vitess.io/vitess@v0.16.2/go/vt/vtgate/planbuilder/operators/horizon.go (about) 1 /* 2 Copyright 2022 The Vitess Authors. 3 4 Licensed under the Apache License, Version 2.0 (the "License"); 5 you may not use this file except in compliance with the License. 6 You may obtain a copy of the License at 7 8 http://www.apache.org/licenses/LICENSE-2.0 9 10 Unless required by applicable law or agreed to in writing, software 11 distributed under the License is distributed on an "AS IS" BASIS, 12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 See the License for the specific language governing permissions and 14 limitations under the License. 15 */ 16 17 package operators 18 19 import ( 20 "vitess.io/vitess/go/vt/sqlparser" 21 "vitess.io/vitess/go/vt/vtgate/planbuilder/operators/ops" 22 "vitess.io/vitess/go/vt/vtgate/planbuilder/plancontext" 23 ) 24 25 // Horizon is an operator we use until we decide how to handle the source to the horizon. 26 // It contains information about the planning we have to do after deciding how we will send the query to the tablets. 27 type Horizon struct { 28 Source ops.Operator 29 Select sqlparser.SelectStatement 30 31 noColumns 32 } 33 34 var _ ops.Operator = (*Horizon)(nil) 35 var _ ops.PhysicalOperator = (*Horizon)(nil) 36 37 func (h *Horizon) IPhysical() {} 38 39 func (h *Horizon) AddPredicate(ctx *plancontext.PlanningContext, expr sqlparser.Expr) (ops.Operator, error) { 40 newSrc, err := h.Source.AddPredicate(ctx, expr) 41 if err != nil { 42 return nil, err 43 } 44 h.Source = newSrc 45 return h, nil 46 } 47 48 func (h *Horizon) Clone(inputs []ops.Operator) ops.Operator { 49 return &Horizon{ 50 Source: inputs[0], 51 Select: h.Select, 52 } 53 } 54 55 func (h *Horizon) Inputs() []ops.Operator { 56 return []ops.Operator{h.Source} 57 }