cstore_test=# select product_group, count(*) from customer_reviews group by product_group;
product_group | count
---------------+---------
DVD | 121418
Video | 142235
Music | 300628
Book | 1198218
Software | 1
CE | 1
Toy | 3
(7 rows)
cstore_test=# EXPLAIN ANALYZE VERBOSE select product_group, count(*) from customer_reviews_cstore group by product_group;
QUERY PLAN
----------------------------------------------------------------------------------------------------------------------------------------
HashAggregate (cost=36258.75..36260.75 rows=200 width=40) (actual time=3358.244..3358.246 rows=7 loops=1)
Output: book.product_group, count(*)
Group Key: book.product_group
-> Append (cost=0.00..27446.23 rows=1762504 width=32) (actual time=0.242..2392.405 rows=1762504 loops=1)
-> Foreign Scan on public.book (cost=0.00..12676.43 rows=1198218 width=32) (actual time=0.241..590.246 rows=1198218 loops=1)
Output: book.product_group
CStore File Size: 68247552
-> Foreign Scan on public.ce (cost=0.00..0.34 rows=1 width=32) (actual time=0.108..0.109 rows=1 loops=1)
Output: ce.product_group
CStore File Size: 32768
-> Foreign Scan on public.dvd (cost=0.00..1281.18 rows=121418 width=32) (actual time=0.201..59.203 rows=121418 loops=1)
Output: dvd.product_group
CStore File Size: 6586368
-> Foreign Scan on public.music (cost=0.00..3172.28 rows=300628 width=32) (actual time=0.293..155.498 rows=300628 loops=1)
Output: music.product_group
CStore File Size: 16318464
-> Foreign Scan on public.software (cost=0.00..0.34 rows=1 width=32) (actual time=0.047..0.048 rows=1 loops=1)
Output: software.product_group
CStore File Size: 32768
-> Foreign Scan on public.toy (cost=0.00..0.36 rows=3 width=32) (actual time=0.045..0.048 rows=3 loops=1)
Output: toy.product_group
CStore File Size: 32768
-> Foreign Scan on public.video (cost=0.00..1502.77 rows=142235 width=32) (actual time=0.221..69.641 rows=142235 loops=1)
Output: video.product_group
CStore File Size: 7905280
Planning Time: 0.806 ms
Execution Time: 3358.408 ms
(27 rows)
# git diff
diff --git a/cstore_fdw.c b/cstore_fdw.c
index fd08621..220806e 100644
--- a/cstore_fdw.c
+++ b/cstore_fdw.c
@@ -149,7 +149,8 @@ static TupleTableSlot * CStoreExecForeignInsert(EState *executorState,
TupleTableSlot *tupleSlot,
TupleTableSlot *planSlot);
static void CStoreEndForeignModify(EState *executorState, ResultRelInfo *relationInfo);
-
+static bool CStoreIsForeignScanParallelSafe(PlannerInfo *root, RelOptInfo *rel,
+ RangeTblEntry *rte);
/* declarations for dynamic loading */
PG_MODULE_MAGIC;
@@ -1191,6 +1192,7 @@ cstore_fdw_handler(PG_FUNCTION_ARGS)
fdwRoutine->BeginForeignModify = CStoreBeginForeignModify;
fdwRoutine->ExecForeignInsert = CStoreExecForeignInsert;
fdwRoutine->EndForeignModify = CStoreEndForeignModify;
+ fdwRoutine->IsForeignScanParallelSafe = CStoreIsForeignScanParallelSafe;
PG_RETURN_POINTER(fdwRoutine);
}
@@ -2234,3 +2236,13 @@ CStoreEndForeignModify(EState *executorState, ResultRelInfo *relationInfo)
}
}
+/*
+ * CStoreIsForeignScanParallelSafe
+ */
+static bool
+CStoreIsForeignScanParallelSafe(PlannerInfo *root, RelOptInfo *rel,
+ RangeTblEntry *rte)
+{
+ return true;
+}
+cstore_test=# select product_group, count(*) from customer_reviews_cstore group by product_group;
product_group | count
---------------+---------
Book | 1198218
CE | 1
DVD | 121418
Music | 300628
Software | 1
Toy | 3
Video | 142235
(7 rows)
cstore_test=# EXPLAIN ANALYZE VERBOSE select product_group, count(*) from customer_reviews_cstore group by product_group;
QUERY PLAN
----------------------------------------------------------------------------------------------------------------------------------------------------------
Finalize GroupAggregate (cost=16350.32..16394.32 rows=200 width=40) (actual time=2486.607..2486.629 rows=7 loops=1)
Output: book.product_group, count(*)
Group Key: book.product_group
-> Gather Merge (cost=16350.32..16392.32 rows=400 width=40) (actual time=2486.591..2486.603 rows=7 loops=1)
Output: book.product_group, (PARTIAL count(*))
Workers Planned: 2
Workers Launched: 2
-> Sort (cost=16350.32..16350.32 rows=200 width=40) (actual time=1294.222..1294.225 rows=2 loops=3)
Output: book.product_group, (PARTIAL count(*))
Sort Key: book.product_group
Sort Method: quicksort Memory: 25kB
Worker 0: Sort Method: quicksort Memory: 25kB
Worker 1: Sort Method: quicksort Memory: 25kB
Worker 0: actual time=2455.745..2455.747 rows=1 loops=1
Worker 1: actual time=746.120..746.121 rows=1 loops=1
-> Partial HashAggregate (cost=16348.32..16350.32 rows=200 width=40) (actual time=1294.154..1294.157 rows=2 loops=3)
Output: book.product_group, PARTIAL count(*)
Group Key: book.product_group
Worker 0: actual time=2455.653..2455.655 rows=1 loops=1
Worker 1: actual time=746.042..746.044 rows=1 loops=1
-> Parallel Append (cost=0.00..16348.32 rows=734377 width=32) (actual time=1.459..922.325 rows=587501 loops=3)
Worker 0: actual time=2.256..1754.035 rows=1198218 loops=1
Worker 1: actual time=1.938..529.985 rows=300628 loops=1
-> Foreign Scan on public.book (cost=0.00..12676.43 rows=1198218 width=32) (actual time=2.253..648.646 rows=1198218 loops=1)
Output: book.product_group
CStore File Size: 68247552
Worker 0: actual time=2.253..648.646 rows=1198218 loops=1
-> Foreign Scan on public.music (cost=0.00..3172.28 rows=300628 width=32) (actual time=1.935..194.581 rows=300628 loops=1)
Output: music.product_group
CStore File Size: 16318464
Worker 1: actual time=1.935..194.581 rows=300628 loops=1
-> Foreign Scan on public.video (cost=0.00..1502.77 rows=142235 width=32) (actual time=2.971..97.716 rows=142235 loops=1)
Output: video.product_group
CStore File Size: 7905280
-> Foreign Scan on public.dvd (cost=0.00..1281.18 rows=121418 width=32) (actual time=0.808..78.930 rows=121418 loops=1)
Output: dvd.product_group
CStore File Size: 6586368
-> Foreign Scan on public.toy (cost=0.00..0.36 rows=3 width=32) (actual time=0.055..0.057 rows=3 loops=1)
Output: toy.product_group
CStore File Size: 32768
-> Foreign Scan on public.ce (cost=0.00..0.34 rows=1 width=32) (actual time=0.053..0.054 rows=1 loops=1)
Output: ce.product_group
CStore File Size: 32768
-> Foreign Scan on public.software (cost=0.00..0.34 rows=1 width=32) (actual time=0.182..0.183 rows=1 loops=1)
Output: software.product_group
CStore File Size: 32768
Planning Time: 11.811 ms
Execution Time: 2491.126 ms
(48 rows)
