Bug#20327: Marking of a wrong field leads to a wrong result on select with view,

prepared statement and subquery.

When a field of a view from an outer select is resolved the find_field_in_view
function creates an Item_direct_view_ref object that references the 
corresponding view underlying field. After that the view_ref is marked
as a dependent one. While resolving view underlying field it also get
marked as a dependent one due to current_select still points to the subselect.
Marking the view underlying field is wrong and lead to attaching conditions
to a wrong table and thus to the wrong result of the whole statement.

Now mark_select_range_as_dependent() function isn't called for fields from a 
view underlying table.

mysql-test/r/ps.result

@@ -1379,4 +1379,22 @@ i
 1
 DEALLOCATE PREPARE stmt;
 DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+CREATE VIEW v1 AS SELECT * FROM t1;
+INSERT INTO t1 VALUES (1), (2);
+SELECT t1.i FROM t1 JOIN v1 ON t1.i = v1.i
+WHERE EXISTS (SELECT * FROM t1 WHERE v1.i = 1);
+i
+1
+PREPARE stmt FROM "SELECT t1.i FROM t1 JOIN v1 ON t1.i = v1.i
+WHERE EXISTS (SELECT * FROM t1 WHERE v1.i = 1)";
+EXECUTE stmt;
+i
+1
+EXECUTE stmt;
+i
+1
+DEALLOCATE PREPARE stmt;
+DROP VIEW v1;
+DROP TABLE t1;
 End of 5.0 tests.

mysql-test/t/ps.test

@@ -1437,4 +1437,26 @@ DEALLOCATE PREPARE stmt;
 DROP TABLE t1, t2;
 
 
+#
+# BUG#20327: Marking of a wrong field leads to a wrong result on select with
+#            view, prepared statement and subquery.
+#
+CREATE TABLE t1 (i INT);
+CREATE VIEW v1 AS SELECT * FROM t1;
+
+INSERT INTO t1 VALUES (1), (2);
+
+let $query = SELECT t1.i FROM t1 JOIN v1 ON t1.i = v1.i
+             WHERE EXISTS (SELECT * FROM t1 WHERE v1.i = 1);
+eval $query;
+eval PREPARE stmt FROM "$query";
+# Statement execution should return '1'.
+EXECUTE stmt;
+# Check re-execution.
+EXECUTE stmt;
+
+DEALLOCATE PREPARE stmt;
+DROP VIEW v1;
+DROP TABLE t1;
+
 --echo End of 5.0 tests.

sql/sql_base.cc

@@ -3303,6 +3303,12 @@ find_field_in_tables(THD *thd, Item_ident *item,
     {
       if (found == WRONG_GRANT)
 	return (Field*) 0;
+
+      /*
+        Only views fields should be marked as dependent, not an underlying
+        fields.
+      */
+      if (!table_ref->belong_to_view)
       {
         SELECT_LEX *current_sel= thd->lex->current_select;
         SELECT_LEX *last_select= table_ref->select_lex;