/**
* Copyright 2011-2013 Akiban Technologies, 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,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* The original from which this derives bore the following: */
/*
Derby - Class org.apache.derby.impl.sql.compile.SelectNode
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to you 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,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package com.akiban.sql.parser;
import com.akiban.sql.StandardException;
import java.util.List;
/**
* A SelectNode represents the result set for any of the basic DML
* operations: SELECT, INSERT, UPDATE, and DELETE. (A RowResultSetNode
* will be used for an INSERT with a VALUES clause.) For INSERT - SELECT,
* any of the fields in a SelectNode can be used (the SelectNode represents
* the SELECT statement in the INSERT - SELECT). For UPDATE and
* DELETE, there will be one table in the fromList, and the groupByList
* fields will be null. For both INSERT and UPDATE,
* the resultColumns in the selectList will contain the names of the columns
* being inserted into or updated.
*
*/
public class SelectNode extends ResultSetNode
{
/**
* List of tables in the FROM clause of this SELECT
*/
private FromList fromList;
/**
* The ValueNode for the WHERE clause must represent a boolean
* expression. The binding phase will enforce this - the parser
* does not have enough information to enforce it in all cases
* (for example, user methods that return boolean).
*/
private ValueNode whereClause;
/**
* List of result columns in GROUP BY clause
*/
private GroupByList groupByList;
/**
* List of windows.
*/
private WindowList windows;
private boolean isDistinct, isStraightJoin;
private ValueNode havingClause;
public void init(Object selectList,
Object aggregateList,
Object fromList,
Object whereClause,
Object groupByList,
Object havingClause,
Object windowDefinitionList)
throws StandardException {
/* RESOLVE - remove aggregateList from constructor.
* Consider adding selectAggregates and whereAggregates
*/
resultColumns = (ResultColumnList)selectList;
if (resultColumns != null)
resultColumns.markInitialSize();
this.fromList = (FromList)fromList;
this.whereClause = (ValueNode)whereClause;
this.groupByList = (GroupByList)groupByList;
this.havingClause = (ValueNode)havingClause;
// This initially represents an explicit <window definition list>, as
// opposed to <in-line window specifications>, see 2003, 6.10 and 6.11.
// <in-line window specifications> are added later, see right below for
// in-line window specifications used in window functions in the SELECT
// column list and in genProjectRestrict for such window specifications
// used in window functions in ORDER BY.
this.windows = (WindowList)windowDefinitionList;
// TODO: Walking to find window and subqueries in WHERE.
}
/**
* Fill this node with a deep copy of the given node.
*/
public void copyFrom(QueryTreeNode node) throws StandardException {
super.copyFrom(node);
SelectNode other = (SelectNode)node;
this.fromList = (FromList)getNodeFactory().copyNode(other.fromList,
getParserContext());
this.whereClause = (ValueNode)getNodeFactory().copyNode(other.whereClause,
getParserContext());
this.groupByList = (GroupByList)getNodeFactory().copyNode(other.groupByList,
getParserContext());
this.windows = (WindowList)getNodeFactory().copyNode(other.windows,
getParserContext());
this.isDistinct = other.isDistinct;
this.havingClause = (ValueNode)getNodeFactory().copyNode(other.havingClause,
getParserContext());
}
/**
* Convert this object to a String. See comments in QueryTreeNode.java
* for how this should be done for tree printing.
*
* @return This object as a String
*/
public String toString() {
return "isDistinct: "+ isDistinct + "\n"+
super.toString();
}
public String statementToString() {
return "SELECT";
}
public void makeDistinct() {
isDistinct = true;
}
public void clearDistinct() {
isDistinct = false;
}
public boolean isDistinct() {
return isDistinct;
}
public void makeStraightJoin() {
isStraightJoin = true;
}
public boolean isStraightJoin() {
return isStraightJoin;
}
/**
* Prints the sub-nodes of this object. See QueryTreeNode.java for
* how tree printing is supposed to work.
*
* @param depth The depth of this node in the tree
*/
public void printSubNodes(int depth) {
super.printSubNodes(depth);
printLabel(depth, "fromList: ");
if (fromList != null) {
fromList.treePrint(depth + 1);
}
if (whereClause != null) {
printLabel(depth, "whereClause: ");
whereClause.treePrint(depth + 1);
}
if (groupByList != null) {
printLabel(depth, "groupByList:");
groupByList.treePrint(depth + 1);
}
if (havingClause != null) {
printLabel(depth, "havingClause:");
havingClause.treePrint(depth + 1);
}
if (windows != null) {
printLabel(depth, "windows: ");
windows.treePrint(depth + 1);
}
}
/**
* Return the fromList for this SelectNode.
*
* @return FromList The fromList for this SelectNode.
*/
public FromList getFromList() {
return fromList;
}
/**
* Return the whereClause for this SelectNode.
*
* @return ValueNode The whereClause for this SelectNode.
*/
public ValueNode getWhereClause() {
return whereClause;
}
public void setWhereClause(ValueNode whereClause) {
this.whereClause = whereClause;
}
public GroupByList getGroupByList() {
return groupByList;
}
public ValueNode getHavingClause() {
return havingClause;
}
public void setHavingClause(ValueNode havingClause) {
this.havingClause = havingClause;
}
/**
* Accept the visitor for all visitable children of this node.
*
* @param v the visitor
*
* @exception StandardException on error
*/
void acceptChildren(Visitor v) throws StandardException {
super.acceptChildren(v);
if (fromList != null) {
fromList = (FromList)fromList.accept(v);
}
if (whereClause != null) {
whereClause = (ValueNode)whereClause.accept(v);
}
if (groupByList != null) {
groupByList = (GroupByList)groupByList.accept(v);
}
if (havingClause != null) {
havingClause = (ValueNode)havingClause.accept(v);
}
if (windows != null) {
windows = (WindowList)windows.accept(v);
}
}
/**
* Used by SubqueryNode to avoid flattening of a subquery if a window is
* defined on it. Note that any inline window definitions should have been
* collected from both the selectList and orderByList at the time this
* method is called, so the windows list is complete. This is true after
* preprocess is completed.
*
* @return true if this select node has any windows on it
*/
public boolean hasWindows() {
return windows != null;
}
public WindowList getWindows() {
return windows;
}
}