Bug#31931 Partitions: unjustified 'mix of handlers' error message

Problem was that the mix of handlers was not consistent between
CREATE and ALTER

changed so that it works like:
    - All partitions must use the same engine
      AND it must be the same as the table.
    - if one does NOT specify an engine on the table level
      then one must either NOT specify any engine on any
      partition/subpartition OR for ALL partitions/subpartitions

Note: that after a table have been created, the storage engine
is specified for all parts of the table (table/partition/subpartition)
and so when using alter, one does not need to specify it (unless one
wants to change the storage engine, then one have to specify it on the
table level)

1 files changed, 5 insertions, 4 deletions

diff --git a/mysql-test/r/partition_innodb.result b/mysql-test/r/partition_innodb.result
index 5cbe34c94ca..ac9b548b19e 100644
--- a/mysql-test/r/partition_innodb.result
+++ b/mysql-test/r/partition_innodb.result
@@ -79,8 +79,7 @@ engine = innodb
 partition by list (a)
 (partition p0 values in (0));
 alter table t1 engine = x;
-Warnings:
-Warning	1286	Unknown table engine 'x'
+ERROR HY000: The mix of handlers in the partitions is not allowed in this version of MySQL
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
@@ -151,9 +150,11 @@ DROP TABLE t1;
 create table t1 (int_column int, char_column char(5))
 PARTITION BY RANGE (int_column) subpartition by key (char_column) subpartitions 2
 (PARTITION p1 VALUES LESS THAN (5) ENGINE = InnoDB);
-alter table t1 PARTITION BY RANGE (int_column)
+alter table t1
+ENGINE = MyISAM
+PARTITION BY RANGE (int_column)
 subpartition by key (char_column) subpartitions 2
-(PARTITION p1 VALUES LESS THAN (5) ENGINE = myisam);
+(PARTITION p1 VALUES LESS THAN (5));
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (