Files
tidb/executor/compiler.go
David Chen f1e89cde19 *: use lower-case of github.com/sirupsen/logrus (#5400)
*: rename github.com/Sirupsen/logrus to github.com/sirupsen/logrus

* vendor: update pd

* vendor: update github.com/pingcap/tipb/go-mysqlx
2017-12-14 16:25:58 +08:00

73 lines
2.2 KiB
Go

// Copyright 2015 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 executor
import (
"github.com/juju/errors"
"github.com/opentracing/opentracing-go"
"github.com/pingcap/tidb/ast"
"github.com/pingcap/tidb/context"
"github.com/pingcap/tidb/infoschema"
"github.com/pingcap/tidb/plan"
log "github.com/sirupsen/logrus"
goctx "golang.org/x/net/context"
)
// Compiler compiles an ast.StmtNode to a physical plan.
type Compiler struct {
Ctx context.Context
}
// Compile compiles an ast.StmtNode to a physical plan.
func (c *Compiler) Compile(goCtx goctx.Context, stmtNode ast.StmtNode) (*ExecStmt, error) {
if span := opentracing.SpanFromContext(goCtx); span != nil {
span1 := opentracing.StartSpan("executor.Compile", opentracing.ChildOf(span.Context()))
defer span1.Finish()
}
infoSchema := GetInfoSchema(c.Ctx)
if err := plan.Preprocess(c.Ctx, stmtNode, infoSchema, false); err != nil {
return nil, errors.Trace(err)
}
finalPlan, err := plan.Optimize(c.Ctx, stmtNode, infoSchema)
if err != nil {
return nil, errors.Trace(err)
}
return &ExecStmt{
InfoSchema: infoSchema,
Plan: finalPlan,
Expensive: stmtCount(stmtNode, finalPlan, c.Ctx.GetSessionVars().InRestrictedSQL),
Cacheable: plan.Cacheable(stmtNode),
Text: stmtNode.Text(),
StmtNode: stmtNode,
Ctx: c.Ctx,
}, nil
}
// GetInfoSchema gets TxnCtx InfoSchema if snapshot schema is not set,
// Otherwise, snapshot schema is returned.
func GetInfoSchema(ctx context.Context) infoschema.InfoSchema {
sessVar := ctx.GetSessionVars()
var is infoschema.InfoSchema
if snap := sessVar.SnapshotInfoschema; snap != nil {
is = snap.(infoschema.InfoSchema)
log.Infof("[%d] use snapshot schema %d", sessVar.ConnectionID, is.SchemaMetaVersion())
} else {
is = sessVar.TxnCtx.InfoSchema.(infoschema.InfoSchema)
}
return is
}