Fixing issue when a hash was tried to be generated on the null value from XML extract causing to fail. Please see #1098

lwasylow · lwasylow · commit 3c3d32055457 · 2022-01-26T10:46:41.000Z
Resolve a situation where a more than two levels of nesting were causing ambiguity on the column name for hash.
E.g.
&lt;OBJ1&gt;&lt;FIRST&gt;&lt;VAL&gt;&lt;TEST&gt;
&lt;OBJ1&gt;&lt;SECOND&gt;&lt;VAL&gt;&lt;TEST&gt;
Was taking into hash consideration only parent.
diff --git a/source/core/ut_utils.pkb b/source/core/ut_utils.pkb
@@ -882,12 +882,14 @@ create or replace package body ut_utils is
 
   function get_hash(a_data raw, a_hash_type binary_integer := dbms_crypto.hash_sh1) return t_hash is
   begin
-    return dbms_crypto.hash(a_data, a_hash_type);
+    --We cannot run hash on null
+    return case when a_data is null then null else dbms_crypto.hash(a_data, a_hash_type) end;
   end;
 
   function get_hash(a_data clob, a_hash_type binary_integer := dbms_crypto.hash_sh1) return t_hash is
   begin
-    return dbms_crypto.hash(a_data, a_hash_type);
+    --We cannot run hash on null
+    return case when a_data is null then null else dbms_crypto.hash(a_data, a_hash_type) end;
   end;
 
   function qualified_sql_name(a_name varchar2) return varchar2 is
diff --git a/source/expectations/data_values/ut_cursor_column.tpb b/source/expectations/data_values/ut_cursor_column.tpb
@@ -28,12 +28,13 @@ create or replace type body ut_cursor_column as
                                  a_access_path||'/'||self.xml_valid_name 
                                end; --Access path used for XMLTABLE query   
       self.filter_path      := '/'||self.access_path; --Filter path will differ from access path in anydata type
+      --Transformed name needs to be build on full access path to avoid ambiguity when there is 3 or more levels of nesting.
       self.transformed_name := case when length(self.xml_valid_name) > 30 then
-                                 '"'||ut_compound_data_helper.get_fixed_size_hash(self.parent_name||self.xml_valid_name)||'"'
+                                 '"'||ut_compound_data_helper.get_fixed_size_hash(self.access_path)||'"'
                                when self.parent_name is null then 
                                  '"'||self.xml_valid_name||'"'
                                else 
-                                 '"'||ut_compound_data_helper.get_fixed_size_hash(self.parent_name||self.xml_valid_name)||'"'
+                                 '"'||ut_compound_data_helper.get_fixed_size_hash(self.access_path)||'"'
                                end; --when is nestd we need to hash name to make sure we dont exceed 30 char
       self.column_type      := a_col_type; --column type e.g. user_defined , varchar2
       self.column_schema    := a_col_schema_name; -- schema name
