schema

The PegaRULES database as initially installed includes about 70 tables in a single database instance. Each table stores the persistent objects from one or more concrete classes. The schema (structure and layout) for the database is documented as HTML topics available in the /schema directory of the installation media.

Columns for the table correspond to Single Value properties in the object. Some aggregate property values are stored in a single special column named pzPVStream, known as the Storage Stream. Binary values (such as a floating point value, JPG image or DLL file) are converted to text using Base64 encoding and stored in a binary large object column (BLOB), known as the Storage Stream.

A database administrator can view, extend update, and manage the database schema. Certain changes to the database schema must be carefully coordinated with changes to Database and Database Table data instances.

Multiple schemas

One database instance can support multiple separate PRPC systems, using distinct schemas. However, the prconfig.xml file of each system must correctly identify the schema to use.

To identify a schema within a database instance, add the following line to the prconfig.xml file after installation:

<env name="database/baseTable/schema" value="zzzzz" />

where zzzzz is the schema name. See PDN article Troubleshooting: "Obj-Save is trying to write to a non-existent column".

As an alternative to the prconfig.xml file, you can use Dynamic System Settings to configure your application.

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