Fix CAgg on CAgg variable bucket size validation

Previous attempt to fix it (PR #5130) was not entirely correct because
the bucket width calculation for interval width was wrong.

Fixed it by properly calculate the bucket width for intervals using the
Postgres internal function `interval_part` to extract the epoch of the
interval and execute the validations. For integer widths use the already
calculated bucket width.

Fixes #5158, #5168

CHANGELOG.md

@@ -9,14 +9,14 @@ accidentally triggering the load of a previous DB version.**
 **Bugfixes**
 * #4926 Fix corruption when inserting into compressed chunks
 * #5114 Fix issue with deleting data node and dropping database
-* #5130 Fix CAgg on CAgg variable bucket size validation
 * #5133 Fix CAgg on CAgg using different column order on the original hypertable
 * #5152 Fix adding column with NULL constraint to compressed hypertable
+* #5170 Fix CAgg on CAgg variable bucket size validation
 
 **Thanks**
 * @ikkala for reporting error when adding column with NULL constraint to compressed hypertable
 * @salquier-appvizer for reporting error on CAgg on CAgg using different column order on the original hypertable
-* @ssmoss for reporting error on CAgg on CAgg variable bucket size validation
+* @ssmoss, @adbnexxtlab and @ivanzamanov for reporting error on CAgg on CAgg variable bucket size validation
 
 ## 2.9.1 (2022-12-23)
 

tsl/src/continuous_aggs/create.c

@@ -1099,24 +1099,53 @@ cagg_query_supported(const Query *query, StringInfo hint, StringInfo detail, con
 static inline int64
 get_bucket_width(CAggTimebucketInfo bucket_info)
 {
-	if (bucket_info.bucket_width == BUCKET_WIDTH_VARIABLE)
+	int64 width = 0;
+
+	/* calculate the width */
+	switch (bucket_info.bucket_width_type)
 	{
-		/* calculate the width */
-		return ts_interval_value_to_internal(IntervalPGetDatum(bucket_info.interval),
-											 bucket_info.bucket_width_type);
+		case INT8OID:
+		case INT4OID:
+		case INT2OID:
+			width = bucket_info.bucket_width;
+			break;
+		case INTERVALOID:
+		{
+			Datum epoch = DirectFunctionCall2(interval_part,
+											  PointerGetDatum(cstring_to_text("epoch")),
+											  IntervalPGetDatum(bucket_info.interval));
+			/* cast float8 to int8 */
+			width = DatumGetInt64(DirectFunctionCall1(dtoi8, epoch));
+			break;
+		}
+		default:
+			Assert(false);
 	}
 
-	return bucket_info.bucket_width;
+	return width;
 }
 
 static inline Datum
 get_bucket_width_datum(CAggTimebucketInfo bucket_info)
 {
-	if (bucket_info.bucket_width == BUCKET_WIDTH_VARIABLE)
-		return IntervalPGetDatum(bucket_info.interval);
+	Datum width = (Datum) 0;
 
-	return ts_internal_to_interval_value(get_bucket_width(bucket_info),
-										 bucket_info.bucket_width_type);
+	switch (bucket_info.bucket_width_type)
+	{
+		case INT8OID:
+		case INT4OID:
+		case INT2OID:
+			width = ts_internal_to_interval_value(bucket_info.bucket_width,
+												  bucket_info.bucket_width_type);
+			break;
+		case INTERVALOID:
+			width = IntervalPGetDatum(bucket_info.interval);
+			break;
+		default:
+			Assert(false);
+	}
+
+	return width;
 }
 
 static CAggTimebucketInfo
@@ -1320,8 +1349,8 @@ cagg_validate_query(const Query *query, const bool finalized, const char *cagg_s
 	/* nested cagg validations */
 	if (is_nested)
 	{
-		int64 bucket_width, bucket_width_parent;
-		bool is_greater_or_equal_than_parent, is_multiple_of_parent;
+		int64 bucket_width = 0, bucket_width_parent = 0;
+		bool is_greater_or_equal_than_parent = true, is_multiple_of_parent = true;
 
 		Assert(prev_query->groupClause);
 		caggtimebucket_validate(&bucket_info_parent,
@@ -1354,7 +1383,13 @@ cagg_validate_query(const Query *query, const bool finalized, const char *cagg_s
 		is_greater_or_equal_than_parent = (bucket_width >= bucket_width_parent);
 
 		/* check if buckets are multiple */
-		is_multiple_of_parent = ((bucket_width % bucket_width_parent) == 0);
+		if (bucket_width_parent != 0)
+		{
+			if (bucket_width_parent > bucket_width && bucket_width != 0)
+				is_multiple_of_parent = ((bucket_width_parent % bucket_width) == 0);
+			else
+				is_multiple_of_parent = ((bucket_width % bucket_width_parent) == 0);
+		}
 
 		/* proceed with validation errors */
 		if (!is_greater_or_equal_than_parent || !is_multiple_of_parent)
@@ -1373,14 +1408,14 @@ cagg_validate_query(const Query *query, const bool finalized, const char *cagg_s
 			width_parent = get_bucket_width_datum(bucket_info_parent);
 			width_out_parent = DatumGetCString(OidFunctionCall1(outfuncid, width_parent));
 
-			/* new bucket should be greater than the parent */
-			if (!is_greater_or_equal_than_parent)
-				message = "greater than";
-
 			/* new bucket should be multiple of the parent */
 			if (!is_multiple_of_parent)
 				message = "multiple of";
 
+			/* new bucket should be greater than the parent */
+			if (!is_greater_or_equal_than_parent)
+				message = "greater or equal than";
+
 			ereport(ERROR,
 					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 					 errmsg("cannot create continuous aggregate with incompatible bucket width"),