// Copyright 2017 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 distsql import ( "github.com/hanchuanchuan/goInception/kv" "github.com/hanchuanchuan/goInception/sessionctx" "github.com/hanchuanchuan/goInception/statistics" "github.com/hanchuanchuan/goInception/types" "github.com/pingcap/errors" "golang.org/x/net/context" ) // XAPI error codes. const ( codeInvalidResp = 1 ) // Select sends a DAG request, returns SelectResult. // In kvReq, KeyRanges is required, Concurrency/KeepOrder/Desc/IsolationLevel/Priority are optional. func Select(ctx context.Context, sctx sessionctx.Context, kvReq *kv.Request, fieldTypes []*types.FieldType, fb *statistics.QueryFeedback) (SelectResult, error) { // For testing purpose. if hook := ctx.Value("CheckSelectRequestHook"); hook != nil { hook.(func(*kv.Request))(kvReq) } if !sctx.GetSessionVars().EnableStreaming { kvReq.Streaming = false } resp := sctx.GetClient().Send(ctx, kvReq, sctx.GetSessionVars().KVVars) if resp == nil { err := errors.New("client returns nil response") return nil, errors.Trace(err) } if kvReq.Streaming { return &streamResult{ resp: resp, rowLen: len(fieldTypes), fieldTypes: fieldTypes, ctx: sctx, feedback: fb, }, nil } return &selectResult{ label: "dag", resp: resp, results: make(chan resultWithErr, kvReq.Concurrency), closed: make(chan struct{}), rowLen: len(fieldTypes), fieldTypes: fieldTypes, ctx: sctx, feedback: fb, sqlType: "internal", }, nil } // Analyze do a analyze request. func Analyze(ctx context.Context, client kv.Client, kvReq *kv.Request, vars *kv.Variables, isRestrict bool) (SelectResult, error) { resp := client.Send(ctx, kvReq, vars) if resp == nil { return nil, errors.New("client returns nil response") } result := &selectResult{ label: "analyze", resp: resp, results: make(chan resultWithErr, kvReq.Concurrency), closed: make(chan struct{}), feedback: statistics.NewQueryFeedback(0, nil, 0, false), sqlType: "internal", } return result, nil } // Checksum sends a checksum request. func Checksum(ctx context.Context, client kv.Client, kvReq *kv.Request, vars *kv.Variables) (SelectResult, error) { resp := client.Send(ctx, kvReq, vars) if resp == nil { return nil, errors.New("client returns nil response") } result := &selectResult{ label: "checksum", resp: resp, results: make(chan resultWithErr, kvReq.Concurrency), closed: make(chan struct{}), feedback: statistics.NewQueryFeedback(0, nil, 0, false), sqlType: "general", } return result, nil }