Bug#39372 "Smart" ALTER TABLE not so smart after all.

The problem was that PACK_KEYS and MAX_ROWS clause in ALTER TABLE did not trigger
table reconstruction.
The fix is to rebuild a table if PACK_KEYS or MAX_ROWS are specified.


mysql-test/r/alter_table.result:
  test result
mysql-test/t/alter_table.test:
  test case
sql/sql_table.cc:
  The problem was that PACK_KEYS and MAX_ROWS clause in ALTER TABLE did not trigger
  table reconstruction.
  The fix is to rebuild a table if PACK_KEYS or MAX_ROWS are specified.

1 files changed, 30 insertions, 0 deletions

diff --git a/mysql-test/t/alter_table.test b/mysql-test/t/alter_table.test
index 662f9095810..8502ba3f3d3 100644
--- a/mysql-test/t/alter_table.test
+++ b/mysql-test/t/alter_table.test
@@ -947,4 +947,34 @@ ALTER TABLE t1 CHANGE d c varchar(10);
 --disable_info
 DROP TABLE t1;
 
+#
+# Bug#39372 "Smart" ALTER TABLE not so smart after all.
+#
+create table t1(f1 int not null, f2 int not null, key  (f1), key (f2));
+let $count= 50;
+--disable_query_log
+while ($count)
+{
+  EVAL insert into t1 values (1,1),(1,1),(1,1),(1,1),(1,1);
+  EVAL insert into t1 values (2,2),(2,2),(2,2),(2,2),(2,2);
+  dec $count ;
+}
+--enable_query_log
+
+select index_length into @unpaked_keys_size from
+information_schema.tables where table_name='t1';
+alter table t1 pack_keys=1;
+select index_length into @paked_keys_size from
+information_schema.tables where table_name='t1';
+select (@unpaked_keys_size > @paked_keys_size);
+
+select max_data_length into @orig_max_data_length from
+information_schema.tables where table_name='t1';
+alter table t1 max_rows=100;
+select max_data_length into @changed_max_data_length from
+information_schema.tables where table_name='t1';
+select (@orig_max_data_length > @changed_max_data_length);
+
+drop table t1;
+
 --echo End of 5.1 tests