func (v *explainVisitor) explain(p plan.Plan) {
switch x := p.(type) {
case *plan.TableScan:
v.entries = append(v.entries, v.newEntryForTableScan(x))
case *plan.IndexScan:
v.entries = append(v.entries, v.newEntryForIndexScan(x))
case *plan.Sort:
v.sort = true
}
for _, c := range p.GetChildren() {
v.explain(c)
}
}
func (e *ExplainExec) prepareExplainInfo(p plan.Plan, parent plan.Plan) error {
for _, child := range p.GetChildren() {
err := e.prepareExplainInfo(child, p)
if err != nil {
return errors.Trace(err)
}
}
explain, err := json.MarshalIndent(p, "", " ")
if err != nil {
return errors.Trace(err)
}
parentStr := ""
if parent != nil {
parentStr = parent.GetID()
}
row := &Row{
Data: types.MakeDatums(p.GetID(), string(explain), parentStr),
}
e.rows = append(e.rows, row)
return nil
}