Persist and expose Virtual Schema column nullability metadata in system views.
Details
| Detail name | Value |
|---|---|
| Changelog Number | 21012 |
| Type | Improvement |
| Status | Resolved |
| Fix Versions | Exasol 2026.1.1, Exasol 2025.1.12 |
| Resolution Date | 2026-07-02 |
Background
It was possible for virtual schema columns to have incorrect nullability information in Exasol metadata views when the virtual schema adapter defined the column nullability. This issue occurred when the adapter provided nullability information for a column. In this situation, the nullability information was not exposed through EXA_DBA_COLUMNS.
As a result, queries against Exasol metadata views could return incorrect nullability information for virtual schema columns.
Improvement
The nullability information provided by virtual schema adapters is now correctly exposed through EXA_DBA_COLUMNS. Queries against Exasol metadata views now return the nullability defined by the virtual schema adapter.
Changed behavior
Fix introduces a minor change to JSON messages send from DB to VS adapter.
SELECTs to Virtual Schemas created prior to Fix Versions could fail with error mentioning "org.glassfish.json.JsonObjectBuilderImpl$JsonObjectImpl.getBoolean".
To avoid these errors, either run ALTER SCHEMA REFRESH after DB update or prior to update install a Virtual Schema JAR based on "virtual-schema-common-java" 14.0.5 or newer. E.g., for PostgreSQL Virtual Schema it's release 4.0.2 and respectively file "virtual-schema-dist-14.0.5-postgresql-4.0.2.jar".
