KeyError 'table.head' when running validator.head() using IBM DB2 datasource

[Adenmin]

Hello there again!

I continue working on integration GE and IBM Db2
and I already fixed issue #5579 by upgrading GE to 0.15.15
but I faced new issue...

Environment:
Operating System: Linux Ubuntu 22.04
Great Expectations Version: 0.15.15
ibm-db Version: 3.1.2
ibm-db-sa Version: 0.3.8
SQLAlchemy Version: 1.4.39

Config

datasources:
  db2_test_datasource:
    class_name: Datasource
    data_connectors:
      default_runtime_data_connector_name:
        class_name: RuntimeDataConnector
        module_name: great_expectations.datasource.data_connector
        batch_identifiers:
          - default_identifier_name
      default_inferred_data_connector_name:
        class_name: InferredAssetSqlDataConnector
        include_schema_name: true
        module_name: great_expectations.datasource.data_connector
    module_name: great_expectations.datasource
    execution_engine:
      module_name: great_expectations.execution_engine
      class_name: SqlAlchemyExecutionEngine
      connection_string: ibm_db_sa://admin:admin@127.0.0.1:50000/TEST

run it

context = ge.data_context.DataContext()

batch_request = RuntimeBatchRequest(
    datasource_name="db2_test_datasource",
    data_connector_name="default_runtime_data_connector_name",
    data_asset_name="default_name",  # this can be anything that identifies this data
    runtime_parameters={"query": "SELECT * FROM TEST_TABLE LIMIT 10"},
    batch_identifiers={"default_identifier_name": "default_identifier"},
)
context.create_expectation_suite(
    expectation_suite_name="test_suite", overwrite_existing=True
)
validator = context.get_validator(
    batch_request=batch_request, expectation_suite_name="test_suite"
)
print(validator.head())

and I got

KeyError: ('table.head', 'batch_id=
... 
raise ge_exceptions.MetricResolutionError(\ngreat_expectations.exceptions.exceptions.MetricResolutionError: (ibm_db_dbi.ProgrammingError) ibm_db_dbi::ProgrammingError: SQLNumResultCols failed: [IBM][CLI Driver][DB2/LINUXX8664] SQL0204N  "ADMIN.GE_TEMP_C844EBCD" is an undefined name.  SQLSTATE=42704 SQLCODE=-204\n[SQL: SELECT * \nFROM ge_temp_c844ebcd FETCH FIRST 5 ROWS ONLY]\n(Background on this error at: https://sqlalche.me/e/14/f405)\n', 'exception_message': '(ibm_db_dbi.ProgrammingError) ibm_db_dbi::ProgrammingError: SQLNumResultCols failed: [IBM][CLI Driver][DB2/LINUXX8664] SQL0204N  "ADMIN.GE_TEMP_C844EBCD" is an undefined name.  SQLSTATE=42704 SQLCODE=-204\n[SQL: SELECT * \nFROM ge_temp_c844ebcd FETCH FIRST 5 ROWS ONLY]\n(Background on this error at: https://sqlalche.me/e/14/f405)', 'raised_exception': True}}}}

Looks like something wrong with temp tables.
I saw some similar issues about validator.head()
#5424
#5478
but I'm not sure that they have common root cause.

[rdodev]

Hey @Adenmin 👋

Unfortunately GX doesn't support DB2 dialect and we have no immediate plans to implement it. However, if you're inclined, we'll happily accept a contribution (and guide you through the process).

[rdodev]

For now, I'm converting this issue into a Github Discussion for further discussion.