How to create an IDMS SQL schema for multiple non-sql databases without the DBNAME in the definition?

Products

• IDMS

Issue/Introduction

There are many physical database segments that are currently accessed via different DBNAMEs but use only the one non-SQL schema, and we want to replicate that with the one SQL schema.

Resolution

Defining an SQL schema, against a network schema, without a DBNAME can work, but you need to be aware of a couple of things. 
The DBNAME you connect to (at runtime when you issue your SELECT or other SQL commands)  needs to contain the following:
1. SQL catalog (to retrieve the SQL schema that was created)
2. the network dictionary where the network schema resides (this is because IDMS will access that dictionary at run time to retrieve the schema definition)
3. the segments that contain the network data that you are trying to access.  

In the network world, we can separate the DICTNAME (where the subschema load module resides, ie the database definition) and the DBNAME (where the data resides).
With SQL the DBNAME is used for both, so it must contain all the above info.