Merge branch 'mysql-5.7-cluster-7.5' into mysql-5.7-cluster-7.6

Change-Id: Ifd0e1f4469b9c4167349e549d6158e17644e4754

Author: arnabray21

mysql-test/suite/ndb/r/ndb_index_stat.result

@@ -662,6 +662,46 @@ select * from information_schema.tables;
 Pattern "\[NdbApi\] ERROR    -- ndb_index_stat key\/value has different length than expected" found
 #cleanup
 drop table t1;
+CREATE TABLE t1 (
+a INT PRIMARY KEY,
+b INT,
+c INT,
+UNIQUE(c)
+) ENGINE NDB PARTITION BY KEY(a);
+Insert 100 rows
+ANALYZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	OK
+SELECT CASE COUNT(*) > 0
+WHEN 1 THEN 'YES' ELSE 'NO' END
+AS stats_metadata_present FROM mysql.ndb_index_stat_head;
+stats_metadata_present
+YES
+SELECT COUNT(*) INTO @samples_pre_alter FROM mysql.ndb_index_stat_sample;
+ALTER TABLE t1 COMMENT="NDB_TABLE=READ_BACKUP=1";
+ANALYZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	OK
+SELECT COUNT(index_id)
+FROM mysql.ndb_index_stat_head
+GROUP BY index_id
+HAVING COUNT(index_id) > 1;
+COUNT(index_id)
+2
+2
+Sample count is the same as before the ALTER
+EXPLAIN is the same both pre- and post-ALTER
+DROP TABLE t1;
+SELECT CASE COUNT(*) > 0
+WHEN 1 THEN 'YES' ELSE 'NO' END
+AS stats_metadata_present FROM mysql.ndb_index_stat_head;
+stats_metadata_present
+YES
+SELECT CASE COUNT(*) = 0
+WHEN 1 THEN 'YES' ELSE 'NO' END
+AS stats_samples_cleaned_up FROM mysql.ndb_index_stat_sample;
+stats_samples_cleaned_up
+YES
 set @is_enable = @is_enable_default;
 set @is_enable = NULL;
 # is_enable_on=0 is_enable_off=0

mysql-test/suite/ndb/t/ndb_index_stat.test

@@ -526,5 +526,92 @@ select * from information_schema.tables;
 --echo #cleanup
 drop table t1;
 
+# Bug#29611297 NDB: INDEX STAT HAS ISSUES WITH ONLINE ALTER TABLE TO/FROM
+# READBACKUP. Online ALTER TABLE statements that resulted in the index
+# version being bumped up left behind orphaned index stats corresponding
+# to the previous index version.
+CREATE TABLE t1 (
+  a INT PRIMARY KEY,
+  b INT,
+  c INT,
+  UNIQUE(c)
+) ENGINE NDB PARTITION BY KEY(a);
+
+--echo Insert 100 rows
+--disable_query_log
+let $i = 100;
+while ($i)
+{
+  dec $i;
+  eval INSERT INTO t1 VALUES($i, $i % 100, $i);
+}
+--enable_query_log
+
+# Trigger index stats creation which creates 1 metadata entry
+# in the head table (exposed to users via the ndbinfo.index_stats
+# table) and n sample table entries per index
+ANALYZE TABLE t1;
+# Uncomment below to check details
+#SELECT * FROM mysql.ndb_index_stat_head;
+SELECT CASE COUNT(*) > 0
+       WHEN 1 THEN 'YES' ELSE 'NO' END
+AS stats_metadata_present FROM mysql.ndb_index_stat_head;
+# Record the number of samples created. This seems to vary across platforms
+SELECT COUNT(*) INTO @samples_pre_alter FROM mysql.ndb_index_stat_sample;
+
+# Record the value of 'rows' in the EXPLAIN output for a later check
+--let $query=SELECT * FROM t1 WHERE c > 50
+--let $explain_rows_pre_alter=query_get_value(EXPLAIN $query, rows, 1)
+
+# Online ALTER that creates indexes with new versions
+ALTER TABLE t1 COMMENT="NDB_TABLE=READ_BACKUP=1";
+
+# Trigger index stats creation. The ANALYZE below will clean up
+# samples corresponding to the old index version in the
+# ndb_index_stat_sample table and create new samples for the
+# new index version.
+ANALYZE TABLE t1;
+# Uncomment below to check details
+#SELECT * FROM mysql.ndb_index_stat_head;
+# Check for duplicates
+SELECT COUNT(index_id)
+FROM mysql.ndb_index_stat_head
+GROUP BY index_id
+HAVING COUNT(index_id) > 1;
+# Should still be 21/26 samples. Was 42/52 (21/26 created with
+# <index_id, old index_version> as the key and 21/26 more
+# with <index_id, new index version>) before the bug fix
+if (`SELECT COUNT(*) <> @samples_pre_alter FROM mysql.ndb_index_stat_sample`)
+{
+  --die "Extra samples found"
+}
+--echo Sample count is the same as before the ALTER
+
+# Execute the same EXPLAIN as earlier. The expectation is that the 'rows'
+# output is the same from before the ALTER
+--let $explain_rows_post_alter=query_get_value(EXPLAIN $query, rows, 1)
+#--expr $explain_rows_change = $explain_rows_post_alter - $explain_rows_pre_alter
+if ($explain_rows_post_alter == $explain_rows_pre_alter)
+{
+  --echo EXPLAIN is the same both pre- and post-ALTER
+}
+if ($explain_rows_post_alter != $explain_rows_pre_alter)
+{
+  --die EXPLAIN has changed. Pre-ALTER: $explain_rows_pre_alter and post-ALTER: $explain_rows_post_alter
+}
+
+DROP TABLE t1;
+
+# We expect 0 entries in the sample table but "stale" metadata
+# info is still present in the head table
+# Uncomment below to check details
+#SELECT * FROM mysql.ndb_index_stat_head;
+SELECT CASE COUNT(*) > 0
+       WHEN 1 THEN 'YES' ELSE 'NO' END
+AS stats_metadata_present FROM mysql.ndb_index_stat_head;
+SELECT CASE COUNT(*) = 0
+       WHEN 1 THEN 'YES' ELSE 'NO' END
+AS stats_samples_cleaned_up FROM mysql.ndb_index_stat_sample;
+
 set @is_enable = @is_enable_default;
 source ndb_index_stat_enable.inc;

storage/ndb/src/kernel/blocks/trix/Trix.cpp

@@ -2678,35 +2678,44 @@ Trix::statCleanPrepare(Signal* signal, StatOp& stat)
   ndbrequire(ao_buf.isEmpty());
   ao_buf.append(ao_list, ao_size);
 
-  // create TUX bounds
-  clean.m_bound[0] = TuxBoundInfo::BoundEQ;
-  clean.m_bound[1] = AttributeHeader(0, 4).m_value;
-  clean.m_bound[2] = data.m_indexId;
-  clean.m_bound[3] = TuxBoundInfo::BoundEQ;
-  clean.m_bound[4] = AttributeHeader(1, 4).m_value;
-  clean.m_bound[5] = data.m_indexVersion;
-  Uint32 boundCount;
+  Uint32 boundCount = 0;
   switch (stat.m_requestType) {
   case IndexStatReq::RT_CLEAN_NEW:
     D("statCleanPrepare delete sample versions > " << data.m_sampleVersion);
+    clean.m_bound[0] = TuxBoundInfo::BoundEQ;
+    clean.m_bound[1] = AttributeHeader(0, 4).m_value;
+    clean.m_bound[2] = data.m_indexId;
+    clean.m_bound[3] = TuxBoundInfo::BoundEQ;
+    clean.m_bound[4] = AttributeHeader(1, 4).m_value;
+    clean.m_bound[5] = data.m_indexVersion;
     clean.m_bound[6] = TuxBoundInfo::BoundLT;
     clean.m_bound[7] = AttributeHeader(2, 4).m_value;
     clean.m_bound[8] = data.m_sampleVersion;
     boundCount = 3;
     break;
   case IndexStatReq::RT_CLEAN_OLD:
     D("statCleanPrepare delete sample versions < " << data.m_sampleVersion);
+    clean.m_bound[0] = TuxBoundInfo::BoundEQ;
+    clean.m_bound[1] = AttributeHeader(0, 4).m_value;
+    clean.m_bound[2] = data.m_indexId;
+    clean.m_bound[3] = TuxBoundInfo::BoundEQ;
+    clean.m_bound[4] = AttributeHeader(1, 4).m_value;
+    clean.m_bound[5] = data.m_indexVersion;
     clean.m_bound[6] = TuxBoundInfo::BoundGT;
     clean.m_bound[7] = AttributeHeader(2, 4).m_value;
     clean.m_bound[8] = data.m_sampleVersion;
     boundCount = 3;
     break;
   case IndexStatReq::RT_CLEAN_ALL:
-    D("statCleanPrepare delete all sample versions");
-    boundCount = 2;
+    D("statCleanPrepare delete all sample versions and index versions");
+    // Delete all entries corresponding to the index id. This handles
+    // scenarios involving index versions bumps as well
+    clean.m_bound[0] = TuxBoundInfo::BoundEQ;
+    clean.m_bound[1] = AttributeHeader(0, 4).m_value;
+    clean.m_bound[2] = data.m_indexId;
+    boundCount = 1;
     break;
   default:
-    boundCount = 0; /* Silence compiler warning */
     ndbrequire(false);
     return; /* Silence compiler warning */
     break;
@@ -2755,7 +2764,7 @@ Trix::statCleanExecute(Signal* signal, StatOp& stat)
   ndbrequire(ptr1.sz <= avmax);
   ::copy(av, ptr1);
   ndbrequire(data.m_indexId == av[0]);
-  ndbrequire(data.m_indexVersion == av[1]);
+  data.m_indexVersion = av[1];
   data.m_sampleVersion = av[2];
   data.m_statKey = &av[3];
   const unsigned char* kp = (const unsigned char*)data.m_statKey;