Index: src/expr.c
==================================================================
--- src/expr.c
+++ src/expr.c
@@ -5166,14 +5166,15 @@
         return WRC_Abort;
       }
       return WRC_Prune;
 
     case TK_AND:
-      if( sqlite3ExprImpliesNonNullRow(pExpr->pLeft, pWalker->u.iCur)
-       && sqlite3ExprImpliesNonNullRow(pExpr->pRight, pWalker->u.iCur)
-      ){
-        pWalker->eCode = 1;
+      assert( pWalker->eCode==0 );
+      sqlite3WalkExpr(pWalker, pExpr->pLeft);
+      if( pWalker->eCode ){
+        pWalker->eCode = 0;
+        sqlite3WalkExpr(pWalker, pExpr->pRight);
       }
       return WRC_Prune;
 
     case TK_BETWEEN:
       sqlite3WalkExpr(pWalker, pExpr->pLeft);
@@ -5228,19 +5229,12 @@
 ** ordinary join.
 */
 int sqlite3ExprImpliesNonNullRow(Expr *p, int iTab){
   Walker w;
   p = sqlite3ExprSkipCollateAndLikely(p);
-  while( p ){
-    if( p->op==TK_NOTNULL ){
-      p = p->pLeft;
-    }else if( p->op==TK_AND ){
-      if( sqlite3ExprImpliesNonNullRow(p->pLeft, iTab) ) return 1;
-      p = p->pRight;
-    }else{
-      break;
-    }
+  if( p && p->op==TK_NOTNULL ){
+    p = p->pLeft;
   }
   w.xExprCallback = impliesNotNullRow;
   w.xSelectCallback = 0;
   w.xSelectCallback2 = 0;
   w.eCode = 0;

Index: test/join.test
==================================================================
--- test/join.test
+++ test/join.test
@@ -902,8 +902,38 @@
 } {1 {}}
 
 do_execsql_test join-18.4 {
   SELECT NOT(v0.a IS FALSE) FROM v0
 } {1}
+
+#-------------------------------------------------------------------------
+reset_db
+do_execsql_test join-19.0 {
+  CREATE TABLE t1(a);
+  CREATE TABLE t2(b);
+  INSERT INTO t1(a) VALUES(0);
+  CREATE VIEW v0(c) AS SELECT t2.b FROM t1 LEFT JOIN t2;
+}
+
+do_execsql_test join-19.1 {
+  SELECT * FROM v0 WHERE v0.c NOTNULL NOTNULL; 
+} {{}}
+
+do_execsql_test join-19.2 {
+  SELECT * FROM t1 LEFT JOIN t2
+} {0 {}}
+
+do_execsql_test join-19.3 {
+  SELECT * FROM t1 LEFT JOIN t2 WHERE (b IS NOT NULL) IS NOT NULL; 
+} {0 {}}
+
+do_execsql_test join-19.4 {
+  SELECT (b IS NOT NULL) IS NOT NULL FROM t1 LEFT JOIN t2
+} {1}
+
+do_execsql_test join-19.5 {
+  SELECT * FROM t1 LEFT JOIN t2 WHERE 
+    (b IS NOT NULL AND b IS NOT NULL) IS NOT NULL; 
+} {0 {}}
 
 finish_test