package com.taobao.tddl.optimizer.core.ast.build;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;
import com.taobao.tddl.optimizer.core.ASTNodeFactory;
import com.taobao.tddl.optimizer.core.ast.ASTNode;
import com.taobao.tddl.optimizer.core.ast.QueryTreeNode;
import com.taobao.tddl.optimizer.core.ast.query.JoinNode;
import com.taobao.tddl.optimizer.core.expression.IBooleanFilter;
import com.taobao.tddl.optimizer.core.expression.IColumn;
import com.taobao.tddl.optimizer.core.expression.IFilter;
import com.taobao.tddl.optimizer.core.expression.IFunction;
import com.taobao.tddl.optimizer.core.expression.ISelectable;
import com.taobao.tddl.optimizer.utils.FilterUtils;
/**
* @since 5.0.0
*/
public class JoinNodeBuilder extends QueryTreeNodeBuilder {
private Set<IColumn> columnInAggregate = new HashSet();
public JoinNodeBuilder(JoinNode joinNode){
this.setNode(joinNode);
}
public JoinNode getNode() {
return (JoinNode) super.getNode();
}
public void build() {
if (this.getNode().isUedForIndexJoinPK()) {
return;
}
this.columnInAggregate.clear();
this.buildSelected();
this.buildJoinKeys();
this.buildWhere();
this.buildGroupBy();
this.buildOrderBy();
this.buildHaving();
this.buildColumnRefered();
this.buildExistAggregate();
}
private void buildColumnRefered() {
List<ISelectable> columnRefered = new ArrayList();
columnRefered.addAll(this.getNode().getColumnsSelected());
for (IBooleanFilter f : this.getNode().getJoinFilter()) {
ISelectable left = (ISelectable) f.getColumn();
ISelectable right = (ISelectable) f.getValue();
if (!columnRefered.contains(left)) {
columnRefered.add(left);
}
if (!columnRefered.contains(right)) {
columnRefered.add(right);
}
}
for (IColumn c : this.columnInAggregate) {
if (!columnRefered.contains(c)) {
columnRefered.add(c);
}
}
this.getNode().setColumnsRefered(columnRefered);
}
private void buildJoinKeys() {
if (this.getNode().isUedForIndexJoinPK()) {
return;
}
List<IBooleanFilter> otherJoinOnFilters = new ArrayList(this.getNode().getJoinFilter().size());
for (IBooleanFilter f : this.getNode().getJoinFilter()) {
ISelectable leftKey = null;
if (f.getColumn() != null && f.getColumn() instanceof ISelectable) {
leftKey = this.getColumnFromOtherNode((ISelectable) f.getColumn(), this.getNode().getLeftNode());
}
ISelectable rightKey = null;
if (f.getValue() != null && f.getValue() instanceof ISelectable) {
rightKey = this.getColumnFromOtherNode((ISelectable) f.getValue(), this.getNode().getRightNode());
}
// 可能顺序调换了，重新找一次
if (leftKey == null || rightKey == null) {
if (f.getValue() != null && f.getValue() instanceof ISelectable) {
leftKey = this.getColumnFromOtherNode((ISelectable) f.getValue(), this.getNode().getLeftNode());
}
if (f.getColumn() != null && f.getColumn() instanceof ISelectable) {
rightKey = this.getColumnFromOtherNode((ISelectable) f.getColumn(), this.getNode().getRightNode());
}
}
if (leftKey == null || rightKey == null) {
// 可能有以下情况
// id=1,s.id=s.key_id
IFilter otherJoinOnFilter = this.getNode().getOtherJoinOnFilter();
otherJoinOnFilter = FilterUtils.and(otherJoinOnFilter, f);
this.getNode().setOtherJoinOnFilter(otherJoinOnFilter);
otherJoinOnFilters.add(f);
continue;
}
/**
* 如果是回表操作，不能把索引的joinKey添加到temp中，否则如果有merge，这个列会被加到sql的select中，
* 而导致找不到列
*/
if (!this.getNode().isUedForIndexJoinPK()) {
f.setColumn(buildSelectable(leftKey));
f.setValue(buildSelectable(rightKey));
}
}
this.getNode().getJoinFilter().removeAll(otherJoinOnFilters);
this.buildFilter(this.getNode().getOtherJoinOnFilter(), false);
}
/**
* 构建列信息
*
* @param indexNode
*/
public void buildSelected() {
buildSelectedFromSelectableObject();
}
private void buildSelectedFromSelectableObject() {
// 如果为空，代表是用*
if (this.getNode().getColumnsSelected().isEmpty()) {
this.getNode()
.getColumnsSelected()
.add(ASTNodeFactory.getInstance().createColumn().setColumnName(IColumn.STAR));
}
// 如果有 * ，最后需要把*删掉
List<Integer> delete = new LinkedList();
int index = 0;
for (ISelectable selected : getNode().getColumnsSelected()) {
if (IColumn.STAR.equals(selected.getColumnName())) {
delete.add(index);
break;
}
}
if (!delete.isEmpty()) {
List<ISelectable> columnsWithOutStar = new ArrayList();
for (int i = 0; i < this.getNode().getColumnsSelected().size(); i++) {
ISelectable selected = this.getNode().getColumnsSelected().get(i);
if (this.getNode().getColumnsSelected().get(i).getColumnName().equals(IColumn.STAR)) {
// 遇到*就把所有列再添加一遍
// select *,id这样的语法最后会有两个id列，mysql是这样的
for (ASTNode child : this.getNode().getChildren()) {
for (ISelectable selectedFromChild : ((QueryTreeNode) child).getColumnsSelectedForParent()) {
// 考虑
// a. SELECT B.* FROM TABLE1 A INNER JOIN TABLE2 B
// b. SELECT * FROM TABLE1 A INNER JOIN TABLE2 B
if (selected.getTableName() != null
&& !selected.getTableName().equals(selectedFromChild.getTableName())) {
break;
}
IColumn newS = ASTNodeFactory.getInstance().createColumn();
// 尝试复制子节点的表别名
if (((QueryTreeNode) child).getAlias() != null) {
newS.setTableName(((QueryTreeNode) child).getAlias());
} else {
newS.setTableName(selectedFromChild.getTableName());
}
if (selectedFromChild.getAlias() != null) {
newS.setColumnName(selectedFromChild.getAlias());
} else {
newS.setColumnName(selectedFromChild.getColumnName());
}
columnsWithOutStar.add(newS);
}
}
} else {
columnsWithOutStar.add(this.getNode().getColumnsSelected().get(i));
}
}
this.getNode().select(columnsWithOutStar);
}
for (int i = 0; i < getNode().getColumnsSelected().size(); i++) {
getNode().getColumnsSelected().set(i, this.buildSelectable(getNode().getColumnsSelected().get(i)));
}
}
public ISelectable getSelectableFromChild(ISelectable c) {
if (c instanceof IFunction) {
return c;
}
if (IColumn.STAR.equals(c.getColumnName())) {
return c;
}
QueryTreeNode left = this.getNode().getLeftNode();
QueryTreeNode right = this.getNode().getRightNode();
ISelectable resFromLeft = null;
ISelectable resFromRight = null;
boolean isLeft = left.hasColumn(c);
boolean isRight = right.hasColumn(c);
if (isLeft && isRight) {
throw new IllegalArgumentException("Column '" + c.getColumnName() + "' is ambiguous in JoinNode");
}
if (isLeft) {// 可能在select/from中
resFromLeft = this.getColumnFromOtherNode(c, left);
if (resFromLeft == null) {// 如果不在select中，添加到select进行join传递
left.addColumnsSelected(c.copy());
resFromLeft = this.getColumnFromOtherNode(c, left);
}
}
if (isRight) {// 可能在select/from中
resFromRight = this.getColumnFromOtherNode(c, right);
if (resFromRight == null) {// 如果不在select中，添加到select进行join传递
right.addColumnsSelected(c.copy());
resFromRight = this.getColumnFromOtherNode(c, right);
}
}
return resFromLeft == null ? resFromRight : resFromLeft;
}
public void buildFunction(IFunction f) {
if (f.getArgs().size() == 0) {
return;
}
List<Object> args = f.getArgs();
for (int i = 0; i < args.size(); i++) {
if (args.get(i) instanceof ISelectable) {
args.set(i, this.buildSelectable((ISelectable) args.get(i)));
if (IFunction.FunctionType.Aggregate.equals(f.getFunctionType()) && (args.get(i) instanceof IColumn)) {
this.columnInAggregate.add((IColumn) args.get(i));
}
}
}
}
}