From 6e492d2c82be2c7a938c4899c33650bca62e679c Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Thu, 29 Oct 2020 18:36:16 +0800
Subject: [PATCH 1/3] [td-255]

---
 src/tsdb/src/tsdbRead.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/tsdb/src/tsdbRead.c b/src/tsdb/src/tsdbRead.c
index 5b0896ae6f..92305be714 100644
--- a/src/tsdb/src/tsdbRead.c
+++ b/src/tsdb/src/tsdbRead.c
@@ -2121,7 +2121,16 @@ STimeWindow changeTableGroupByLastrow(STableGroupInfo *groupList) {
       }
     }
 
-    // clear current group
+    // clear current group, unref unused table
+    for(int32_t i = 0; i < numOfTables; ++i) {
+      STableKeyInfo* pKeyInfo = (STableKeyInfo*) taosArrayGet(pGroup, i);
+
+      // keyInfo.pTable may be NULL here.
+      if (pKeyInfo->pTable != keyInfo.pTable) {
+        tsdbUnRefTable(pKeyInfo->pTable);
+      }
+    }
+
     taosArrayClear(pGroup);
 
     // more than one table in each group, only one table left for each group

From 16b1e7cbf11ce6e1d101da58dfba337f5dee85cf Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Fri, 30 Oct 2020 10:47:18 +0800
Subject: [PATCH 2/3] [td-255] update sim

---
 .../script/general/parser/join_multivnode.sim | 61 +++++++++++++++++--
 1 file changed, 57 insertions(+), 4 deletions(-)

diff --git a/tests/script/general/parser/join_multivnode.sim b/tests/script/general/parser/join_multivnode.sim
index 5e4a0990c1..0ffb15e022 100644
--- a/tests/script/general/parser/join_multivnode.sim
+++ b/tests/script/general/parser/join_multivnode.sim
@@ -134,13 +134,66 @@ sql select join_mt0.ts, join_mt1.t1, join_mt0.t1, join_mt1.tbname, join_mt0.tbna
 
 #1970-01-01 08:01:40.800 |                    10 |              45.000000000 |         0 |     true |     false |           0 |
 #1970-01-01 08:01:40.790 |                    10 |             945.000000000 |        90 |     true |      true |           0 |
-
 sql select count(join_mt0.c1), sum(join_mt1.c2), first(join_mt0.c5), last(join_mt1.c7), first(join_mt1.c7) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1 order by join_mt0.ts desc limit 20 offset 19;
-if $rows != 100 then
+if $rows != 20 then
   return -1
 endi
 
-# c5 is null ! error
+if $data00 != @70-01-01 08:01:40.800@ then
+  return -1
+endi
+
+if $data01 != 10 then
+  return -1
+endi
+
+if $data02 != 45.000000000 then
+  return -1
+endi
+
+if $data03 != 0 then
+  return -1
+endi
+
+if $data04 != 1 then
+  return -1
+endi
+
+if $data05 != 0 then
+  return -1
+endi
+
+if $data06 != 0 then
+  return -1
+endi
+
+if $data10 != @70-01-01 08:01:40.790@ then
+  return -1
+endi
+
+if $data11 != 10 then
+  return -1
+endi
+
+if $data12 != 945.000000000 then
+  return -1
+endi
+
+if $data13 != 90 then
+  return -1
+endi
+
+if $data14 != 1 then
+  return -1
+endi
+
+if $data15 != 1 then
+  return -1
+endi
+
+if $data16 != 0 then
+  return -1
+endi
 
 sql select count(join_mt0.c1), sum(join_mt0.c2)/count(*), avg(c2), first(join_mt0.c5), last(c7) from join_mt0  interval(10a) group by join_mt0.t1 order by join_mt0.ts desc;
 if $rows != 100 then
@@ -262,4 +315,4 @@ if $data03 != 0 then
   return -1
 endi
 
-system sh/exec.sh -n dnode1 -s stop -x SIGINT
\ No newline at end of file
+#system sh/exec.sh -n dnode1 -s stop -x SIGINT
\ No newline at end of file

From f311440d5d1edd3d8e7f63be41d3c0e79bb55c86 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Fri, 30 Oct 2020 10:49:14 +0800
Subject: [PATCH 3/3] [td-255] update sim

---
 tests/script/general/parser/join_multivnode.sim | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/script/general/parser/join_multivnode.sim b/tests/script/general/parser/join_multivnode.sim
index 0ffb15e022..102d5ba93f 100644
--- a/tests/script/general/parser/join_multivnode.sim
+++ b/tests/script/general/parser/join_multivnode.sim
@@ -315,4 +315,4 @@ if $data03 != 0 then
   return -1
 endi
 
-#system sh/exec.sh -n dnode1 -s stop -x SIGINT
\ No newline at end of file
+system sh/exec.sh -n dnode1 -s stop -x SIGINT
\ No newline at end of file