the distributed database's node.

Statistics information is not promoted if the local database and distributed database are in heterogeneous environments. To obtain statistics in such an environment, you must run optimizedb.

Local Tables Index Information

If the local table is in an Ingres database, each index is also registered. Note that Enterprise Access indexes might not be promoted to Ingres Star.

Views and Related Catalogs

When a view is created, its information is stored in several Ingres Star catalogs that include the following standard catalogs:

• iicolumns
• iitables
• iiviews
• iiphysical_tables

Registered Procedures and Related Catalogs

When Ingres Star registers procedures, it maps a local procedure and local owner name to a distributed procedure and distributed owner name. It does not map procedure parameters; it merely passes those through to the local DBMS when the procedure is executed.

Registered procedures are stored in the following standard catalogs:

• iiregistrations
• iiprocedures

Note: Registered procedures are not stored in the iitables standard catalog.