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1
5 package org.h2.expression;
6
7 import java.sql.SQLException  ;
8
9 import org.h2.engine.Constants;
10 import org.h2.engine.Database;
11 import org.h2.engine.Session;
12 import org.h2.index.IndexCondition;
13 import org.h2.table.ColumnResolver;
14 import org.h2.table.TableFilter;
15 import org.h2.util.ObjectArray;
16 import org.h2.value.CompareMode;
17 import org.h2.value.Value;
18 import org.h2.value.ValueBoolean;
19 import org.h2.value.ValueNull;
20
21
24
25 public class ConditionIn extends Condition {
26 private Database database;
27 private Expression left;
28 private ObjectArray values;
29 private Value min, max;
30 private int queryLevel;
31
32 public ConditionIn(Database database, Expression left, ObjectArray values) {
33 this.database = database;
34 this.left = left;
35 this.values = values;
36 }
37
38 public Value getValue(Session session) throws SQLException {
39 Value l = left.getValue(session);
40 if(l == ValueNull.INSTANCE) {
41 return l;
42 }
43 boolean result = false;
44 boolean hasNull = false;
45 for(int i=0; i<values.size(); i++) {
46 Expression e = (Expression) values.get(i);
47 Value r = e.getValue(session);
48 if(r == ValueNull.INSTANCE) {
49 hasNull = true;
50 } else {
51 result = Comparison.compareNotNull(database, l, r, Comparison.EQUAL);
52 if(result) {
53 break;
54 }
55 }
56 }
57 if(!result && hasNull) {
58 return ValueNull.INSTANCE;
59 }
60 return ValueBoolean.get(result);
61 }
62
63 public void mapColumns(ColumnResolver resolver, int queryLevel) throws SQLException {
64 left.mapColumns(resolver, queryLevel);
65 for(int i=0; i<values.size(); i++) {
66 Expression e = (Expression) values.get(i);
67 e.mapColumns(resolver, queryLevel);
68 }
69 this.queryLevel = Math.max(queryLevel, this.queryLevel);
70 }
71
72 public Expression optimize(Session session) throws SQLException {
73 left = left.optimize(session);
74 boolean constant = left.isConstant();
75 if(constant && left == ValueExpression.NULL) {
76 return left;
77 }
78 boolean allValuesConstant = true;
79 for(int i=0; i<values.size(); i++) {
80 Expression e = (Expression) values.get(i);
81 e = e.optimize(session);
82 if(allValuesConstant && !e.isConstant()) {
83 allValuesConstant = false;
84 }
85 values.set(i, e);
86 }
87 if(constant && allValuesConstant) {
88 return ValueExpression.get(getValue(session));
89 }
90 if(values.size()==1) {
92 Expression right = (Expression) values.get(0);
93 Expression expr = new Comparison(session, Comparison.EQUAL, left, right);
94 expr = expr.optimize(session);
95 return expr;
96 }
97 if(Constants.OPTIMIZE_IN) {
98 ExpressionVisitor independent = ExpressionVisitor.get(ExpressionVisitor.INDEPENDENT);
99 independent.queryLevel = queryLevel;
100 if(areAllValues(independent)) {
101 if(left instanceof ExpressionColumn) {
102 CompareMode mode = session.getDatabase().getCompareMode();
103 for(int i=0; i<values.size(); i++) {
104 Expression e = (Expression) values.get(i);
105 Value v = e.getValue(session);
106 values.set(i, ValueExpression.get(v));
107 if(min == null || min.compareTo(v, mode) > 0) {
108 min = v;
109 }
110 if(max == null || max.compareTo(v, mode) < 0) {
111 max = v;
112 }
113 }
114 }
115 }
116 }
117 return this;
118 }
119
120 public void createIndexConditions(TableFilter filter) {
121 if(!Constants.OPTIMIZE_IN) {
122 return;
123 }
124 if(min == null && max == null) {
125 return;
126 }
127 if(!(left instanceof ExpressionColumn)) {
128 return;
129 }
130 ExpressionColumn l = (ExpressionColumn)left;
131 if(filter != l.getTableFilter()) {
132 return;
133 }
134 filter.addIndexCondition(new IndexCondition(Comparison.BIGGER_EQUAL, l, ValueExpression.get(min)));
135 filter.addIndexCondition(new IndexCondition(Comparison.SMALLER_EQUAL, l, ValueExpression.get(max)));
136 }
137
138 public void setEvaluatable(TableFilter tableFilter, boolean b) {
139 left.setEvaluatable(tableFilter, b);
140 for(int i=0; i<values.size(); i++) {
141 Expression e = (Expression) values.get(i);
142 e.setEvaluatable(tableFilter, b);
143 }
144 }
145
146 public String getSQL() {
147 StringBuffer buff = new StringBuffer ("(");
148 buff.append(left.getSQL());
149 buff.append(" IN(");
150 for(int i=0; i<values.size(); i++) {
151 if(i>0) {
152 buff.append(", ");
153 }
154 Expression e = (Expression) values.get(i);
155 buff.append(e.getSQL());
156 }
157 buff.append("))");
158 return buff.toString();
159 }
160
161 public void updateAggregate(Session session) throws SQLException {
162 left.updateAggregate(session);
163 for(int i=0; i<values.size(); i++) {
164 Expression e = (Expression) values.get(i);
165 e.updateAggregate(session);
166 }
167 }
168
169 public boolean isEverything(ExpressionVisitor visitor) {
170 if(!left.isEverything(visitor)) {
171 return false;
172 }
173 return areAllValues(visitor);
174 }
175
176 private boolean areAllValues(ExpressionVisitor visitor) {
177 for(int i=0; i<values.size(); i++) {
178 Expression e = (Expression) values.get(i);
179 if(!e.isEverything(visitor)) {
180 return false;
181 }
182 }
183 return true;
184 }
185
186 public int getCost() {
187 int cost = left.getCost();
188 for(int i=0; i<values.size(); i++) {
189 Expression e = (Expression) values.get(i);
190 cost += e.getCost();
191 }
192 return cost;
193 }
194
195 }
196 |
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