An ODBC request fails with error SQLDA TRUNCATED - NEEDED 313 ENTRIES (State:S1C00, Native Code:FFFFFF78) which corresponds to an SQL code -136
The CA Datacom Server code is architected and structured such that it can handle only 300 columns in a request or in a table/view definition.
You can create an SQL VIEW on that table that uses lesser columns than 300 and use this view in your SQL request.
This limitation is documented in the CA Datacom Server User Guide as follows:
"You can specify masking to limit the lists of tables and views presented for user selection. CA Datacom Server lets you limit the tables and views the server returns in response to the SQLTables function because when accessing mainframe CA Datacom/DB, these lists can be long. CA Datacom Server has a 300-column limit in a table that it can handle in a single result set, UPDATE, or SELECT request."