func (ta *Table) fetchIndexes(conn mysql.Executer) error {
	r, err := conn.Execute(fmt.Sprintf("show index from %s.%s", ta.Schema, ta.Name))
	if err != nil {
		return err
	}
	var currentIndex *Index
	currentName := ""

	for i := 0; i < r.RowNumber(); i++ {
		indexName, _ := r.GetString(i, 2)
		if currentName != indexName {
			currentIndex = ta.AddIndex(indexName)
			currentName = indexName
		}
		cardinality, _ := r.GetUint(i, 6)
		colName, _ := r.GetString(i, 4)
		currentIndex.AddColumn(colName, cardinality)
	}

	if len(ta.Indexes) == 0 {
		return nil
	}

	pkIndex := ta.Indexes[0]
	if pkIndex.Name != "PRIMARY" {
		return nil
	}

	ta.PKColumns = make([]int, len(pkIndex.Columns))
	for i, pkCol := range pkIndex.Columns {
		ta.PKColumns[i] = ta.FindColumn(pkCol)
	}

	return nil
}
func (ta *Table) fetchColumns(conn mysql.Executer) error {
	r, err := conn.Execute(fmt.Sprintf("describe %s.%s", ta.Schema, ta.Name))
	if err != nil {
		return err
	}

	for i := 0; i < r.RowNumber(); i++ {
		name, _ := r.GetString(i, 0)
		colType, _ := r.GetString(i, 1)
		extra, _ := r.GetString(i, 5)

		ta.AddColumn(name, colType, extra)
	}

	return nil
}