t8y2/dbx · error

HiveServer2 metadata failed (%v); DESCRIBE fallback failed:

Error message

HiveServer2 metadata failed (%v); DESCRIBE fallback failed: %w

What it means

getColumns first uses HiveServer2 JDBC metadata (GetHiveColumns); if that fails it falls back to running 'DESCRIBE <schema.table>'. This error is raised when the metadata API fails AND the DESCRIBE fallback also fails, embedding the metadata error and wrapping the DESCRIBE error.

Source

Thrown at agents/drivers/hive-go/metadata.go:640

			dataType := metadataString(rows.value(row, "TYPE_NAME"))
			columnSize := metadataIntPointer(rows.value(row, "COLUMN_SIZE"))
			values = append(values, columnInfo{
				Name:                   name,
				DataType:               dataType,
				IsNullable:             metadataNullable(rows.value(row, "NULLABLE", "IS_NULLABLE")),
				ColumnDefault:          optionalString(metadataString(rows.value(row, "COLUMN_DEF"))),
				Comment:                optionalString(metadataString(rows.value(row, "REMARKS", "COMMENT"))),
				NumericPrecision:       columnSize,
				NumericScale:           metadataIntPointer(rows.value(row, "DECIMAL_DIGITS")),
				CharacterMaximumLength: characterLengthForType(dataType, columnSize),
			})
		}
		return values, nil
	}
	qualified := qualifiedHiveName(schema, table)
	result, err := server.executeQuery(queryOptions{SQL: "DESCRIBE " + qualified, MaxRows: metadataQueryLimit})
	if err != nil {
		return nil, fmt.Errorf("HiveServer2 metadata failed (%v); DESCRIBE fallback failed: %w", metadataErr, err)
	}
	values := make([]columnInfo, 0, len(result.Rows))
	for _, row := range result.Rows {
		name := rowString(row, 0)
		if name == "" || strings.HasPrefix(name, "#") {
			continue
		}
		dataType := rowString(row, 1)
		comment := optionalString(rowString(row, 2))
		values = append(values, columnInfo{
			Name:       name,
			DataType:   dataType,
			IsNullable: true,
			Comment:    comment,
		})
	}
	return values, nil
}

View on GitHub (pinned to c0390bff16)

Solutions

1. Verify the table exists and the schema/name casing is correct (run DESCRIBE manually in beeline)
2. Grant the connecting user DESCRIBE/SELECT metadata privileges on the table
3. Check the first (metadata) error for connectivity — a dead connection fails both paths
4. Retry after reconnecting if both errors are transport-related

Example fix

// before: table name with wrong case / missing schema
columns, err := server.getColumns("", "MyTable")
// after: explicit schema and Hive-lowercase name
columns, err := server.getColumns("default", "mytable")

const exists = (await rpc('list_tables', {schema})).tables.some(t => t.name.toLowerCase() === table.toLowerCase())
if (!exists) throw new Error(`table ${schema}.${table} not found`)

cols, err := server.getColumns(schema, table)
if err != nil && strings.Contains(err.Error(), "DESCRIBE fallback failed") {
    log.Printf("cannot read columns for %s.%s: %v", schema, table, err)
}

When it happens

Trigger: Calling get_columns for a table when both the GetHiveColumns metadata call and the DESCRIBE statement fail — e.g. table does not exist, permission denied on the table, or the connection is broken so both calls fail with transport errors.

Common situations: Wrong schema/table name (DESCRIBE on missing table); user without DESCRIBE privileges; connection dropped between the two attempts; case-sensitivity mismatch in the table name.

Related errors

• SHOW DATABASES failed (%v); HiveServer2 metadata fallback fa
• HiveServer2 metadata failed (%v); %s fallback failed: %w
• Hive driver does not expose HiveServer2 metadata RPCs
• table is required
• SQL is required

AI-assisted analysis of t8y2/dbx@c0390bff16 (2026-09-05). Data as JSON: /api/errors/5e94b7993d5e0d22. Report an issue: GitHub.