diff --git a/mysql-test/r/partition_error.result b/mysql-test/r/partition_error.result
index b692203823d..6ebf033adb7 100644
--- a/mysql-test/r/partition_error.result
+++ b/mysql-test/r/partition_error.result
@@ -1,4 +1,46 @@
 drop table if exists t1;
+#
+# Bug#50392: insert_id is not reset for partitioned tables
+#            auto_increment on duplicate entry
+CREATE TABLE t1 (a INT AUTO_INCREMENT PRIMARY KEY);
+SET INSERT_ID= 13;
+INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID= 12;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+ERROR 23000: Duplicate entry '13' for key 'PRIMARY'
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) NOT NULL AUTO_INCREMENT,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM AUTO_INCREMENT=14 DEFAULT CHARSET=latin1
+INSERT INTO t1 VALUES (NULL);
+SELECT * FROM t1;
+a
+12
+13
+14
+DROP TABLE t1;
+CREATE TABLE t1 (a INT AUTO_INCREMENT PRIMARY KEY) PARTITION BY KEY(a);
+SET INSERT_ID= 13;
+INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID= 12;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+ERROR 23000: Duplicate entry '13' for key 'PRIMARY'
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) NOT NULL AUTO_INCREMENT,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM AUTO_INCREMENT=14 DEFAULT CHARSET=latin1
+/*!50100 PARTITION BY KEY (a) */
+INSERT INTO t1 VALUES (NULL);
+SELECT * FROM t1;
+a
+12
+13
+14
+DROP TABLE t1;
 CREATE TABLE t1 (a INTEGER NOT NULL, PRIMARY KEY (a));
 INSERT INTO t1 VALUES (1),(1);
 ERROR 23000: Duplicate entry '1' for key 'PRIMARY'
diff --git a/mysql-test/suite/parts/inc/partition_auto_increment.inc b/mysql-test/suite/parts/inc/partition_auto_increment.inc
index 2c615e58ef9..102e57d3d04 100644
--- a/mysql-test/suite/parts/inc/partition_auto_increment.inc
+++ b/mysql-test/suite/parts/inc/partition_auto_increment.inc
@@ -42,6 +42,15 @@ if ($mysql_errno)
 INSERT INTO t1 VALUES (NULL);
 SET INSERT_ID = 30;
 INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID = 29;
+-- error 0, ER_DUP_ENTRY, ER_DUP_KEY
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+if (!$mysql_errno)
+{
+  echo # ERROR (only OK if Blackhole) should give ER_DUP_KEY or ER_DUP_ENTRY;
+  echo # mysql_errno: $mysql_errno;
+}
+INSERT INTO t1 VALUES (NULL);
 if (!$skip_update)
 {
 # InnoDB Does not handle this correctly, see bug#14793, bug#21641
@@ -601,6 +610,15 @@ SET INSERT_ID = 23;
 SHOW CREATE TABLE t1;
 INSERT INTO t1 (c1) VALUES (NULL);
 SHOW CREATE TABLE t1;
+SET INSERT_ID = 22;
+-- error 0, ER_DUP_ENTRY, ER_DUP_KEY
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+if (!$mysql_errno)
+{
+  echo # ERROR (only OK if Blackhole) should give ER_DUP_KEY or ER_DUP_ENTRY;
+  echo # mysql_errno: $mysql_errno;
+}
+INSERT INTO t1 VALUES (NULL);
 SELECT * FROM t1 ORDER BY c1;
 DROP TABLE t1;
 
diff --git a/mysql-test/suite/parts/r/partition_auto_increment_archive.result b/mysql-test/suite/parts/r/partition_auto_increment_archive.result
index beda861425c..f62e4aa005a 100644
--- a/mysql-test/suite/parts/r/partition_auto_increment_archive.result
+++ b/mysql-test/suite/parts/r/partition_auto_increment_archive.result
@@ -34,6 +34,9 @@ INSERT INTO t1 VALUES (NULL), (10), (NULL);
 INSERT INTO t1 VALUES (NULL);
 SET INSERT_ID = 30;
 INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID = 29;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 SELECT * FROM t1 ORDER BY c1;
 c1
 2
@@ -46,6 +49,7 @@ c1
 21
 22
 30
+31
 DROP TABLE t1;
 CREATE TABLE t1 (
 c1 INT NOT NULL AUTO_INCREMENT,
@@ -751,10 +755,15 @@ t1	CREATE TABLE `t1` (
 ) ENGINE=ARCHIVE AUTO_INCREMENT=24 DEFAULT CHARSET=latin1
 /*!50100 PARTITION BY HASH (c1)
 PARTITIONS 2 */
+SET INSERT_ID = 22;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 SELECT * FROM t1 ORDER BY c1;
 c1
 1
+22
 23
+24
 DROP TABLE t1;
 # Testing with FLUSH TABLE
 CREATE TABLE t1 (
diff --git a/mysql-test/suite/parts/r/partition_auto_increment_blackhole.result b/mysql-test/suite/parts/r/partition_auto_increment_blackhole.result
index 7ef5ff88499..d6ea8ba0fe4 100644
--- a/mysql-test/suite/parts/r/partition_auto_increment_blackhole.result
+++ b/mysql-test/suite/parts/r/partition_auto_increment_blackhole.result
@@ -35,6 +35,11 @@ INSERT INTO t1 VALUES (NULL), (10), (NULL);
 INSERT INTO t1 VALUES (NULL);
 SET INSERT_ID = 30;
 INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID = 29;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+# ERROR (only OK if Blackhole) should give ER_DUP_KEY or ER_DUP_ENTRY
+# mysql_errno: 0
+INSERT INTO t1 VALUES (NULL);
 UPDATE t1 SET c1 = 50 WHERE c1 = 17;
 UPDATE t1 SET c1 = 51 WHERE c1 = 19;
 FLUSH TABLES;
@@ -597,6 +602,11 @@ t1	CREATE TABLE `t1` (
 ) ENGINE=BLACKHOLE AUTO_INCREMENT=24 DEFAULT CHARSET=latin1
 /*!50100 PARTITION BY HASH (c1)
 PARTITIONS 2 */
+SET INSERT_ID = 22;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+# ERROR (only OK if Blackhole) should give ER_DUP_KEY or ER_DUP_ENTRY
+# mysql_errno: 0
+INSERT INTO t1 VALUES (NULL);
 SELECT * FROM t1 ORDER BY c1;
 c1
 DROP TABLE t1;
diff --git a/mysql-test/suite/parts/r/partition_auto_increment_innodb.result b/mysql-test/suite/parts/r/partition_auto_increment_innodb.result
index 6295d14d98f..4cd7aa57417 100644
--- a/mysql-test/suite/parts/r/partition_auto_increment_innodb.result
+++ b/mysql-test/suite/parts/r/partition_auto_increment_innodb.result
@@ -33,6 +33,9 @@ INSERT INTO t1 VALUES (NULL), (10), (NULL);
 INSERT INTO t1 VALUES (NULL);
 SET INSERT_ID = 30;
 INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID = 29;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 UPDATE t1 SET c1 = 50 WHERE c1 = 17;
 UPDATE t1 SET c1 = 51 WHERE c1 = 19;
 FLUSH TABLES;
@@ -40,7 +43,7 @@ UPDATE t1 SET c1 = 40 WHERE c1 = 50;
 SELECT AUTO_INCREMENT FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA='test'
   AND TABLE_NAME='t1';
 AUTO_INCREMENT
-31
+32
 UPDATE t1 SET c1 = NULL WHERE c1 = 4;
 Warnings:
 Warning	1048	Column 'c1' cannot be null
@@ -60,6 +63,7 @@ c1
 30
 31
 32
+33
 40
 51
 DROP TABLE t1;
@@ -771,10 +775,14 @@ t1	CREATE TABLE `t1` (
 ) ENGINE=InnoDB AUTO_INCREMENT=24 DEFAULT CHARSET=latin1
 /*!50100 PARTITION BY HASH (c1)
 PARTITIONS 2 */
+SET INSERT_ID = 22;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 SELECT * FROM t1 ORDER BY c1;
 c1
 1
 23
+24
 DROP TABLE t1;
 # Testing with FLUSH TABLE
 CREATE TABLE t1 (
diff --git a/mysql-test/suite/parts/r/partition_auto_increment_memory.result b/mysql-test/suite/parts/r/partition_auto_increment_memory.result
index 6e3b990dc0f..1a27d1c2e52 100644
--- a/mysql-test/suite/parts/r/partition_auto_increment_memory.result
+++ b/mysql-test/suite/parts/r/partition_auto_increment_memory.result
@@ -33,6 +33,9 @@ INSERT INTO t1 VALUES (NULL), (10), (NULL);
 INSERT INTO t1 VALUES (NULL);
 SET INSERT_ID = 30;
 INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID = 29;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 UPDATE t1 SET c1 = 50 WHERE c1 = 17;
 UPDATE t1 SET c1 = 51 WHERE c1 = 19;
 FLUSH TABLES;
@@ -57,7 +60,9 @@ c1
 21
 22
 23
+29
 30
+31
 40
 51
 52
@@ -797,10 +802,15 @@ t1	CREATE TABLE `t1` (
 ) ENGINE=MEMORY AUTO_INCREMENT=24 DEFAULT CHARSET=latin1
 /*!50100 PARTITION BY HASH (c1)
 PARTITIONS 2 */
+SET INSERT_ID = 22;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 SELECT * FROM t1 ORDER BY c1;
 c1
 1
+22
 23
+24
 DROP TABLE t1;
 # Testing with FLUSH TABLE
 CREATE TABLE t1 (
diff --git a/mysql-test/suite/parts/r/partition_auto_increment_myisam.result b/mysql-test/suite/parts/r/partition_auto_increment_myisam.result
index 047b974f0a3..9885c78a921 100644
--- a/mysql-test/suite/parts/r/partition_auto_increment_myisam.result
+++ b/mysql-test/suite/parts/r/partition_auto_increment_myisam.result
@@ -33,6 +33,9 @@ INSERT INTO t1 VALUES (NULL), (10), (NULL);
 INSERT INTO t1 VALUES (NULL);
 SET INSERT_ID = 30;
 INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID = 29;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 UPDATE t1 SET c1 = 50 WHERE c1 = 17;
 UPDATE t1 SET c1 = 51 WHERE c1 = 19;
 FLUSH TABLES;
@@ -57,7 +60,9 @@ c1
 21
 22
 23
+29
 30
+31
 40
 51
 52
@@ -816,10 +821,15 @@ t1	CREATE TABLE `t1` (
 ) ENGINE=MyISAM AUTO_INCREMENT=24 DEFAULT CHARSET=latin1
 /*!50100 PARTITION BY HASH (c1)
 PARTITIONS 2 */
+SET INSERT_ID = 22;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 SELECT * FROM t1 ORDER BY c1;
 c1
 1
+22
 23
+24
 DROP TABLE t1;
 # Testing with FLUSH TABLE
 CREATE TABLE t1 (
diff --git a/mysql-test/suite/parts/r/partition_auto_increment_ndb.result b/mysql-test/suite/parts/r/partition_auto_increment_ndb.result
index 317669be7ad..40387b9777a 100644
--- a/mysql-test/suite/parts/r/partition_auto_increment_ndb.result
+++ b/mysql-test/suite/parts/r/partition_auto_increment_ndb.result
@@ -34,6 +34,9 @@ INSERT INTO t1 VALUES (NULL), (10), (NULL);
 INSERT INTO t1 VALUES (NULL);
 SET INSERT_ID = 30;
 INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID = 29;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 UPDATE t1 SET c1 = 50 WHERE c1 = 17;
 UPDATE t1 SET c1 = 51 WHERE c1 = 19;
 FLUSH TABLES;
@@ -58,6 +61,7 @@ c1
 21
 22
 23
+24
 30
 40
 51
@@ -792,9 +796,13 @@ t1	CREATE TABLE `t1` (
 ) ENGINE=ndbcluster DEFAULT CHARSET=latin1
 /*!50100 PARTITION BY HASH (c1)
 PARTITIONS 2 */
+SET INSERT_ID = 22;
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+INSERT INTO t1 VALUES (NULL);
 SELECT * FROM t1 ORDER BY c1;
 c1
 1
+2
 23
 DROP TABLE t1;
 # Testing with FLUSH TABLE
diff --git a/mysql-test/t/partition_error.test b/mysql-test/t/partition_error.test
index 1f011f36257..8da8f54b774 100644
--- a/mysql-test/t/partition_error.test
+++ b/mysql-test/t/partition_error.test
@@ -8,6 +8,30 @@
 drop table if exists t1;
 --enable_warnings
  
+--echo #
+--echo # Bug#50392: insert_id is not reset for partitioned tables
+--echo #            auto_increment on duplicate entry
+CREATE TABLE t1 (a INT AUTO_INCREMENT PRIMARY KEY);
+SET INSERT_ID= 13;
+INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID= 12;
+--error ER_DUP_ENTRY
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+SHOW CREATE TABLE t1;
+INSERT INTO t1 VALUES (NULL);
+SELECT * FROM t1;
+DROP TABLE t1;
+CREATE TABLE t1 (a INT AUTO_INCREMENT PRIMARY KEY) PARTITION BY KEY(a);
+SET INSERT_ID= 13;
+INSERT INTO t1 VALUES (NULL);
+SET INSERT_ID= 12;
+--error ER_DUP_ENTRY
+INSERT INTO t1 VALUES (NULL), (NULL), (NULL);
+SHOW CREATE TABLE t1;
+INSERT INTO t1 VALUES (NULL);
+SELECT * FROM t1;
+DROP TABLE t1;
+
 #
 # Bug#38719: Partitioning returns a different error code for a
 # duplicate key error
diff --git a/sql/ha_partition.cc b/sql/ha_partition.cc
index e7f74ffa37f..4523d620821 100644
--- a/sql/ha_partition.cc
+++ b/sql/ha_partition.cc
@@ -6455,9 +6455,22 @@ void ha_partition::release_auto_increment()
     ulonglong next_auto_inc_val;
     lock_auto_increment();
     next_auto_inc_val= ha_data->next_auto_inc_val;
+    /*
+      If the current auto_increment values is lower than the reserved
+      value, and the reserved value was reserved by this thread,
+      we can lower the reserved value.
+    */
     if (next_insert_id < next_auto_inc_val &&
         auto_inc_interval_for_cur_row.maximum() >= next_auto_inc_val)
-      ha_data->next_auto_inc_val= next_insert_id;
+    {
+      THD *thd= ha_thd();
+      /*
+        Check that we do not lower the value because of a failed insert
+        with SET INSERT_ID, i.e. forced/non generated values.
+      */
+      if (thd->auto_inc_intervals_forced.maximum() < next_insert_id)
+        ha_data->next_auto_inc_val= next_insert_id;
+    }
     DBUG_PRINT("info", ("ha_data->next_auto_inc_val: %lu",
                         (ulong) ha_data->next_auto_inc_val));