github.com/whtcorpsinc/milevadb-prod@v0.0.0-20211104133533-f57f4be3b597/causetstore/petri/acyclic/causet/memo/implementation.go (about)

     1  // Copyright 2020 WHTCORPS INC, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package memo
    15  
    16  import (
    17  	causetembedded "github.com/whtcorpsinc/milevadb/causet/embedded"
    18  )
    19  
    20  // Implementation defines the interface for cost of physical plan.
    21  type Implementation interface {
    22  	CalcCost(outCount float64, children ...Implementation) float64
    23  	SetCost(cost float64)
    24  	GetCost() float64
    25  	GetCauset() causetembedded.PhysicalCauset
    26  
    27  	// AttachChildren is used to attach children implementations and returns it self.
    28  	AttachChildren(children ...Implementation) Implementation
    29  
    30  	// GetCostLimit gets the costLimit for implementing the next childGroup.
    31  	GetCostLimit(costLimit float64, children ...Implementation) float64
    32  }