Method queryStatement

backend/plugin/db/spanner/spanner.go:392–442

(ctx context.Context, statement string, queryContext db.QueryContext)

}

func (d *Driver) queryStatement(ctx context.Context, statement string, queryContext db.QueryContext) (*v1pb.QueryResult, error) {
	iter := d.client.Single().Query(ctx, spanner.NewStatement(statement))
	defer iter.Stop()

	row, err := iter.Next()
	if err == iterator.Done {
		// Empty result set - return empty QueryResult with column info
		columnTypeNames, typeErr := getColumnTypeNames(iter)
		if typeErr != nil {
			return nil, typeErr
		}
		return &v1pb.QueryResult{
			ColumnNames:     getColumnNames(iter),
			ColumnTypeNames: columnTypeNames,
		}, nil
	}
	if err != nil {
		return nil, err
	}

	columnTypeNames, err := getColumnTypeNames(iter)
	if err != nil {
		return nil, err
	}
	result := &v1pb.QueryResult{
		ColumnNames:     getColumnNames(iter),
		ColumnTypeNames: columnTypeNames,
	}

	for {
		rowData, err := readRow(row)
		if err != nil {
			return nil, err
		}
		result.Rows = append(result.Rows, rowData)
		n := len(result.Rows)
		if (n&(n-1) == 0) && int64(proto.Size(result)) > queryContext.MaximumSQLResultSize {
			result.Error = common.FormatMaximumSQLResultSizeMessage(queryContext.MaximumSQLResultSize)
			break
		}

		row, err = iter.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			return nil, err
		}
	}
	return result, nil
}

// convertSpannerValue converts google.protobuf.Value to RowValue.
// Uses type metadata to preserve INT64 precision and properly handle all Spanner types.