Allow multiple size function calls per query

src/backend/distributed/master/master_metadata_utility.c

@@ -214,6 +214,7 @@ DistributedTableSizeOnWorker(WorkerNode *workerNode, Oid relationId, char *sizeQ
 	PGresult *result = NULL;
 	int queryResult = 0;
 	List *sizeList = NIL;
+	bool raiseErrors = true;
 
 	List *shardIntervalsOnNode = ShardIntervalsOnWorkerGroup(workerNode, relationId);
 
@@ -235,6 +236,8 @@ DistributedTableSizeOnWorker(WorkerNode *workerNode, Oid relationId, char *sizeQ
 	tableSizeString = tableSizeStringInfo->data;
 	tableSize = atol(tableSizeString);
 
+	ClearResults(connection, raiseErrors);
+
 	return tableSize;
 }
 

src/test/regress/expected/multi_size_queries.out

@@ -49,6 +49,15 @@ SELECT citus_total_relation_size('customer_copy_hash');
                    1597440
 (1 row)
 
+-- Make sure we can get multiple sizes in a single query
+SELECT citus_table_size('customer_copy_hash'),
+       citus_table_size('customer_copy_hash'),
+       citus_table_size('supplier');
+ citus_table_size | citus_table_size | citus_table_size 
+------------------+------------------+------------------
+           548864 |           548864 |           401408
+(1 row)
+
 CREATE INDEX index_1 on customer_copy_hash(c_custkey);
 VACUUM (FULL) customer_copy_hash;
 -- Tests on distributed table with index.

src/test/regress/sql/multi_size_queries.sql

@@ -32,6 +32,11 @@ SELECT citus_table_size('customer_copy_hash');
 SELECT citus_relation_size('customer_copy_hash');
 SELECT citus_total_relation_size('customer_copy_hash');
 
+-- Make sure we can get multiple sizes in a single query
+SELECT citus_table_size('customer_copy_hash'),
+       citus_table_size('customer_copy_hash'),
+       citus_table_size('supplier');
+
 CREATE INDEX index_1 on customer_copy_hash(c_custkey);
 VACUUM (FULL) customer_copy_hash;