MDEV-14026 ALTER TABLE ... DELAY_KEY_WRITE=1 creates table copy for partitioned MyISAM table with DATA DIRECTORY/INDEX DIRECTORY options

set data_file_name and index_file_name in HA_CREATE_INFO
before calling check_if_incompatible_data()

4 files changed, 57 insertions, 13 deletions

diff --git a/mysql-test/r/partition_windows.result b/mysql-test/r/partition_windows.result
index dabcedcb3f9..756690925f8 100644
--- a/mysql-test/r/partition_windows.result
+++ b/mysql-test/r/partition_windows.result
@@ -26,9 +26,5 @@ ALTER TABLE t1 ADD PARTITION (PARTITION p3 DATA DIRECTORY = 'G:/mysqltest/p3Data
 Warnings:
 Warning	1618	<DATA DIRECTORY> option ignored
 Warning	1618	<INDEX DIRECTORY> option ignored
-Warning	1618	<DATA DIRECTORY> option ignored
-Warning	1618	<INDEX DIRECTORY> option ignored
-Warning	1618	<DATA DIRECTORY> option ignored
-Warning	1618	<INDEX DIRECTORY> option ignored
 INSERT INTO t1 VALUES (NULL, "last", 4);
 DROP TABLE t1;
diff --git a/mysql-test/suite/parts/r/partition_alter_myisam.result b/mysql-test/suite/parts/r/partition_alter_myisam.result
index 9f2381039d3..41af6af72fc 100644
--- a/mysql-test/suite/parts/r/partition_alter_myisam.result
+++ b/mysql-test/suite/parts/r/partition_alter_myisam.result
@@ -42,3 +42,16 @@ PARTITION p3 VALUES IN (4,5,6)
 );
 ERROR HY000: Syntax error: LIST PARTITIONING requires definition of VALUES IN for each partition
 DROP TABLE t1;
+create table t1 ( c1 int, c2 int, c3 varchar(100)) delay_key_write=1
+partition by key(c1) (
+partition p01 data directory = 'MYSQL_TMP_DIR'
+                 index directory = 'MYSQL_TMP_DIR',
+partition p02 data directory = 'MYSQL_TMP_DIR'
+                 index directory = 'MYSQL_TMP_DIR');
+insert into t1 values (1, 1, repeat('a', 100));
+insert into t1 select rand()*1000, rand()*1000, repeat('b', 100) from t1;
+insert into t1 select rand()*1000, rand()*1000, repeat('b', 100) from t1;
+insert into t1 select rand()*1000, rand()*1000, repeat('b', 100) from t1;
+alter online table t1 delay_key_write=0;
+alter online table t1 delay_key_write=1;
+drop table t1;
diff --git a/mysql-test/suite/parts/t/partition_alter_myisam.test b/mysql-test/suite/parts/t/partition_alter_myisam.test
index a53fa333abd..b2bd0e72e4c 100644
--- a/mysql-test/suite/parts/t/partition_alter_myisam.test
+++ b/mysql-test/suite/parts/t/partition_alter_myisam.test
@@ -1,3 +1,22 @@
 --source include/have_partition.inc
 --let $engine=MyISAM
 --source inc/part_alter_values.inc
+
+#
+# MDEV-14026 ALTER TABLE ... DELAY_KEY_WRITE=1 creates table copy for partitioned MyISAM table with DATA DIRECTORY/INDEX DIRECTORY options
+#
+
+replace_result $MYSQL_TMP_DIR MYSQL_TMP_DIR;
+eval create table t1 ( c1 int, c2 int, c3 varchar(100)) delay_key_write=1
+  partition by key(c1) (
+    partition p01 data directory = '$MYSQL_TMP_DIR'
+                 index directory = '$MYSQL_TMP_DIR',
+    partition p02 data directory = '$MYSQL_TMP_DIR'
+                 index directory = '$MYSQL_TMP_DIR');
+insert into t1 values (1, 1, repeat('a', 100));
+insert into t1 select rand()*1000, rand()*1000, repeat('b', 100) from t1;
+insert into t1 select rand()*1000, rand()*1000, repeat('b', 100) from t1;
+insert into t1 select rand()*1000, rand()*1000, repeat('b', 100) from t1;
+alter online table t1 delay_key_write=0;
+alter online table t1 delay_key_write=1;
+drop table t1;
diff --git a/sql/ha_partition.cc b/sql/ha_partition.cc
index 459af18f737..34c253cc48a 100644
--- a/sql/ha_partition.cc
+++ b/sql/ha_partition.cc
@@ -8133,20 +8133,36 @@ uint ha_partition::alter_table_flags(uint flags)
 bool ha_partition::check_if_incompatible_data(HA_CREATE_INFO *create_info,
                                               uint table_changes)
 {
-  handler **file;
-  bool ret= COMPATIBLE_DATA_YES;
-
   /*
     The check for any partitioning related changes have already been done
     in mysql_alter_table (by fix_partition_func), so it is only up to
     the underlying handlers.
   */
-  for (file= m_file; *file; file++)
-    if ((ret=  (*file)->check_if_incompatible_data(create_info,
-                                                   table_changes)) !=
-        COMPATIBLE_DATA_YES)
-      break;
-  return ret;
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  HA_CREATE_INFO dummy_info= *create_info;
+  uint i=0;
+  while (partition_element *part_elem= part_it++)
+  {
+    if (m_is_sub_partitioned)
+    {
+      List_iterator<partition_element> subpart_it(part_elem->subpartitions);
+      while (partition_element *sub_elem= subpart_it++)
+      {
+        dummy_info.data_file_name= sub_elem->data_file_name;
+        dummy_info.index_file_name= sub_elem->index_file_name;
+        if (m_file[i++]->check_if_incompatible_data(&dummy_info, table_changes))
+          return COMPATIBLE_DATA_NO;
+      }
+    }
+    else
+    {
+      dummy_info.data_file_name= part_elem->data_file_name;
+      dummy_info.index_file_name= part_elem->index_file_name;
+      if (m_file[i++]->check_if_incompatible_data(&dummy_info, table_changes))
+        return COMPATIBLE_DATA_NO;
+    }
+  }
+  return COMPATIBLE_DATA_YES;
 }