Add hypertable cache lookup on ID/pkey

Hypertables can now be looked up through the cache on
ID/pkey in addition to OID.

Author: erimatnor

src/hypertable.c

@@ -32,6 +32,47 @@ hypertable_from_tuple(HeapTuple tuple)
 	return h;
 }
 
+static bool
+hypertable_tuple_get_relid(TupleInfo *ti, void *data)
+{
+	FormData_hypertable *form = (FormData_hypertable *) GETSTRUCT(ti->tuple);
+	Oid		   *relid = data;
+	Oid			schema_oid = get_namespace_oid(NameStr(form->schema_name), true);
+
+	if (OidIsValid(schema_oid))
+		*relid = get_relname_relid(NameStr(form->table_name), schema_oid);
+
+	return false;
+}
+
+Oid
+hypertable_id_to_relid(int32 hypertable_id)
+{
+	Catalog    *catalog = catalog_get();
+	Oid			relid = InvalidOid;
+	ScanKeyData scankey[1];
+	ScannerCtx	scanctx = {
+		.table = catalog->tables[HYPERTABLE].id,
+		.index = catalog->tables[HYPERTABLE].index_ids[HYPERTABLE_ID_INDEX],
+		.scantype = ScannerTypeIndex,
+		.nkeys = 1,
+		.scankey = scankey,
+		.tuple_found = hypertable_tuple_get_relid,
+		.data = &relid,
+		.lockmode = AccessShareLock,
+		.scandirection = ForwardScanDirection,
+	};
+
+	/* Perform an index scan on the hypertable pkey. */
+	ScanKeyInit(&scankey[0], Anum_hypertable_pkey_idx_id,
+				BTEqualStrategyNumber, F_INT4EQ,
+				Int32GetDatum(hypertable_id));
+
+	scanner_scan(&scanctx);
+
+	return relid;
+}
+
 typedef struct ChunkCacheEntry
 {
 	MemoryContext mcxt;

src/hypertable.h

@@ -22,6 +22,7 @@ typedef struct Hypertable
 extern Hypertable *hypertable_from_tuple(HeapTuple tuple);
 extern int	hypertable_set_name(Hypertable *ht, const char *newname);
 extern int	hypertable_set_schema(Hypertable *ht, const char *newname);
+extern Oid	hypertable_id_to_relid(int32 hypertable_id);
 extern Chunk *hypertable_get_chunk(Hypertable *h, Point *point);
 extern Oid	hypertable_relid(RangeVar *rv);
 extern bool is_hypertable(Oid relid);

src/hypertable_cache.c

@@ -65,7 +65,6 @@ hypertable_cache_create()
 	return cache;
 }
 
-
 static Cache *hypertable_cache_current = NULL;
 
 static bool
@@ -83,7 +82,6 @@ hypertable_cache_create_entry(Cache *cache, CacheQuery *query)
 	HypertableCacheQuery *hq = (HypertableCacheQuery *) query;
 	Catalog    *catalog = catalog_get();
 	HypertableNameCacheEntry *cache_entry = query->result;
-	Hypertable *ht;
 	int			number_found;
 	ScanKeyData scankey[2];
 	ScannerCtx	scanCtx = {
@@ -123,8 +121,6 @@ hypertable_cache_create_entry(Cache *cache, CacheQuery *query)
 		case 1:
 			Assert(strncmp(cache_entry->hypertable->fd.schema_name.data, hq->schema, NAMEDATALEN) == 0);
 			Assert(strncmp(cache_entry->hypertable->fd.table_name.data, hq->table, NAMEDATALEN) == 0);
-			ht = cache_entry->hypertable;
-			ht->space = dimension_scan(ht->fd.id, ht->main_table_relid, ht->fd.num_dimensions);
 			break;
 		default:
 			elog(ERROR, "Got an unexpected number of records: %d", number_found);
@@ -158,6 +154,12 @@ hypertable_cache_get_entry_rv(Cache *cache, RangeVar *rv)
 	return hypertable_cache_get_entry(cache, RangeVarGetRelid(rv, NoLock, true));
 }
 
+Hypertable *
+hypertable_cache_get_entry_by_id(Cache *cache, int32 hypertable_id)
+{
+	return hypertable_cache_get_entry(cache, hypertable_id_to_relid(hypertable_id));
+}
+
 Hypertable *
 hypertable_cache_get_entry_with_table(Cache *cache, Oid relid, const char *schema, const char *table)
 {

src/hypertable_cache.h

@@ -8,6 +8,7 @@
 extern Hypertable *hypertable_cache_get_entry(Cache *cache, Oid relid);
 extern Hypertable *hypertable_cache_get_entry_rv(Cache *cache, RangeVar *rv);
 extern Hypertable *hypertable_cache_get_entry_with_table(Cache *cache, Oid relid, const char *schema, const char *table);
+extern Hypertable *hypertable_cache_get_entry_by_id(Cache *cache, int32 hypertable_id);
 
 extern void hypertable_cache_invalidate_callback(void);