t8y2/dbx · error

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

Error message

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

What it means

Column listing (getColumns/describe) tries HiveServer2 metadata (GetHiveColumns) first; on failure it runs 'DESCRIBE <schema>.<table>' as a fallback. This error is returned only when the metadata call AND the DESCRIBE fallback both fail, wrapping the metadata error (%v) and the DESCRIBE error (%w).

Source

Thrown at agents/drivers/argo-go/metadata.go:629

			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: run SHOW TABLES IN <schema> and confirm the exact name/case.
  2. Run 'DESCRIBE <schema>.<table>' manually as the same user to see the underlying failure.
  3. Check the user has SELECT/DESCRIBE privileges on the table.
  4. Reconnect if the session was dropped (both attempts failing together often indicates a dead session).

Example fix

// before
getColumns(schema: "sales", table: "orderss")
// after
getColumns(schema: "sales", table: "orders")
Defensive patterns

Strategy: validation

Validate before calling

// Verify the table exists before asking for its columns.
func tableExists(server *server, schema, table string) bool {
    tables, err := server.listTables(schema, metadataListConstraints{Filter: table})
    if err != nil {
        return false
    }
    for _, t := range tables {
        if strings.EqualFold(t.Name, table) {
            return true
        }
    }
    return false
}
if !tableExists(server, "sales", "orders") {
    return nil, fmt.Errorf("table %s.%s does not exist or is not accessible", "sales", "orders")
}

Try / catch

cols, err := server.getColumns(schema, table)
if err != nil {
    var inner error
    if errors.As(err, &inner) {
        log.Printf("describe failed for %s.%s: %v", schema, table, inner)
    }
    if !tableExists(server, schema, table) {
        return nil, fmt.Errorf("unknown table %s.%s", schema, table)
    }
    return fmt.Errorf("column metadata unavailable: %w", err)
}

Prevention

When it happens

Trigger: Requesting columns for a table when the JDBC metadata call fails and 'DESCRIBE schema.table' also fails — typically the table does not exist, is misspelled, or the user lacks describe privileges.

Common situations: Wrong schema/table name in the request (typos, wrong case); table dropped or renamed; user without DESC privileges; connection dropped between the two attempts.

Related errors

AI-assisted analysis of t8y2/dbx@c0390bff16 (2026-09-05). Data as JSON: /api/errors/817b69328f88073d. Report an issue: GitHub.