MDEV-27581 Wrong result with DESC key on partitioned Spider table

take descending indexes into account when generating a query

also fixes MDEV-27617

mysql-test/main/myisam.result

@@ -2796,5 +2796,17 @@ hex(c)	c	i
 C3A4	ä	1
 drop table t;
 #
+# MDEV-27617 HANDLER KEY > (x) does not work with DESC keys, Spider is affected and returns wrong results
+#
+create table t (a int, b char(1), primary key(a desc)) engine=myisam;
+insert into t VALUES (1,'f'),(2,'g'),(3,'j'), (4,'i'),(5,'h');
+handler t open;
+# MUST return 2,'g'. '>' always means READ_AFTER_KEY. desc or not.
+handler t read `primary` > (3);
+a	b
+2	g
+handler t close;
+drop table t;
+#
 # End of 10.8 tests
 #

mysql-test/main/myisam.test

@@ -1895,6 +1895,17 @@ insert into t (c) values ('ä'),('a');
 select hex(c),c,i from t order by c, i;
 drop table t;
 
+--echo #
+--echo # MDEV-27617 HANDLER KEY > (x) does not work with DESC keys, Spider is affected and returns wrong results
+--echo #
+create table t (a int, b char(1), primary key(a desc)) engine=myisam;
+insert into t VALUES (1,'f'),(2,'g'),(3,'j'), (4,'i'),(5,'h');
+handler t open;
+--echo # MUST return 2,'g'. '>' always means READ_AFTER_KEY. desc or not.
+handler t read `primary` > (3);
+handler t close;
+drop table t;
+
 --echo #
 --echo # End of 10.8 tests
 --echo #

storage/spider/mysql-test/spider/bugfix/r/index.result

@@ -38,6 +38,39 @@ id
 5
 6
 drop table t_sp1, auto_test_local.t;
+#
+# MDEV-27581 Wrong result with DESC key on partitioned Spider table
+#
+create table auto_test_local.t1 (a int primary key);
+create table auto_test_local.t2 (a int primary key);
+create table t (a int, primary key (a desc)) engine=spider
+engine=spider comment='wrapper "mysql", srv "s_1"'
+partition by range (a)
+(partition p1 values less than (4) comment "table 't1'",
+partition p2 values less than (maxvalue) comment "table 't2'");
+insert into t values (1),(2),(10),(11);
+select * from t where a > 1 order by a;
+a
+2
+10
+11
+drop table t, auto_test_local.t1, auto_test_local.t2;
+#
+# MDEV-27617 HANDLER KEY > (x) does not work with DESC keys, Spider is affected and returns wrong results
+#
+create table auto_test_local.t (a int, b char(1), primary key(a desc));
+insert into auto_test_local.t VALUES (1,'f'),(2,'g'),(3,'j'), (4,'i'),(5,'h');
+create table ts (a int, b char(1), primary key(a desc))
+engine=spider comment='wrapper "mysql", srv "s_1", table "t"';
+set spider_use_handler=3;
+select a, b from ts where a > 0 and b = 'g' order by a;
+a	b
+2	g
+set spider_use_handler=default;
+select a, b from ts where a > 0 and b = 'g' order by a;
+a	b
+2	g
+drop table ts, auto_test_local.t;
 drop database auto_test_local;
 for master_1
 connection master_1;

storage/spider/mysql-test/spider/bugfix/t/index.test

@@ -5,7 +5,7 @@ set spider_same_server_link= on;
 --echo #
 --echo # MDEV-27590 Auto-increment on Spider tables with DESC PK does not work properly
 --echo #
- 
+
 select @@spider_auto_increment_mode;
 create or replace table auto_test_local.t (id int primary key) engine=InnoDB;
 create or replace table t_sp1 (id int auto_increment, primary key(id desc))
@@ -15,6 +15,34 @@ insert into t_sp1 () values (),(),();
 select * from t_sp1;
 drop table t_sp1, auto_test_local.t;
 
+--echo #
+--echo # MDEV-27581 Wrong result with DESC key on partitioned Spider table
+--echo #
+create table auto_test_local.t1 (a int primary key);
+create table auto_test_local.t2 (a int primary key);
+create table t (a int, primary key (a desc)) engine=spider
+engine=spider comment='wrapper "mysql", srv "s_1"'
+partition by range (a)
+(partition p1 values less than (4) comment "table 't1'",
+ partition p2 values less than (maxvalue) comment "table 't2'");
+
+insert into t values (1),(2),(10),(11);
+select * from t where a > 1 order by a;
+drop table t, auto_test_local.t1, auto_test_local.t2;
+
+--echo #
+--echo # MDEV-27617 HANDLER KEY > (x) does not work with DESC keys, Spider is affected and returns wrong results
+--echo #
+
+create table auto_test_local.t (a int, b char(1), primary key(a desc));
+insert into auto_test_local.t VALUES (1,'f'),(2,'g'),(3,'j'), (4,'i'),(5,'h');
+create table ts (a int, b char(1), primary key(a desc))
+engine=spider comment='wrapper "mysql", srv "s_1", table "t"';
+set spider_use_handler=3;
+select a, b from ts where a > 0 and b = 'g' order by a;
+set spider_use_handler=default;
+select a, b from ts where a > 0 and b = 'g' order by a;
+drop table ts, auto_test_local.t;
 
 drop database auto_test_local;
 --source ../t/test_deinit.inc