we have to hide current subQueryInfo if we are going to optimize query expression

h2/src/main/org/h2/engine/Session.java

@@ -17,6 +17,7 @@ import org.h2.command.Command;
 import org.h2.command.CommandInterface;
 import org.h2.command.Parser;
 import org.h2.command.Prepared;
+import org.h2.command.dml.Query;
 import org.h2.command.dml.SetTypes;
 import org.h2.constraint.Constraint;
 import org.h2.index.Index;
@@ -115,6 +116,7 @@ public class Session extends SessionWithState {
     private long modificationMetaID = -1;
     private SubQueryInfo subQueryInfo;
     private int parsingView;
+    private int preparingQueryExpression;
     private volatile SmallLRUCache<Object, ViewIndex> viewIndexCache;
     private HashMap<Object, ViewIndex> subQueryIndexCache;
     private boolean joinBatchEnabled;
@@ -187,6 +189,24 @@ public class Session extends SessionWithState {
         return parsingView != 0;
     }
 
+    public void optimizeQueryExpression(Query query) {
+        // we have to hide current subQueryInfo if we are going to optimize query expression
+        SubQueryInfo tmp = subQueryInfo;
+        subQueryInfo = null;
+        preparingQueryExpression++;
+        try {
+            query.prepare();
+        } finally {
+            subQueryInfo = tmp;
+            preparingQueryExpression--;
+        }
+    }
+
+    public boolean isPreparingQueryExpression() {
+        assert preparingQueryExpression >= 0;
+        return preparingQueryExpression != 0;
+    }
+
     @Override
     public ArrayList<String> getClusterServers() {
         return new ArrayList<String>();

h2/src/main/org/h2/expression/ConditionExists.java

@@ -9,6 +9,7 @@ import org.h2.command.dml.Query;
 import org.h2.engine.Session;
 import org.h2.result.LocalResult;
 import org.h2.table.ColumnResolver;
+import org.h2.table.SubQueryInfo;
 import org.h2.table.TableFilter;
 import org.h2.util.StringUtils;
 import org.h2.value.Value;
@@ -36,7 +37,7 @@ public class ConditionExists extends Condition {
 
     @Override
     public Expression optimize(Session session) {
-        query.prepare();
+        session.optimizeQueryExpression(query);
         return this;
     }
 

h2/src/main/org/h2/expression/ConditionInSelect.java

@@ -13,6 +13,7 @@ import org.h2.index.IndexCondition;
 import org.h2.message.DbException;
 import org.h2.result.LocalResult;
 import org.h2.table.ColumnResolver;
+import org.h2.table.SubQueryInfo;
 import org.h2.table.TableFilter;
 import org.h2.util.StringUtils;
 import org.h2.value.Value;
@@ -117,7 +118,7 @@ public class ConditionInSelect extends Condition {
     public Expression optimize(Session session) {
         left = left.optimize(session);
         query.setRandomAccessResult(true);
-        query.prepare();
+        session.optimizeQueryExpression(query);
         if (query.getColumnCount() != 1) {
             throw DbException.get(ErrorCode.SUBQUERY_IS_NOT_SINGLE_COLUMN);
         }

h2/src/main/org/h2/expression/Subquery.java

@@ -6,13 +6,13 @@
 package org.h2.expression;
 
 import java.util.ArrayList;
-
 import org.h2.api.ErrorCode;
 import org.h2.command.dml.Query;
 import org.h2.engine.Session;
 import org.h2.message.DbException;
 import org.h2.result.ResultInterface;
 import org.h2.table.ColumnResolver;
+import org.h2.table.SubQueryInfo;
 import org.h2.table.TableFilter;
 import org.h2.value.Value;
 import org.h2.value.ValueArray;
@@ -70,7 +70,7 @@ public class Subquery extends Expression {
 
     @Override
     public Expression optimize(Session session) {
-        query.prepare();
+        session.optimizeQueryExpression(query);
         return this;
     }
 

h2/src/test/org/h2/test/db/TestTableEngines.java

@@ -73,6 +73,7 @@ public class TestTableEngines extends TestBase {
 
     @Override
     public void test() throws Exception {
+        testQueryExpressionFlag();
         testSubQueryInfo();
         testEarlyFilter();
         testEngineParams();
@@ -347,6 +348,21 @@ public class TestTableEngines extends TestBase {
         deleteDb("tableEngine");
     }
 
+    private void testQueryExpressionFlag() throws SQLException {
+        deleteDb("testQueryExpressionFlag");
+        Connection conn = getConnection("testQueryExpressionFlag");
+        Statement stat = conn.createStatement();
+        stat.execute("create table QRY_EXPR_TEST(id int) ENGINE \"" + 
+                TreeSetIndexTableEngine.class.getName() + "\"");
+        stat.execute("create table QRY_EXPR_TEST_NO(id int) ENGINE \"" + 
+                TreeSetIndexTableEngine.class.getName() + "\"");
+        stat.executeQuery("select 1 + (select 1 from QRY_EXPR_TEST)").next();
+        stat.executeQuery("select 1 from QRY_EXPR_TEST_NO where id in (select id from QRY_EXPR_TEST)");
+        stat.executeQuery("select 1 from QRY_EXPR_TEST_NO n "
+                + "where exists(select 1 from QRY_EXPR_TEST y where y.id = n.id)");
+        deleteDb("testQueryExpressionFlag");
+    }
+
     private void testSubQueryInfo() throws SQLException {
         deleteDb("testSubQueryInfo");
         Connection conn = getConnection("testSubQueryInfo");
@@ -1130,6 +1146,7 @@ public class TestTableEngines extends TestBase {
             @Override
             public double getCost(Session session, int[] masks,
                     TableFilter[] filters, int filter, SortOrder sortOrder) {
+                doTests(session);
                 return getRowCount(session) + Constants.COST_ROW_OFFSET;
             }
         };
@@ -1312,7 +1329,7 @@ public class TestTableEngines extends TestBase {
 
         @Override
         public IndexLookupBatch createLookupBatch(final TableFilter filter) {
-            assert filter.getMasks() != null || "scan".equals(getName());
+            assert0(filter.getMasks() != null || "scan".equals(getName()), "masks");
             final int preferedSize = preferedBatchSize; 
             if (preferedSize == 0) {
                 return null;
@@ -1454,9 +1471,7 @@ public class TestTableEngines extends TestBase {
             }
         }
 
-        @Override
-        public double getCost(Session session, int[] masks,
-                TableFilter[] filters, int filter, SortOrder sortOrder) {
+        protected void doTests(Session session) {
             if (getTable().getName().equals("SUB_QUERY_TEST")) {
                 checkInfo(session.getSubQueryInfo());
             } else if (getTable().getName().equals("EXPR_TEST")) {
@@ -1465,7 +1480,17 @@ public class TestTableEngines extends TestBase {
                 String alias = alias(session.getSubQueryInfo());
                 assert0(alias.equals("ZZ"), "select expression sub-query: " + alias);
                 assert0(session.getSubQueryInfo().getUpper() == null, "upper");
+            } else if (getTable().getName().equals("QRY_EXPR_TEST")) {
+                assert0(session.isPreparingQueryExpression(), "preparing query expression");
+            } else if (getTable().getName().equals("QRY_EXPR_TEST_NO")) {
+                assert0(!session.isPreparingQueryExpression(), "not preparing query expression");
+            }
         }
+
+        @Override
+        public double getCost(Session session, int[] masks,
+                TableFilter[] filters, int filter, SortOrder sortOrder) {
+            doTests(session);
             return getCostRangeIndex(masks, set.size(), filters, filter, sortOrder);
         }