Fix issue with truncation of result of arithmetic computations to correct scale when result is of numeric datatype

contrib/babelfishpg_tds/src/include/tds_response.h

@@ -98,6 +98,6 @@ extern void TDSStatementExceptionCallback(PLtsql_execstate *estate, PLtsql_stmt
 										  bool terminate_batch);
 extern void SendColumnMetadata(TupleDesc typeinfo, List *targetlist, int16 *formats);
 extern bool GetTdsEstateErrorData(int *number, int *severity, int *state);
-extern int32 resolve_numeric_typmod_from_exp(Plan *plan, Node *expr);
+extern int32 resolve_numeric_typmod_from_exp(Plan *plan, Node *expr, bool *found);
 
 #endif							/* TDS_H */

contrib/babelfishpg_tsql/src/hooks.c

@@ -192,6 +192,8 @@ static void pltsql_ExecutorRun(QueryDesc *queryDesc, ScanDirection direction, ui
 static void pltsql_ExecutorFinish(QueryDesc *queryDesc);
 static void pltsql_ExecutorEnd(QueryDesc *queryDesc);
 static bool pltsql_bbfViewHasInsteadofTrigger(Relation view, CmdType event);
+static Datum adjust_numeric_result(Plan *plan, Node *expr, Datum result, bool result_isnull, Oid result_type, int32 result_typmod);
+static void pltsql_ExecUpdateResultTypeTL(PlanState *planstate, TupleDesc desc);
 
 static bool plsql_TriggerRecursiveCheck(ResultRelInfo *resultRelInfo);
 static bool bbf_check_rowcount_hook(int es_processed);
@@ -232,6 +234,7 @@ static Oid set_param_collation(Param *param);
 static Oid default_collation_for_builtin_type(Type typ, bool handle_text);
 static char* pltsql_get_object_identity_event_trigger(ObjectAddress *addr);
 static const char *remove_db_name_in_schema(const char *schema_name, const char *object_type);
+static int32 pltsql_exprTypmod(Plan *plan, Node *expr);
 
 /***************************************************
  * 			Temp Table Related Declarations + Hooks
@@ -278,10 +281,13 @@ static pltsql_is_local_only_inval_msg_hook_type prev_pltsql_is_local_only_inval_
 static pltsql_get_tsql_enr_from_oid_hook_type prev_pltsql_get_tsql_enr_from_oid_hook = NULL;
 static inherit_view_constraints_from_table_hook_type prev_inherit_view_constraints_from_table = NULL;
 static bbfViewHasInsteadofTrigger_hook_type prev_bbfViewHasInsteadofTrigger_hook = NULL;
+static adjust_numeric_result_hook_type prev_adjust_numeric_result_hook = NULL;
+static ExecUpdateResultTypeTL_hook_type prev_ExecUpdateResultTypeTL_hook = NULL;
 static detect_numeric_overflow_hook_type prev_detect_numeric_overflow_hook = NULL;
 static match_pltsql_func_call_hook_type prev_match_pltsql_func_call_hook = NULL;
 static insert_pltsql_function_defaults_hook_type prev_insert_pltsql_function_defaults_hook = NULL;
 static replace_pltsql_function_defaults_hook_type prev_replace_pltsql_function_defaults_hook = NULL;
+static exprTypmod_hook_type prev_exprTypmod_hook = NULL;
 static print_pltsql_function_arguments_hook_type prev_print_pltsql_function_arguments_hook = NULL;
 static planner_hook_type prev_planner_hook = NULL;
 static transform_check_constraint_expr_hook_type prev_transform_check_constraint_expr_hook = NULL;
@@ -421,6 +427,12 @@ InstallExtendedHooks(void)
 	prev_bbfViewHasInsteadofTrigger_hook = bbfViewHasInsteadofTrigger_hook;
 	bbfViewHasInsteadofTrigger_hook = pltsql_bbfViewHasInsteadofTrigger;
 
+	prev_adjust_numeric_result_hook = adjust_numeric_result_hook;
+	adjust_numeric_result_hook = adjust_numeric_result;
+
+	prev_ExecUpdateResultTypeTL_hook = ExecUpdateResultTypeTL_hook;
+	ExecUpdateResultTypeTL_hook = pltsql_ExecUpdateResultTypeTL;
+
 	prev_detect_numeric_overflow_hook = detect_numeric_overflow_hook;
 	detect_numeric_overflow_hook = pltsql_detect_numeric_overflow;
 
@@ -433,6 +445,9 @@ InstallExtendedHooks(void)
 	prev_replace_pltsql_function_defaults_hook = replace_pltsql_function_defaults_hook;
 	replace_pltsql_function_defaults_hook = replace_pltsql_function_defaults;
 
+	prev_exprTypmod_hook = exprTypmod_hook;
+	exprTypmod_hook = pltsql_exprTypmod;
+
 	prev_print_pltsql_function_arguments_hook = print_pltsql_function_arguments_hook;
 	print_pltsql_function_arguments_hook = print_pltsql_function_arguments;
 
@@ -578,10 +593,13 @@ UninstallExtendedHooks(void)
 	GetNewTempOidWithIndex_hook = prev_GetNewTempOidWithIndex_hook;
 	inherit_view_constraints_from_table_hook = prev_inherit_view_constraints_from_table;
 	bbfViewHasInsteadofTrigger_hook = prev_bbfViewHasInsteadofTrigger_hook;
+	adjust_numeric_result_hook = prev_adjust_numeric_result_hook;
+	ExecUpdateResultTypeTL_hook = prev_ExecUpdateResultTypeTL_hook;
 	detect_numeric_overflow_hook = prev_detect_numeric_overflow_hook;
 	match_pltsql_func_call_hook = prev_match_pltsql_func_call_hook;
 	insert_pltsql_function_defaults_hook = prev_insert_pltsql_function_defaults_hook;
 	replace_pltsql_function_defaults_hook = prev_replace_pltsql_function_defaults_hook;
+	exprTypmod_hook = prev_exprTypmod_hook;
 	print_pltsql_function_arguments_hook = prev_print_pltsql_function_arguments_hook;
 	planner_hook = prev_planner_hook;
 	transform_check_constraint_expr_hook = prev_transform_check_constraint_expr_hook;
@@ -1199,6 +1217,66 @@ pltsql_bbfViewHasInsteadofTrigger(Relation view, CmdType event)
 	return false;
 }
 
+/*
+ * get_func_id_from_exp
+ *  For expressions T_FuncExpr, T_OpExpr, T_Aggref returns its function Oid
+ */
+static Oid
+get_func_id_from_exp(Node *expr)
+{
+	if (expr == NULL)
+		return InvalidOid;
+
+	switch(nodeTag(expr))
+	{
+		case T_FuncExpr:
+			return ((FuncExpr *) expr)->funcid;
+		case T_OpExpr:
+			return ((OpExpr *) expr)->opfuncid;
+		case T_Aggref:
+			return ((Aggref *) expr)->aggfnoid;
+		default:
+			return InvalidOid;
+	}
+}
+
+/*
+ * adjust_numeric_result
+ *  truncates/rounds the result value to the correct scale based on result_typmod.
+ *  for result_typmod = -1, computes the result_typmod using pltsql_exprTypmod function.
+ */
+static Datum
+adjust_numeric_result(Plan *plan, Node *expr, Datum result, bool result_isnull, Oid result_type, int32 result_typmod)
+{
+	int32       scale;
+	Oid         func_id;
+
+	if (sql_dialect != SQL_DIALECT_TSQL || result_isnull)
+		return result;
+
+	if (!OidIsValid(result_type))
+		result_type = exprType(expr);
+
+	if (result && OidIsValid(result_type) && getBaseType(result_type) == NUMERICOID)
+	{
+		if (expr != NULL && result_typmod == -1)
+			result_typmod = pltsql_exprTypmod(plan, expr);
+
+		if (result_typmod != -1)
+		{
+			scale = (result_typmod - VARHDRSZ) & 0xffff; 
+			func_id = get_func_id_from_exp(expr);
+
+			if (func_id == F_NUMERIC_DIV || func_id == F_AVG_NUMERIC)
+				return DirectFunctionCall2(numeric_trunc, result, Int32GetDatum(scale));
+			else
+				return DirectFunctionCall2(numeric_round, result, Int32GetDatum(scale));
+		}
+	}
+
+	return result;
+}
+
 /*
  * Wrapper function that calls the initilization function.
  * Calls the pre function call hook on the procname 
@@ -6028,6 +6106,92 @@ remove_db_name_in_schema(const char *object_name, const char *object_type)
 	return (const char *)pstrdup(object_name + prefix_len);
 }
 
+/*
+ * pltsql_exprTypmod -
+ *  returns the type-specific modifier of the expression's result type,
+ *  if it can be determined, else we return -1.
+ */
+static int32
+pltsql_exprTypmod(Plan *plan, Node *expr)
+{
+	int32       result_typmod = -1;
+	uint8_t     scale;
+	uint8_t     precision;
+	Oid         expr_type;
+
+	if (sql_dialect != SQL_DIALECT_TSQL || expr == NULL)
+		return -1;
+
+	expr_type = exprType(expr);
+
+	if (!OidIsValid(expr_type))
+		return -1;
+
+	if (getBaseType(expr_type) == NUMERICOID)
+	{
+		/*
+		 * use get_numeric_typmod_from_exp function to get the typmod
+ 		 * from the expression node, when the expression type is numeric.
+		 */ 
+		if (*pltsql_protocol_plugin_ptr && (*pltsql_protocol_plugin_ptr)->get_numeric_typmod_from_exp)
+			result_typmod = (*pltsql_protocol_plugin_ptr)->get_numeric_typmod_from_exp(plan, expr, NULL);
+		if (result_typmod != -1)
+		{
+			/* 
+			 * If we are unable to get correct precision and scale for overflow cases
+			 * then return -1
+			 */
+			scale = (result_typmod - VARHDRSZ) & 0xffff;
+			precision = ((result_typmod - VARHDRSZ) >> 16) & 0xffff;
+			if (precision > TDS_NUMERIC_MAX_PRECISION)
+			{
+				if (!(precision - scale > 32 && scale > 6) && !(precision - scale <= TDS_NUMERIC_MAX_PRECISION))
+					return -1;
+			}
+		}
+	}
+	return result_typmod;
+}
+
+/*
+ * pltsql_ExecUpdateResultTypeTL
+ *
+ * Update typmod of all the entries of a previously initialized tuple descriptor, 
+ * using pltsql_exprTypmod when attribute type is NUMERIC, DECIMAL and any UDT on NUMERIC, DECIMAL.
+ */
+void
+pltsql_ExecUpdateResultTypeTL(PlanState *planstate, TupleDesc desc)
+{
+	ListCell   *l;
+	int         cur_resno = 1;
+	List       *targetList;
+
+	/*
+	 * sanity checks
+	 */
+	if (sql_dialect != SQL_DIALECT_TSQL ||
+		!PointerIsValid(desc) ||
+		!PointerIsValid(planstate) ||
+		!PointerIsValid(planstate->plan) ||
+		!PointerIsValid(planstate->plan->targetlist))
+		return;
+
+	targetList = planstate->plan->targetlist;
+
+	foreach(l, targetList)
+	{
+		TargetEntry *tle = lfirst(l);
+		Form_pg_attribute attr = TupleDescAttr(desc, cur_resno - 1);
+
+		if (getBaseType(attr->atttypid) == NUMERICOID)
+		{
+			attr->atttypmod = pltsql_exprTypmod(planstate->plan, (Node *) tle->expr);
+		}
+
+		cur_resno++;
+	}
+}
+
 /* Check if current connection is a tds connection */
 static bool
 is_bbf_tds_connection(void)

contrib/babelfishpg_tsql/src/pltsql.h

@@ -1800,7 +1800,7 @@ typedef struct PLtsql_protocol_plugin
 	bool		(*get_reset_tds_connection_flag) ();
 	void 		(*get_tvp_typename_typeschemaname) (char *proc_name, char *target_arg_name, 
 													char **tvp_type_name, char **tvp_type_schema_name);
-	int32		(*get_numeric_typmod_from_exp) (Plan *plan, Node *expr);
+	int32		(*get_numeric_typmod_from_exp) (Plan *plan, Node *expr, bool *found);
 	/* Session level GUCs */
 	bool		quoted_identifier;
 	bool		arithabort;

contrib/babelfishpg_tsql/src/pltsql_coerce.c

@@ -2088,7 +2088,7 @@ tsql_select_common_typmod_hook(ParseState *pstate, List *exprs, Oid common_type)
 				type = getBaseTypeAndTypmod(type, &typmod);
 
 			if (typmod == -1 && (*pltsql_protocol_plugin_ptr))
-				typmod = (*pltsql_protocol_plugin_ptr)->get_numeric_typmod_from_exp(NULL, expr);
+				typmod = (*pltsql_protocol_plugin_ptr)->get_numeric_typmod_from_exp(NULL, expr, NULL);
 
 			if (typmod == -1 || getBaseType(type) != NUMERICOID)
 				continue;

test/JDBC/expected/BABEL-1000.out

@@ -162,14 +162,14 @@ SELECT * FROM babel_1000_test8(1)
 GO
 ~~START~~
 numeric
-2.06000000
+2.06
 ~~END~~
 
 SELECT * FROM babel_1000_test8(12.345678)
 GO
 ~~START~~
 numeric
-13.06000000
+13.06
 ~~END~~
 
 -- overflow, expect error

test/JDBC/expected/BABEL-1164.out

@@ -43,7 +43,7 @@ SELECT * FROM t2;
 GO
 ~~START~~
 int#!#int#!#numeric#!#numeric
-1#!#1#!#2#!#2.00000000
+1#!#1#!#2#!#2
 ~~END~~
 
 

test/JDBC/expected/BABEL-3066-vu-verify.out

@@ -504,15 +504,15 @@ SELECT CAST(CAST(12465781.46792 as real) as numeric(38,10)) - CAST(CAST(12465781
 GO
 ~~START~~
 numeric
-0
+0E-15
 ~~END~~
 
 
 SELECT CAST(CAST(12465781.46792 as real) as numeric(38,10)) - CAST(CAST(12465781.4679213254 as real) as numeric(38,10));
 GO
 ~~START~~
 numeric
-0
+0E-10
 ~~END~~
 
 
@@ -540,9 +540,10 @@ GO
 
 SELECT CAST(CAST(12465781.46792 as real) as numeric(38,10)) * CAST(CAST(12465781.4679213254 as real) as numeric(38,15));
 GO
-~~ERROR (Code: 33557097)~~
-
-~~ERROR (Message: Arithmetic overflow error for data type numeric.)~~
+~~START~~
+numeric
+155395695939961.000000
+~~END~~
 
 
 SELECT CAST(CAST(CAST(CAST(12465781.46792 as real) as numeric(38,10)) * CAST(CAST(12465781.4679213254 as real) as numeric(38,15)) as real) as numeric(38,6));
@@ -557,15 +558,15 @@ SELECT CAST(CAST(12465781.46792 as real) as numeric(38,10)) * CAST(CAST(12465781
 GO
 ~~START~~
 numeric
-155395695939961.00000000000000000000
+155395695939961.000000
 ~~END~~
 
 
 SELECT CAST(CAST(12465781.46792 as real) as numeric(38,0)) / CAST(CAST(12465781.4679213254 as real) as numeric(38,0));
 GO
 ~~START~~
 numeric
-1.00000000000000000000
+1.000000
 ~~END~~
 
 
@@ -587,14 +588,14 @@ SELECT CAST(CAST(12465781.46792 as real) as numeric(38,10)) / CAST(CAST(12465781
 GO
 ~~START~~
 numeric
-1.00000000000000000000
+1.000000
 ~~END~~
 
 
 SELECT CAST(CAST(12465781.46792 as real) as numeric(38,10)) / CAST(CAST(12465781.4679213254 as real) as numeric(38,10));
 GO
 ~~START~~
 numeric
-1.00000000000000000000
+1.000000
 ~~END~~
 

test/JDBC/expected/BABEL-381.out

@@ -12,14 +12,14 @@ select 2.0/1.5;
 go
 ~~START~~
 numeric
-1.3333333333333333
+1.333333
 ~~END~~
 
 
 select 2.0, 2.0/1.5, 1.0/1.5;
 go
 ~~START~~
 numeric#!#numeric#!#numeric
-2.0#!#1.3333333333333333#!#0.66666666666666666667
+2.0#!#1.333333#!#0.666666
 ~~END~~