b6a95a8cb3
* Dropped unused codekit config * Integrated dynamic and static bindata for public * Ignore public bindata * Add a general generate make task * Integrated flexible public assets into web command * Updated vendoring, added all missiong govendor deps * Made the linter happy with the bindata and dynamic code * Moved public bindata definition to modules directory * Ignoring the new bindata path now * Updated to the new public modules import path * Updated public bindata command and drop the new prefix
925 lines
28 KiB
Go
925 lines
28 KiB
Go
// Copyright 2015 PingCAP, Inc.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package optimizer
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import (
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"fmt"
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"github.com/juju/errors"
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"github.com/pingcap/tidb/ast"
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"github.com/pingcap/tidb/column"
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"github.com/pingcap/tidb/context"
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"github.com/pingcap/tidb/infoschema"
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"github.com/pingcap/tidb/model"
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"github.com/pingcap/tidb/mysql"
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"github.com/pingcap/tidb/sessionctx/db"
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"github.com/pingcap/tidb/util/types"
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)
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// ResolveName resolves table name and column name.
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// It generates ResultFields for ResultSetNode and resolves ColumnNameExpr to a ResultField.
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func ResolveName(node ast.Node, info infoschema.InfoSchema, ctx context.Context) error {
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defaultSchema := db.GetCurrentSchema(ctx)
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resolver := nameResolver{Info: info, Ctx: ctx, DefaultSchema: model.NewCIStr(defaultSchema)}
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node.Accept(&resolver)
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return errors.Trace(resolver.Err)
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}
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// nameResolver is the visitor to resolve table name and column name.
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// In general, a reference can only refer to information that are available for it.
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// So children elements are visited in the order that previous elements make information
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// available for following elements.
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//
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// During visiting, information are collected and stored in resolverContext.
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// When we enter a subquery, a new resolverContext is pushed to the contextStack, so subquery
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// information can overwrite outer query information. When we look up for a column reference,
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// we look up from top to bottom in the contextStack.
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type nameResolver struct {
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Info infoschema.InfoSchema
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Ctx context.Context
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DefaultSchema model.CIStr
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Err error
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useOuterContext bool
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contextStack []*resolverContext
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}
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// resolverContext stores information in a single level of select statement
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// that table name and column name can be resolved.
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type resolverContext struct {
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/* For Select Statement. */
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// table map to lookup and check table name conflict.
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tableMap map[string]int
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// table map to lookup and check derived-table(subselect) name conflict.
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derivedTableMap map[string]int
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// tableSources collected in from clause.
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tables []*ast.TableSource
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// result fields collected in select field list.
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fieldList []*ast.ResultField
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// result fields collected in group by clause.
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groupBy []*ast.ResultField
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// The join node stack is used by on condition to find out
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// available tables to reference. On condition can only
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// refer to tables involved in current join.
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joinNodeStack []*ast.Join
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// When visiting TableRefs, tables in this context are not available
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// because it is being collected.
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inTableRefs bool
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// When visiting on conditon only tables in current join node are available.
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inOnCondition bool
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// When visiting field list, fieldList in this context are not available.
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inFieldList bool
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// When visiting group by, groupBy fields are not available.
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inGroupBy bool
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// When visiting having, only fieldList and groupBy fields are available.
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inHaving bool
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// When visiting having, checks if the expr is an aggregate function expr.
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inHavingAgg bool
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// OrderBy clause has different resolving rule than group by.
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inOrderBy bool
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// When visiting column name in ByItem, we should know if the column name is in an expression.
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inByItemExpression bool
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// If subquery use outer context.
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useOuterContext bool
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// When visiting multi-table delete stmt table list.
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inDeleteTableList bool
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// When visiting create/drop table statement.
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inCreateOrDropTable bool
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// When visiting show statement.
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inShow bool
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}
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// currentContext gets the current resolverContext.
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func (nr *nameResolver) currentContext() *resolverContext {
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stackLen := len(nr.contextStack)
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if stackLen == 0 {
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return nil
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}
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return nr.contextStack[stackLen-1]
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}
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// pushContext is called when we enter a statement.
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func (nr *nameResolver) pushContext() {
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nr.contextStack = append(nr.contextStack, &resolverContext{
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tableMap: map[string]int{},
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derivedTableMap: map[string]int{},
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})
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}
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// popContext is called when we leave a statement.
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func (nr *nameResolver) popContext() {
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nr.contextStack = nr.contextStack[:len(nr.contextStack)-1]
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}
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// pushJoin is called when we enter a join node.
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func (nr *nameResolver) pushJoin(j *ast.Join) {
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ctx := nr.currentContext()
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ctx.joinNodeStack = append(ctx.joinNodeStack, j)
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}
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// popJoin is called when we leave a join node.
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func (nr *nameResolver) popJoin() {
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ctx := nr.currentContext()
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ctx.joinNodeStack = ctx.joinNodeStack[:len(ctx.joinNodeStack)-1]
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}
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// Enter implements ast.Visitor interface.
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func (nr *nameResolver) Enter(inNode ast.Node) (outNode ast.Node, skipChildren bool) {
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switch v := inNode.(type) {
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case *ast.AdminStmt:
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nr.pushContext()
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case *ast.AggregateFuncExpr:
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ctx := nr.currentContext()
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if ctx.inHaving {
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ctx.inHavingAgg = true
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}
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case *ast.AlterTableStmt:
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nr.pushContext()
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case *ast.ByItem:
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if _, ok := v.Expr.(*ast.ColumnNameExpr); !ok {
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// If ByItem is not a single column name expression,
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// the resolving rule is different from order by clause.
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nr.currentContext().inByItemExpression = true
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}
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if nr.currentContext().inGroupBy {
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// make sure item is not aggregate function
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if ast.HasAggFlag(v.Expr) {
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nr.Err = ErrInvalidGroupFuncUse
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return inNode, true
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}
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}
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case *ast.CreateIndexStmt:
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nr.pushContext()
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case *ast.CreateTableStmt:
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nr.pushContext()
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nr.currentContext().inCreateOrDropTable = true
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case *ast.DeleteStmt:
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nr.pushContext()
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case *ast.DeleteTableList:
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nr.currentContext().inDeleteTableList = true
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case *ast.DoStmt:
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nr.pushContext()
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case *ast.DropTableStmt:
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nr.pushContext()
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nr.currentContext().inCreateOrDropTable = true
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case *ast.DropIndexStmt:
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nr.pushContext()
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case *ast.FieldList:
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nr.currentContext().inFieldList = true
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case *ast.GroupByClause:
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nr.currentContext().inGroupBy = true
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case *ast.HavingClause:
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nr.currentContext().inHaving = true
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case *ast.InsertStmt:
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nr.pushContext()
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case *ast.Join:
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nr.pushJoin(v)
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case *ast.OnCondition:
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nr.currentContext().inOnCondition = true
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case *ast.OrderByClause:
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nr.currentContext().inOrderBy = true
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case *ast.SelectStmt:
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nr.pushContext()
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case *ast.SetStmt:
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for _, assign := range v.Variables {
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if cn, ok := assign.Value.(*ast.ColumnNameExpr); ok && cn.Name.Table.L == "" {
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// Convert column name expression to string value expression.
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assign.Value = ast.NewValueExpr(cn.Name.Name.O)
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}
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}
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nr.pushContext()
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case *ast.ShowStmt:
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nr.pushContext()
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nr.currentContext().inShow = true
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nr.fillShowFields(v)
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case *ast.TableRefsClause:
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nr.currentContext().inTableRefs = true
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case *ast.TruncateTableStmt:
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nr.pushContext()
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case *ast.UnionStmt:
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nr.pushContext()
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case *ast.UpdateStmt:
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nr.pushContext()
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}
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return inNode, false
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}
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// Leave implements ast.Visitor interface.
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func (nr *nameResolver) Leave(inNode ast.Node) (node ast.Node, ok bool) {
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switch v := inNode.(type) {
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case *ast.AdminStmt:
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nr.popContext()
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case *ast.AggregateFuncExpr:
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ctx := nr.currentContext()
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if ctx.inHaving {
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ctx.inHavingAgg = false
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}
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case *ast.AlterTableStmt:
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nr.popContext()
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case *ast.TableName:
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nr.handleTableName(v)
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case *ast.ColumnNameExpr:
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nr.handleColumnName(v)
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case *ast.CreateIndexStmt:
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nr.popContext()
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case *ast.CreateTableStmt:
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nr.popContext()
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case *ast.DeleteTableList:
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nr.currentContext().inDeleteTableList = false
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case *ast.DoStmt:
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nr.popContext()
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case *ast.DropIndexStmt:
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nr.popContext()
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case *ast.DropTableStmt:
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nr.popContext()
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case *ast.TableSource:
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nr.handleTableSource(v)
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case *ast.OnCondition:
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nr.currentContext().inOnCondition = false
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case *ast.Join:
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nr.handleJoin(v)
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nr.popJoin()
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case *ast.TableRefsClause:
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nr.currentContext().inTableRefs = false
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case *ast.FieldList:
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nr.handleFieldList(v)
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nr.currentContext().inFieldList = false
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case *ast.GroupByClause:
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ctx := nr.currentContext()
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ctx.inGroupBy = false
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for _, item := range v.Items {
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switch x := item.Expr.(type) {
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case *ast.ColumnNameExpr:
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ctx.groupBy = append(ctx.groupBy, x.Refer)
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}
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}
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case *ast.HavingClause:
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nr.currentContext().inHaving = false
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case *ast.OrderByClause:
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nr.currentContext().inOrderBy = false
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case *ast.ByItem:
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nr.currentContext().inByItemExpression = false
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case *ast.PositionExpr:
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nr.handlePosition(v)
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case *ast.SelectStmt:
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ctx := nr.currentContext()
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v.SetResultFields(ctx.fieldList)
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if ctx.useOuterContext {
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nr.useOuterContext = true
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}
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nr.popContext()
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case *ast.SetStmt:
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nr.popContext()
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case *ast.ShowStmt:
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nr.popContext()
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case *ast.SubqueryExpr:
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if nr.useOuterContext {
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// TODO: check this
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// If there is a deep nest of subquery, there may be something wrong.
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v.UseOuterContext = true
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nr.useOuterContext = false
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}
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case *ast.TruncateTableStmt:
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nr.popContext()
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case *ast.UnionStmt:
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ctx := nr.currentContext()
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v.SetResultFields(ctx.fieldList)
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if ctx.useOuterContext {
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nr.useOuterContext = true
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}
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nr.popContext()
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case *ast.UnionSelectList:
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nr.handleUnionSelectList(v)
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case *ast.InsertStmt:
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nr.popContext()
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case *ast.DeleteStmt:
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nr.popContext()
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case *ast.UpdateStmt:
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nr.popContext()
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}
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return inNode, nr.Err == nil
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}
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// handleTableName looks up and sets the schema information and result fields for table name.
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func (nr *nameResolver) handleTableName(tn *ast.TableName) {
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if tn.Schema.L == "" {
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tn.Schema = nr.DefaultSchema
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}
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ctx := nr.currentContext()
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if ctx.inCreateOrDropTable {
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// The table may not exist in create table or drop table statement.
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// Skip resolving the table to avoid error.
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return
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}
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if ctx.inDeleteTableList {
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idx, ok := ctx.tableMap[nr.tableUniqueName(tn.Schema, tn.Name)]
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if !ok {
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nr.Err = errors.Errorf("Unknown table %s", tn.Name.O)
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return
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}
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ts := ctx.tables[idx]
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tableName := ts.Source.(*ast.TableName)
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tn.DBInfo = tableName.DBInfo
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tn.TableInfo = tableName.TableInfo
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tn.SetResultFields(tableName.GetResultFields())
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return
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}
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table, err := nr.Info.TableByName(tn.Schema, tn.Name)
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if err != nil {
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nr.Err = errors.Trace(err)
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return
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}
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tn.TableInfo = table.Meta()
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dbInfo, _ := nr.Info.SchemaByName(tn.Schema)
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tn.DBInfo = dbInfo
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rfs := make([]*ast.ResultField, 0, len(tn.TableInfo.Columns))
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for _, v := range tn.TableInfo.Columns {
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if v.State != model.StatePublic {
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continue
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}
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expr := &ast.ValueExpr{}
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expr.SetType(&v.FieldType)
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rf := &ast.ResultField{
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Column: v,
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Table: tn.TableInfo,
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DBName: tn.Schema,
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Expr: expr,
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TableName: tn,
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}
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rfs = append(rfs, rf)
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}
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tn.SetResultFields(rfs)
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return
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}
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// handleTableSources checks name duplication
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// and puts the table source in current resolverContext.
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// Note:
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// "select * from t as a join (select 1) as a;" is not duplicate.
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// "select * from t as a join t as a;" is duplicate.
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// "select * from (select 1) as a join (select 1) as a;" is duplicate.
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func (nr *nameResolver) handleTableSource(ts *ast.TableSource) {
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for _, v := range ts.GetResultFields() {
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v.TableAsName = ts.AsName
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}
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ctx := nr.currentContext()
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switch ts.Source.(type) {
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case *ast.TableName:
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var name string
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if ts.AsName.L != "" {
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name = ts.AsName.L
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} else {
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tableName := ts.Source.(*ast.TableName)
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name = nr.tableUniqueName(tableName.Schema, tableName.Name)
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}
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if _, ok := ctx.tableMap[name]; ok {
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nr.Err = errors.Errorf("duplicated table/alias name %s", name)
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return
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}
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ctx.tableMap[name] = len(ctx.tables)
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case *ast.SelectStmt:
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name := ts.AsName.L
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if _, ok := ctx.derivedTableMap[name]; ok {
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nr.Err = errors.Errorf("duplicated table/alias name %s", name)
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return
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}
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ctx.derivedTableMap[name] = len(ctx.tables)
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}
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dupNames := make(map[string]struct{}, len(ts.GetResultFields()))
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for _, f := range ts.GetResultFields() {
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// duplicate column name in one table is not allowed.
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// "select * from (select 1, 1) as a;" is duplicate.
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name := f.ColumnAsName.L
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if name == "" {
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name = f.Column.Name.L
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}
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if _, ok := dupNames[name]; ok {
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nr.Err = errors.Errorf("Duplicate column name '%s'", name)
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return
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}
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dupNames[name] = struct{}{}
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}
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ctx.tables = append(ctx.tables, ts)
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return
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}
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// handleJoin sets result fields for join.
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func (nr *nameResolver) handleJoin(j *ast.Join) {
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if j.Right == nil {
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j.SetResultFields(j.Left.GetResultFields())
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return
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}
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leftLen := len(j.Left.GetResultFields())
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rightLen := len(j.Right.GetResultFields())
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rfs := make([]*ast.ResultField, leftLen+rightLen)
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copy(rfs, j.Left.GetResultFields())
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copy(rfs[leftLen:], j.Right.GetResultFields())
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j.SetResultFields(rfs)
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}
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// handleColumnName looks up and sets ResultField for
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// the column name.
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func (nr *nameResolver) handleColumnName(cn *ast.ColumnNameExpr) {
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ctx := nr.currentContext()
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if ctx.inOnCondition {
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// In on condition, only tables within current join is available.
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nr.resolveColumnNameInOnCondition(cn)
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return
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}
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// Try to resolve the column name form top to bottom in the context stack.
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for i := len(nr.contextStack) - 1; i >= 0; i-- {
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if nr.resolveColumnNameInContext(nr.contextStack[i], cn) {
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// Column is already resolved or encountered an error.
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if i < len(nr.contextStack)-1 {
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// If in subselect, the query use outer query.
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nr.currentContext().useOuterContext = true
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}
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return
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}
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}
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nr.Err = errors.Errorf("unknown column %s", cn.Name.Name.L)
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}
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// resolveColumnNameInContext looks up and sets ResultField for a column with the ctx.
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func (nr *nameResolver) resolveColumnNameInContext(ctx *resolverContext, cn *ast.ColumnNameExpr) bool {
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if ctx.inTableRefs {
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// In TableRefsClause, column reference only in join on condition which is handled before.
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return false
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}
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if ctx.inFieldList {
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// only resolve column using tables.
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return nr.resolveColumnInTableSources(cn, ctx.tables)
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}
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if ctx.inGroupBy {
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// From tables first, then field list.
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// If ctx.InByItemExpression is true, the item is not an identifier.
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// Otherwise it is an identifier.
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if ctx.inByItemExpression {
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// From table first, then field list.
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if nr.resolveColumnInTableSources(cn, ctx.tables) {
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return true
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}
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found := nr.resolveColumnInResultFields(ctx, cn, ctx.fieldList)
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if nr.Err == nil && found {
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// Check if resolved refer is an aggregate function expr.
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if _, ok := cn.Refer.Expr.(*ast.AggregateFuncExpr); ok {
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nr.Err = ErrIllegalReference.Gen("Reference '%s' not supported (reference to group function)", cn.Name.Name.O)
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}
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}
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return found
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}
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// Resolve from table first, then from select list.
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found := nr.resolveColumnInTableSources(cn, ctx.tables)
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if nr.Err != nil {
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return found
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}
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// We should copy the refer here.
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// Because if the ByItem is an identifier, we should check if it
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// is ambiguous even it is already resolved from table source.
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// If the ByItem is not an identifier, we do not need the second check.
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r := cn.Refer
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if nr.resolveColumnInResultFields(ctx, cn, ctx.fieldList) {
|
|
if nr.Err != nil {
|
|
return true
|
|
}
|
|
if r != nil {
|
|
// It is not ambiguous and already resolved from table source.
|
|
// We should restore its Refer.
|
|
cn.Refer = r
|
|
}
|
|
if _, ok := cn.Refer.Expr.(*ast.AggregateFuncExpr); ok {
|
|
nr.Err = ErrIllegalReference.Gen("Reference '%s' not supported (reference to group function)", cn.Name.Name.O)
|
|
}
|
|
return true
|
|
}
|
|
return found
|
|
}
|
|
if ctx.inHaving {
|
|
// First group by, then field list.
|
|
if nr.resolveColumnInResultFields(ctx, cn, ctx.groupBy) {
|
|
return true
|
|
}
|
|
if ctx.inHavingAgg {
|
|
// If cn is in an aggregate function in having clause, check tablesource first.
|
|
if nr.resolveColumnInTableSources(cn, ctx.tables) {
|
|
return true
|
|
}
|
|
}
|
|
return nr.resolveColumnInResultFields(ctx, cn, ctx.fieldList)
|
|
}
|
|
if ctx.inOrderBy {
|
|
if nr.resolveColumnInResultFields(ctx, cn, ctx.groupBy) {
|
|
return true
|
|
}
|
|
if ctx.inByItemExpression {
|
|
// From table first, then field list.
|
|
if nr.resolveColumnInTableSources(cn, ctx.tables) {
|
|
return true
|
|
}
|
|
return nr.resolveColumnInResultFields(ctx, cn, ctx.fieldList)
|
|
}
|
|
// Field list first, then from table.
|
|
if nr.resolveColumnInResultFields(ctx, cn, ctx.fieldList) {
|
|
return true
|
|
}
|
|
return nr.resolveColumnInTableSources(cn, ctx.tables)
|
|
}
|
|
if ctx.inShow {
|
|
return nr.resolveColumnInResultFields(ctx, cn, ctx.fieldList)
|
|
}
|
|
// In where clause.
|
|
return nr.resolveColumnInTableSources(cn, ctx.tables)
|
|
}
|
|
|
|
// resolveColumnNameInOnCondition resolves the column name in current join.
|
|
func (nr *nameResolver) resolveColumnNameInOnCondition(cn *ast.ColumnNameExpr) {
|
|
ctx := nr.currentContext()
|
|
join := ctx.joinNodeStack[len(ctx.joinNodeStack)-1]
|
|
tableSources := appendTableSources(nil, join)
|
|
if !nr.resolveColumnInTableSources(cn, tableSources) {
|
|
nr.Err = errors.Errorf("unkown column name %s", cn.Name.Name.O)
|
|
}
|
|
}
|
|
|
|
func (nr *nameResolver) resolveColumnInTableSources(cn *ast.ColumnNameExpr, tableSources []*ast.TableSource) (done bool) {
|
|
var matchedResultField *ast.ResultField
|
|
tableNameL := cn.Name.Table.L
|
|
columnNameL := cn.Name.Name.L
|
|
if tableNameL != "" {
|
|
var matchedTable ast.ResultSetNode
|
|
for _, ts := range tableSources {
|
|
if tableNameL == ts.AsName.L {
|
|
// different table name.
|
|
matchedTable = ts
|
|
break
|
|
} else if ts.AsName.L != "" {
|
|
// Table as name shadows table real name.
|
|
continue
|
|
}
|
|
if tn, ok := ts.Source.(*ast.TableName); ok {
|
|
if cn.Name.Schema.L != "" && cn.Name.Schema.L != tn.Schema.L {
|
|
continue
|
|
}
|
|
if tableNameL == tn.Name.L {
|
|
matchedTable = ts
|
|
}
|
|
}
|
|
}
|
|
if matchedTable != nil {
|
|
resultFields := matchedTable.GetResultFields()
|
|
for _, rf := range resultFields {
|
|
if rf.ColumnAsName.L == columnNameL || rf.Column.Name.L == columnNameL {
|
|
// resolve column.
|
|
matchedResultField = rf
|
|
break
|
|
}
|
|
}
|
|
}
|
|
} else {
|
|
for _, ts := range tableSources {
|
|
rfs := ts.GetResultFields()
|
|
for _, rf := range rfs {
|
|
matchAsName := rf.ColumnAsName.L != "" && rf.ColumnAsName.L == columnNameL
|
|
matchColumnName := rf.ColumnAsName.L == "" && rf.Column.Name.L == columnNameL
|
|
if matchAsName || matchColumnName {
|
|
if matchedResultField != nil {
|
|
nr.Err = errors.Errorf("column %s is ambiguous.", cn.Name.Name.O)
|
|
return true
|
|
}
|
|
matchedResultField = rf
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if matchedResultField != nil {
|
|
// Bind column.
|
|
cn.Refer = matchedResultField
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
func (nr *nameResolver) resolveColumnInResultFields(ctx *resolverContext, cn *ast.ColumnNameExpr, rfs []*ast.ResultField) bool {
|
|
var matched *ast.ResultField
|
|
for _, rf := range rfs {
|
|
if cn.Name.Table.L != "" {
|
|
// Check table name
|
|
if rf.TableAsName.L != "" {
|
|
if cn.Name.Table.L != rf.TableAsName.L {
|
|
continue
|
|
}
|
|
} else if cn.Name.Table.L != rf.Table.Name.L {
|
|
continue
|
|
}
|
|
}
|
|
matchAsName := cn.Name.Name.L == rf.ColumnAsName.L
|
|
var matchColumnName bool
|
|
if ctx.inHaving {
|
|
matchColumnName = cn.Name.Name.L == rf.Column.Name.L
|
|
} else {
|
|
matchColumnName = rf.ColumnAsName.L == "" && cn.Name.Name.L == rf.Column.Name.L
|
|
}
|
|
if matchAsName || matchColumnName {
|
|
if rf.Column.Name.L == "" {
|
|
// This is not a real table column, resolve it directly.
|
|
cn.Refer = rf
|
|
return true
|
|
}
|
|
if matched == nil {
|
|
matched = rf
|
|
} else {
|
|
sameColumn := matched.TableName == rf.TableName && matched.Column.Name.L == rf.Column.Name.L
|
|
if !sameColumn {
|
|
nr.Err = errors.Errorf("column %s is ambiguous.", cn.Name.Name.O)
|
|
return true
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if matched != nil {
|
|
// If in GroupBy, we clone the ResultField
|
|
if ctx.inGroupBy || ctx.inHaving || ctx.inOrderBy {
|
|
nf := *matched
|
|
expr := matched.Expr
|
|
if cexpr, ok := expr.(*ast.ColumnNameExpr); ok {
|
|
expr = cexpr.Refer.Expr
|
|
}
|
|
nf.Expr = expr
|
|
matched = &nf
|
|
}
|
|
// Bind column.
|
|
cn.Refer = matched
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
// handleFieldList expands wild card field and sets fieldList in current context.
|
|
func (nr *nameResolver) handleFieldList(fieldList *ast.FieldList) {
|
|
var resultFields []*ast.ResultField
|
|
for _, v := range fieldList.Fields {
|
|
resultFields = append(resultFields, nr.createResultFields(v)...)
|
|
}
|
|
nr.currentContext().fieldList = resultFields
|
|
}
|
|
|
|
func getInnerFromParentheses(expr ast.ExprNode) ast.ExprNode {
|
|
if pexpr, ok := expr.(*ast.ParenthesesExpr); ok {
|
|
return getInnerFromParentheses(pexpr.Expr)
|
|
}
|
|
return expr
|
|
}
|
|
|
|
// createResultFields creates result field list for a single select field.
|
|
func (nr *nameResolver) createResultFields(field *ast.SelectField) (rfs []*ast.ResultField) {
|
|
ctx := nr.currentContext()
|
|
if field.WildCard != nil {
|
|
if len(ctx.tables) == 0 {
|
|
nr.Err = errors.New("No table used.")
|
|
return
|
|
}
|
|
tableRfs := []*ast.ResultField{}
|
|
if field.WildCard.Table.L == "" {
|
|
for _, v := range ctx.tables {
|
|
tableRfs = append(tableRfs, v.GetResultFields()...)
|
|
}
|
|
} else {
|
|
name := nr.tableUniqueName(field.WildCard.Schema, field.WildCard.Table)
|
|
tableIdx, ok1 := ctx.tableMap[name]
|
|
derivedTableIdx, ok2 := ctx.derivedTableMap[name]
|
|
if !ok1 && !ok2 {
|
|
nr.Err = errors.Errorf("unknown table %s.", field.WildCard.Table.O)
|
|
}
|
|
if ok1 {
|
|
tableRfs = ctx.tables[tableIdx].GetResultFields()
|
|
}
|
|
if ok2 {
|
|
tableRfs = append(tableRfs, ctx.tables[derivedTableIdx].GetResultFields()...)
|
|
}
|
|
|
|
}
|
|
for _, trf := range tableRfs {
|
|
// Convert it to ColumnNameExpr
|
|
cn := &ast.ColumnName{
|
|
Schema: trf.DBName,
|
|
Table: trf.Table.Name,
|
|
Name: trf.ColumnAsName,
|
|
}
|
|
cnExpr := &ast.ColumnNameExpr{
|
|
Name: cn,
|
|
Refer: trf,
|
|
}
|
|
ast.SetFlag(cnExpr)
|
|
cnExpr.SetType(trf.Expr.GetType())
|
|
rf := *trf
|
|
rf.Expr = cnExpr
|
|
rfs = append(rfs, &rf)
|
|
}
|
|
return
|
|
}
|
|
// The column is visited before so it must has been resolved already.
|
|
rf := &ast.ResultField{ColumnAsName: field.AsName}
|
|
innerExpr := getInnerFromParentheses(field.Expr)
|
|
switch v := innerExpr.(type) {
|
|
case *ast.ColumnNameExpr:
|
|
rf.Column = v.Refer.Column
|
|
rf.Table = v.Refer.Table
|
|
rf.DBName = v.Refer.DBName
|
|
rf.TableName = v.Refer.TableName
|
|
rf.Expr = v
|
|
default:
|
|
rf.Column = &model.ColumnInfo{} // Empty column info.
|
|
rf.Table = &model.TableInfo{} // Empty table info.
|
|
rf.Expr = v
|
|
}
|
|
if field.AsName.L == "" {
|
|
switch x := innerExpr.(type) {
|
|
case *ast.ColumnNameExpr:
|
|
rf.ColumnAsName = model.NewCIStr(x.Name.Name.O)
|
|
case *ast.ValueExpr:
|
|
if innerExpr.Text() != "" {
|
|
rf.ColumnAsName = model.NewCIStr(innerExpr.Text())
|
|
} else {
|
|
rf.ColumnAsName = model.NewCIStr(field.Text())
|
|
}
|
|
default:
|
|
rf.ColumnAsName = model.NewCIStr(field.Text())
|
|
}
|
|
}
|
|
rfs = append(rfs, rf)
|
|
return
|
|
}
|
|
|
|
func appendTableSources(in []*ast.TableSource, resultSetNode ast.ResultSetNode) (out []*ast.TableSource) {
|
|
switch v := resultSetNode.(type) {
|
|
case *ast.TableSource:
|
|
out = append(in, v)
|
|
case *ast.Join:
|
|
out = appendTableSources(in, v.Left)
|
|
if v.Right != nil {
|
|
out = appendTableSources(out, v.Right)
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
func (nr *nameResolver) tableUniqueName(schema, table model.CIStr) string {
|
|
if schema.L != "" && schema.L != nr.DefaultSchema.L {
|
|
return schema.L + "." + table.L
|
|
}
|
|
return table.L
|
|
}
|
|
|
|
func (nr *nameResolver) handlePosition(pos *ast.PositionExpr) {
|
|
ctx := nr.currentContext()
|
|
if pos.N < 1 || pos.N > len(ctx.fieldList) {
|
|
nr.Err = errors.Errorf("Unknown column '%d'", pos.N)
|
|
return
|
|
}
|
|
matched := ctx.fieldList[pos.N-1]
|
|
nf := *matched
|
|
expr := matched.Expr
|
|
if cexpr, ok := expr.(*ast.ColumnNameExpr); ok {
|
|
expr = cexpr.Refer.Expr
|
|
}
|
|
nf.Expr = expr
|
|
pos.Refer = &nf
|
|
if nr.currentContext().inGroupBy {
|
|
// make sure item is not aggregate function
|
|
if ast.HasAggFlag(pos.Refer.Expr) {
|
|
nr.Err = errors.New("group by cannot contain aggregate function")
|
|
}
|
|
}
|
|
}
|
|
|
|
func (nr *nameResolver) handleUnionSelectList(u *ast.UnionSelectList) {
|
|
firstSelFields := u.Selects[0].GetResultFields()
|
|
unionFields := make([]*ast.ResultField, len(firstSelFields))
|
|
// Copy first result fields, because we may change the result field type.
|
|
for i, v := range firstSelFields {
|
|
rf := *v
|
|
col := *v.Column
|
|
rf.Column = &col
|
|
if rf.Column.Flen == 0 {
|
|
rf.Column.Flen = types.UnspecifiedLength
|
|
}
|
|
rf.Expr = &ast.ValueExpr{}
|
|
unionFields[i] = &rf
|
|
}
|
|
nr.currentContext().fieldList = unionFields
|
|
}
|
|
|
|
func (nr *nameResolver) fillShowFields(s *ast.ShowStmt) {
|
|
if s.DBName == "" {
|
|
if s.Table != nil && s.Table.Schema.L != "" {
|
|
s.DBName = s.Table.Schema.O
|
|
} else {
|
|
s.DBName = nr.DefaultSchema.O
|
|
}
|
|
} else if s.Table != nil && s.Table.Schema.L == "" {
|
|
s.Table.Schema = model.NewCIStr(s.DBName)
|
|
}
|
|
var fields []*ast.ResultField
|
|
var (
|
|
names []string
|
|
ftypes []byte
|
|
)
|
|
switch s.Tp {
|
|
case ast.ShowEngines:
|
|
names = []string{"Engine", "Support", "Comment", "Transactions", "XA", "Savepoints"}
|
|
case ast.ShowDatabases:
|
|
names = []string{"Database"}
|
|
case ast.ShowTables:
|
|
names = []string{fmt.Sprintf("Tables_in_%s", s.DBName)}
|
|
if s.Full {
|
|
names = append(names, "Table_type")
|
|
}
|
|
case ast.ShowTableStatus:
|
|
names = []string{"Name", "Engine", "Version", "Row_format", "Rows", "Avg_row_length",
|
|
"Data_length", "Max_data_length", "Index_length", "Data_free", "Auto_increment",
|
|
"Create_time", "Update_time", "Check_time", "Collation", "Checksum",
|
|
"Create_options", "Comment"}
|
|
ftypes = []byte{mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeLonglong, mysql.TypeVarchar, mysql.TypeLonglong, mysql.TypeLonglong,
|
|
mysql.TypeLonglong, mysql.TypeLonglong, mysql.TypeLonglong, mysql.TypeLonglong, mysql.TypeLonglong,
|
|
mysql.TypeDatetime, mysql.TypeDatetime, mysql.TypeDatetime, mysql.TypeVarchar, mysql.TypeVarchar,
|
|
mysql.TypeVarchar, mysql.TypeVarchar}
|
|
case ast.ShowColumns:
|
|
names = column.ColDescFieldNames(s.Full)
|
|
case ast.ShowWarnings:
|
|
names = []string{"Level", "Code", "Message"}
|
|
ftypes = []byte{mysql.TypeVarchar, mysql.TypeLong, mysql.TypeVarchar}
|
|
case ast.ShowCharset:
|
|
names = []string{"Charset", "Description", "Default collation", "Maxlen"}
|
|
ftypes = []byte{mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeLonglong}
|
|
case ast.ShowVariables:
|
|
names = []string{"Variable_name", "Value"}
|
|
case ast.ShowStatus:
|
|
names = []string{"Variable_name", "Value"}
|
|
case ast.ShowCollation:
|
|
names = []string{"Collation", "Charset", "Id", "Default", "Compiled", "Sortlen"}
|
|
ftypes = []byte{mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeLonglong,
|
|
mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeLonglong}
|
|
case ast.ShowCreateTable:
|
|
names = []string{"Table", "Create Table"}
|
|
case ast.ShowGrants:
|
|
names = []string{fmt.Sprintf("Grants for %s", s.User)}
|
|
case ast.ShowTriggers:
|
|
names = []string{"Trigger", "Event", "Table", "Statement", "Timing", "Created",
|
|
"sql_mode", "Definer", "character_set_client", "collation_connection", "Database Collation"}
|
|
ftypes = []byte{mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar,
|
|
mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar}
|
|
case ast.ShowProcedureStatus:
|
|
names = []string{}
|
|
ftypes = []byte{}
|
|
case ast.ShowIndex:
|
|
names = []string{"Table", "Non_unique", "Key_name", "Seq_in_index",
|
|
"Column_name", "Collation", "Cardinality", "Sub_part", "Packed",
|
|
"Null", "Index_type", "Comment", "Index_comment"}
|
|
ftypes = []byte{mysql.TypeVarchar, mysql.TypeLonglong, mysql.TypeVarchar, mysql.TypeLonglong,
|
|
mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeLonglong, mysql.TypeLonglong,
|
|
mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar, mysql.TypeVarchar}
|
|
}
|
|
for i, name := range names {
|
|
f := &ast.ResultField{
|
|
ColumnAsName: model.NewCIStr(name),
|
|
Column: &model.ColumnInfo{}, // Empty column info.
|
|
Table: &model.TableInfo{}, // Empty table info.
|
|
}
|
|
if ftypes == nil || ftypes[i] == 0 {
|
|
// use varchar as the default return column type
|
|
f.Column.Tp = mysql.TypeVarchar
|
|
} else {
|
|
f.Column.Tp = ftypes[i]
|
|
}
|
|
f.Column.Charset, f.Column.Collate = types.DefaultCharsetForType(f.Column.Tp)
|
|
f.Expr = &ast.ValueExpr{}
|
|
f.Expr.SetType(&f.Column.FieldType)
|
|
fields = append(fields, f)
|
|
}
|
|
|
|
if s.Pattern != nil && s.Pattern.Expr == nil {
|
|
rf := fields[0]
|
|
s.Pattern.Expr = &ast.ColumnNameExpr{
|
|
Name: &ast.ColumnName{Name: rf.ColumnAsName},
|
|
}
|
|
ast.SetFlag(s.Pattern)
|
|
}
|
|
s.SetResultFields(fields)
|
|
nr.currentContext().fieldList = fields
|
|
}
|