Issue 387: WHERE condition getting pushed into sub-query with LIMIT.

h2/src/docsrc/html/changelog.html

@@ -18,7 +18,7 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>-
+<ul><li>Issue 387: WHERE condition getting pushed into sub-query with LIMIT.
 </li></ul>
 
 <h2>Version 1.3.165 (2012-03-18)</h2>

h2/src/main/org/h2/command/dml/Query.java

@@ -171,6 +171,15 @@ public abstract class Query extends Prepared {
      */
     public abstract void addGlobalCondition(Parameter param, int columnId, int comparisonType);
 
+    /**
+     * Check whether adding condition to the query is allowed. This is not
+     * allowed for views that have an order by and a limit, as it would affect
+     * the returned results.
+     *
+     * @return true if adding global conditions is allowed
+     */
+    public abstract boolean allowGlobalConditions();
+
     /**
      * Check if this expression and all sub-expressions can fulfill a criteria.
      * If any part returns false, the result is false.

h2/src/main/org/h2/command/dml/Select.java

@@ -1258,4 +1258,11 @@ public class Select extends Query {
         return CommandInterface.SELECT;
     }
 
+    public boolean allowGlobalConditions() {
+        if (offsetExpr == null && (limitExpr == null || sort == null)) {
+            return true;
+        }
+        return false;
+    }
+
 }

h2/src/main/org/h2/command/dml/SelectUnion.java

@@ -413,4 +413,8 @@ public class SelectUnion extends Query {
         return CommandInterface.SELECT;
     }
 
+    public boolean allowGlobalConditions() {
+        return left.allowGlobalConditions() && right.allowGlobalConditions();
+    }
+
 }

h2/src/main/org/h2/index/ViewIndex.java

@@ -260,6 +260,9 @@ public class ViewIndex extends BaseIndex {
         if (masks == null) {
             return q;
         }
+        if (!q.allowGlobalConditions()) {
+            return q;
+        }
         int firstIndexParam = originalParameters == null ? 0 : originalParameters.size();
         firstIndexParam += view.getParameterOffset();
         IntArray paramIndex = new IntArray();

h2/src/test/org/h2/test/test-1.3.txt

 --- special grammar and test cases ---------------------------------------------------------------------------------------------
+create table test(id int, name varchar);
+> ok
+
+insert into test values(5, 'b'), (5, 'b'), (20, 'a');
+> update count: 3
+
+select * from (select * from test order by name limit 1) where id < 10;
+> ID NAME
+> -- ----
+> rows (ordered): 0
+
+drop table test;
+> ok
+
 create table test (id int not null, pid int);
 > ok