[parser] parser: support index advisor (#667)

parser/ast/advisor.go

@@ -0,0 +1,80 @@
+// 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 ast
+
+import (
+ . "github.com/pingcap/parser/format"
+)
+
+var _ StmtNode = &IndexAdviseStmt{}
+
+// IndexAdviseStmt is used to advise indexes
+type IndexAdviseStmt struct {
+ stmtNode
+
+ IsLocal bool
+ Path string
+ MaxMinutes uint64
+ MaxIndexNum *MaxIndexNumClause
+ LinesInfo *LinesClause
+}
+
+// Restore implements Node Accept interface.
+func (n *IndexAdviseStmt) Restore(ctx *RestoreCtx) error {
+ ctx.WriteKeyWord("INDEX ADVISE ")
+ if n.IsLocal {
+ ctx.WriteKeyWord("LOCAL ")
+ }
+ ctx.WriteKeyWord("INFILE ")
+ ctx.WriteString(n.Path)
+ if n.MaxMinutes != UnspecifiedSize {
+ ctx.WriteKeyWord(" MAX_MINUTES ")
+ ctx.WritePlainf("%d", n.MaxMinutes)
+ }
+ if n.MaxIndexNum != nil {
+ n.MaxIndexNum.Restore(ctx)
+ }
+ n.LinesInfo.Restore(ctx)
+ return nil
+}
+
+// Accept implements Node Accept interface.
+func (n *IndexAdviseStmt) Accept(v Visitor) (Node, bool) {
+ newNode, skipChildren := v.Enter(n)
+ if skipChildren {
+ return v.Leave(newNode)
+ }
+ n = newNode.(*IndexAdviseStmt)
+ return v.Leave(n)
+}
+
+// MaxIndexNumClause represents 'maximum number of indexes' clause in index advise statement.
+type MaxIndexNumClause struct {
+ PerTable uint64
+ PerDB uint64
+}
+
+// Restore for max index num clause
+func (n *MaxIndexNumClause) Restore(ctx *RestoreCtx) error {
+ ctx.WriteKeyWord(" MAX_IDXNUM")
+ if n.PerTable != UnspecifiedSize {
+ ctx.WriteKeyWord(" PER_TABLE ")
+ ctx.WritePlainf("%d", n.PerTable)
+ }
+ if n.PerDB != UnspecifiedSize {
+ ctx.WriteKeyWord(" PER_DB ")
+ ctx.WritePlainf("%d", n.PerDB)
+ }
+ return nil
+}

parser/ast/util.go

@@ -13,6 +13,13 @@
 
 package ast
 
+import "math"
+
+// UnspecifiedSize is unspecified size.
+const (
+ UnspecifiedSize = math.MaxUint64
+)
+
 // IsReadOnly checks whether the input ast is readOnly.
 func IsReadOnly(node Node) bool {
  switch st := node.(type) {

parser/misc.go

@@ -138,6 +138,7 @@ var tokenMap = map[string]int{
  "ACTION": action,
  "ADD": add,
  "ADDDATE": addDate,
+ "ADVISE": advise,
  "ADMIN": admin,
  "AFTER": after,
  "AGAINST": against,
@@ -393,6 +394,8 @@ var tokenMap = map[string]int{
  "MAX": max,
  "MAX_CONNECTIONS_PER_HOUR": maxConnectionsPerHour,
  "MAX_EXECUTION_TIME": maxExecutionTime,
+ "MAX_IDXNUM": max_idxnum,
+ "MAX_MINUTES": max_minutes,
  "MAX_QUERIES_PER_HOUR": maxQueriesPerHour,
  "MAX_ROWS": maxRows,
  "MAX_UPDATES_PER_HOUR": maxUpdatesPerHour,
@@ -461,6 +464,8 @@ var tokenMap = map[string]int{
  "PARTITIONS": partitions,
  "PASSWORD": password,
  "PESSIMISTIC": pessimistic,
+ "PER_TABLE": per_table,
+ "PER_DB": per_db,
  "PLUGINS": plugins,
  "POSITION": position,
  "PRECEDING": preceding,