commit 14c865e8592ff73e1e1ca2070ff660771ba20e78
author drh <drh@noemail.net> Sat Aug 10 15:06:03 2019 +0000
committer drh <drh@noemail.net> Sat Aug 10 15:06:03 2019 +0000
tree c8afde8042f09e740b84f2d580c11980f8443c71
parent b6299681c63e5ea8b61892f4e5dffaac25031723

Fix the sqliteExprImpliesExpr() routine so that it recognizes that
"(NULL IS FALSE) IS FALSE" doe not implie "NULL NOT NULL".
Ticket [9080b6227fabb466]

FossilOrigin-Name: da01ba4fa47c6508b31533ccd769e637af04bd37f51463372fbc6c848d892a4d

src/expr.c

diff --git a/src/expr.c b/src/expr.c
index 376da57..e00b319 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -4938,7 +4938,9 @@
 ){
   assert( p );
   assert( pNN );
-  if( sqlite3ExprCompare(pParse, p, pNN, iTab)==0 ) return 1;
+  if( sqlite3ExprCompare(pParse, p, pNN, iTab)==0 ){
+    return pNN->op!=TK_NULL;
+  }
   switch( p->op ){
     case TK_IN: {
       if( seenNot && ExprHasProperty(p, EP_xIsSelect) ) return 0;