Added support for sys.fn_varbintohexsubstring function

contrib/babelfishpg_tsql/sql/sys_functions.sql

@@ -4135,14 +4135,40 @@ BEGIN
 END; 
 $$ LANGUAGE plpgsql STABLE;
 
-CREATE OR REPLACE FUNCTION sys.fn_varbintohexsubstring(set_prefix INT, expression sys.varbinary(128), start_offset INT, length_to_return INT) 
-RETURNS sys.nvarchar(128) 
-AS $$ 
+CREATE OR REPLACE FUNCTION sys.fn_varbintohexsubstring(set_prefix INT, expression sys.varbinary(128), start_offset INT, substr_length INT)
+RETURNS sys.nvarchar(128) AS 
+$$ 
 DECLARE 
+    pstrout sys.nvarchar(128);
+    hex_str text;
 BEGIN 
-    RETURN NULL; 
-END; 
-$$ LANGUAGE plpgsql STABLE;
+    IF expression IS NULL THEN 
+        RETURN NULL;
+    END IF;
+
+    IF substr_length IS NULL OR substr_length <= 0 OR substr_length > LEN(expression) THEN 
+        substr_length := LEN(expression);
+    END IF;
+
+    IF start_offset < 1 OR start_offset > LEN(expression) THEN 
+        RETURN NULL;
+    END IF;
+
+    IF (LEN(expression) - start_offset + 1) < substr_length THEN 
+        substr_length := LEN(expression) - start_offset + 1;
+    END IF;
+
+    hex_str := LOWER(ENCODE(SUBSTRING(expression, start_offset, substr_length)::bytea, 'hex'));
+
+    pstrout := CASE 
+                WHEN set_prefix IS NULL THEN N''
+                WHEN set_prefix = 0 THEN N'' 
+                ELSE N'0x' 
+               END || hex_str;
+    RETURN pstrout;
+END;
+$$ 
+LANGUAGE plpgsql STABLE;
 
 CREATE OR REPLACE FUNCTION objectproperty(
     id INT,

contrib/babelfishpg_tsql/sql/upgrades/babelfishpg_tsql--5.1.0--5.2.0.sql

@@ -450,11 +450,6 @@ BEGIN
 END;
 $$;
 
--- After upgrade, always run analyze for all babelfish catalogs.
-CALL sys.analyze_babelfish_catalogs();
--- Reset search_path to not affect any subsequent scripts
-SELECT set_config('search_path', trim(leading 'sys, ' from current_setting('search_path')), false);
-
 CREATE OR REPLACE FUNCTION sys.loginproperty(login_name sys.sysname, property_name sys.nvarchar(128)) 
 RETURNS sys.nvarchar(128) 
 AS $$ 
@@ -464,14 +459,40 @@ BEGIN
 END; 
 $$ LANGUAGE plpgsql STABLE;
 
-CREATE OR REPLACE FUNCTION sys.fn_varbintohexsubstring(set_prefix INT, expression sys.varbinary(128), start_offset INT, length_to_return INT) 
-RETURNS sys.nvarchar(128) 
-AS $$ 
+CREATE OR REPLACE FUNCTION sys.fn_varbintohexsubstring(set_prefix INT, expression sys.varbinary(128), start_offset INT, substr_length INT)
+RETURNS sys.nvarchar(128) AS 
+$$ 
 DECLARE 
+    pstrout sys.nvarchar(128);
+    hex_str text;
 BEGIN 
-    RETURN NULL; 
-END; 
-$$ LANGUAGE plpgsql STABLE;
+    IF expression IS NULL THEN 
+        RETURN NULL;
+    END IF;
+
+    IF substr_length IS NULL OR substr_length <= 0 OR substr_length > LEN(expression) THEN 
+        substr_length := LEN(expression);
+    END IF;
+
+    IF start_offset < 1 OR start_offset > LEN(expression) THEN 
+        RETURN NULL;
+    END IF;
+
+    IF (LEN(expression) - start_offset + 1) < substr_length THEN 
+        substr_length := LEN(expression) - start_offset + 1;
+    END IF;
+
+    hex_str := LOWER(ENCODE(SUBSTRING(expression, start_offset, substr_length)::bytea, 'hex'));
+
+    pstrout := CASE 
+                WHEN set_prefix IS NULL THEN N''
+                WHEN set_prefix = 0 THEN N'' 
+                ELSE N'0x' 
+               END || hex_str;
+    RETURN pstrout;
+END;
+$$ 
+LANGUAGE plpgsql STABLE;
 
 CREATE OR REPLACE VIEW sys.server_permissions 
 AS
@@ -523,3 +544,7 @@ SELECT
 WHERE FALSE;
 GRANT SELECT ON sys.sql_logins TO PUBLIC;
 
+-- After upgrade, always run analyze for all babelfish catalogs.
+CALL sys.analyze_babelfish_catalogs();
+-- Reset search_path to not affect any subsequent scripts
+SELECT set_config('search_path', trim(leading 'sys, ' from current_setting('search_path')), false);

test/JDBC/expected/sys-fn-varbintohexsubstring-vu-verify.out

@@ -1,23 +1,208 @@
+-- dependent objects
 SELECT * FROM fn_varbintohexsubstring_vu_prepare_view
 GO
 ~~START~~
 nvarchar
-<NULL>
+0x30783132
 ~~END~~
 
 
 EXEC fn_varbintohexsubstring_vu_prepare_proc
 GO
 ~~START~~
 nvarchar
-<NULL>
+0x30783132
 ~~END~~
 
 
 SELECT * FROM fn_varbintohexsubstring_vu_prepare_func()
 GO
 ~~START~~
 nvarchar
+0x30783132
+~~END~~
+
+
+-- NULL expression results in NULL output
+SELECT sys.fn_varbintohexsubstring(0,0x,1,3);
+GO
+~~START~~
+nvarchar
+<NULL>
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(0,CAST(NULL AS VARBINARY),1,4);
+GO
+~~START~~
+nvarchar
+<NULL>
+~~END~~
+
+
+-- if substr_length is NULL, negative, zero or greater than length of expression, set substr_length as length of expression
+SELECT sys.fn_varbintohexsubstring(1,0x123486534659789876435656,1,NULL);
+GO
+~~START~~
+nvarchar
+0x123486534659789876435656
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(1, 0x123486534659789876435656, 1, -5);
+GO
+~~START~~
+nvarchar
+0x123486534659789876435656
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(1,0x123486534659789876435656,1,0);
+GO
+~~START~~
+nvarchar
+0x123486534659789876435656
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(1,0x123486534659789876435656,1,100);
+GO
+~~START~~
+nvarchar
+0x123486534659789876435656
+~~END~~
+
+
+-- if substr_length is out of bounds of the expression, then len is set to the length of expression - start_offset
+SELECT sys.fn_varbintohexsubstring(1, 0x123486534659789876435656, 3, 20);
+GO
+~~START~~
+nvarchar
+0x86534659789876435656
+~~END~~
+
+
+-- if set_prefix is NULL or 0, no prefix is added
+SELECT sys.fn_varbintohexsubstring(NULL,0x123486534659789876435656,1,4);
+GO
+~~START~~
+nvarchar
+12348653
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(0,0x123486534659789876435656,1,4);
+GO
+~~START~~
+nvarchar
+12348653
+~~END~~
+
+
+-- if set_prefix is 1 or any other integer except 0, prefix is added
+SELECT sys.fn_varbintohexsubstring(1,0x123486534659789876435656,1,4);
+GO
+~~START~~
+nvarchar
+0x12348653
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(52,0x123486534659789876435656,1,4);
+GO
+~~START~~
+nvarchar
+0x12348653
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(-81,0x123486534659789876435656,1,4);
+GO
+~~START~~
+nvarchar
+0x12348653
+~~END~~
+
+
+-- if start_offset is NULL or 0 or negative, return NULL
+SELECT sys.fn_varbintohexsubstring(1,0x87243478679,NULL,4);
+GO
+~~START~~
+nvarchar
 <NULL>
 ~~END~~
 
+
+SELECT sys.fn_varbintohexsubstring(1,0x87243478679,CAST(NULL AS INT),4);
+GO
+~~START~~
+nvarchar
+<NULL>
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(1,0x87243478679,0,4);
+GO
+~~START~~
+nvarchar
+<NULL>
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(1, 0x123456, -1, 2);
+GO
+~~START~~
+nvarchar
+<NULL>
+~~END~~
+
+
+-- if start_offset is out of bound, return NULL
+SELECT sys.fn_varbintohexsubstring(1, 0x123456, 100, 2);
+GO
+~~START~~
+nvarchar
+<NULL>
+~~END~~
+
+
+-- NULL edge cases
+SELECT sys.fn_varbintohexsubstring(NULL,NULL,NULL,NULL);
+GO
+~~START~~
+nvarchar
+<NULL>
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(NULL,0x8675235657899765,NULL,NULL);
+GO
+~~START~~
+nvarchar
+<NULL>
+~~END~~
+
+
+SELECT sys.fn_varbintohexsubstring(NULL,0x8675235657899765,2,NULL);
+GO
+~~START~~
+nvarchar
+75235657899765
+~~END~~
+
+
+--negative test as varbinary only consists of 0-9 and A-F
+SELECT sys.fn_varbintohexsubstring(1,0x1452J5S4, 2, 4);  
+GO
+~~ERROR (Code: 33557097)~~
+
+~~ERROR (Message: syntax error near '.' at line 2 and character position 10)~~
+
+
+-- negative test gives error as the expression datatype is not varbinary
+SELECT sys.fn_varbintohexsubstring(1,'1A2B3C4D', 2, 4);  
+GO
+~~ERROR (Code: 33557097)~~
+
+~~ERROR (Message: cannot coerce string literal to varbinary datatype)~~
+