Files
tidb/planner/core/encode.go

69 lines
1.8 KiB
Go

// Copyright 2019 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.
package core
import (
"bytes"
"sync"
"github.com/pingcap/tidb/util/plancodec"
)
var encoderPool = sync.Pool{
New: func() interface{} {
return &planEncoder{}
},
}
type planEncoder struct {
buf bytes.Buffer
encodedPlans map[int]bool
}
// EncodePlan is used to encodePlan the plan to the plan tree with compressing.
func EncodePlan(p PhysicalPlan) string {
pn := encoderPool.Get().(*planEncoder)
defer encoderPool.Put(pn)
return pn.encodePlanTree(p)
}
func (pn *planEncoder) encodePlanTree(p PhysicalPlan) string {
pn.encodedPlans = make(map[int]bool)
pn.buf.Reset()
pn.encodePlan(p, true, 0)
return plancodec.Compress(pn.buf.Bytes())
}
func (pn *planEncoder) encodePlan(p PhysicalPlan, isRoot bool, depth int) {
plancodec.EncodePlanNode(depth, p.ID(), p.TP(), isRoot, p.statsInfo().RowCount, p.ExplainInfo(), &pn.buf)
pn.encodedPlans[p.ID()] = true
depth++
for _, child := range p.Children() {
if pn.encodedPlans[child.ID()] {
continue
}
pn.encodePlan(child.(PhysicalPlan), isRoot, depth)
}
switch copPlan := p.(type) {
case *PhysicalTableReader:
pn.encodePlan(copPlan.tablePlan, false, depth)
case *PhysicalIndexReader:
pn.encodePlan(copPlan.indexPlan, false, depth)
case *PhysicalIndexLookUpReader:
pn.encodePlan(copPlan.indexPlan, false, depth)
pn.encodePlan(copPlan.tablePlan, false, depth)
}
}