Hive Schema refresh failed, No tables are visible

I am connected to Hive data source and I am also able to query any tables available in Hive database, But Redash does not show the all available tables on left panel. It complains “Schema refresh failed.”

I tried to run the specific queries related to schema information like “Show schemas” or “Show tables in [Schemas]”. Even I am able to run these queries in beeline using hive user.

I am using 8.x version in docker.


I got the same problem.
That’s because it takes too long to get the schema information.
The source code is as follows:

    def _get_tables(self, schema):
        schemas_query = "show schemas"

        tables_query = "show tables in %s"

        columns_query = "show columns in %s.%s"

        for schema_name in filter(lambda a: len(a) > 0, map(lambda a: str(a['database_name']), self._run_query_internal(schemas_query))):
            for table_name in filter(lambda a: len(a) > 0, map(lambda a: str(a['tab_name']), self._run_query_internal(tables_query % schema_name))):
                columns = filter(lambda a: len(a) > 0, map(lambda a: str(a['field']), self._run_query_internal(columns_query % (schema_name, table_name))))

                if schema_name != 'default':
                    table_name = '{}.{}'.format(schema_name, table_name)

                schema[table_name] = {'name': table_name, 'columns': columns}
        return schema.values()

I had soved this kind problem.

I created a new data table to store the schema information. I get the schema information from hive at regular times every day and stored them into the table. Then I modified the source code of Redash so that Redash could get the schema information from the table(mysql or pg), and the problem was solved

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