Added HANDLER support for MEMORY tables

Added key and file version numbers to MEMORY tables so that we can detect if someone has changed them between HANDLER calls.


mysql-test/suite/handler/aria.result:
  Fixed result after test changes
mysql-test/suite/handler/handler.inc:
  Changed test to use combined key to ensure rows are returned in a pre-determinated order.
mysql-test/suite/handler/heap.result:
  New result
mysql-test/suite/handler/heap.test:
  Added test for HANDLER + HEAP
mysql-test/suite/handler/innodb.result:
  Fixed result after test changes
mysql-test/suite/handler/myisam.result:
  Fixed result after test changes
sql/sql_handler.cc:
  Fixed wrong parameter to ha_index_next_same()
storage/heap/ha_heap.cc:
  Abort key scan if table has changed.
  Abort table scan if table has been recreated.
storage/heap/ha_heap.h:
  Added support for HANDLER
storage/heap/hp_clear.c:
  Increase version number so that we can notice changes if using HANDLER
storage/heap/hp_delete.c:
  Increase key data version number on key changes.
storage/heap/hp_rfirst.c:
  Remember version of key data
  Give error if using read-first on hash key.
storage/heap/hp_rkey.c:
  Remember version of key data
storage/heap/hp_rlast.c:
  Remember version of key data
  Give error if using read-last on hash key.
storage/heap/hp_rnext.c:
  Fixed that we get next key from last search.
storage/heap/hp_rprev.c:
  Fixed that we get previous key from last search.
storage/heap/hp_scan.c:
  Remember version of key and file data
storage/heap/hp_update.c:
  Increase key data version number on key changes.
storage/heap/hp_write.c:
  Increase key data version number on key changes.

mysql-test/suite/handler/handler.inc

@@ -23,21 +23,21 @@
 # Start testing the table created in init.inc
 #
 handler t1 open as t2;
-handler t2 read a first;
-handler t2 read a next;
-handler t2 read a next;
-handler t2 read a prev;
-handler t2 read a last;
-handler t2 read a prev;
-handler t2 read a prev;
+handler t2 read b first;
+handler t2 read b next;
+handler t2 read b next;
+handler t2 read b prev;
+handler t2 read b last;
+handler t2 read b prev;
+handler t2 read b prev;
 
-handler t2 read a first;
-handler t2 read a prev;
+handler t2 read b first;
+handler t2 read b prev;
 
-handler t2 read a last;
-handler t2 read a prev;
-handler t2 read a next;
-handler t2 read a next;
+handler t2 read b last;
+handler t2 read b prev;
+handler t2 read b next;
+handler t2 read b next;
 
 handler t2 read a=(15);
 handler t2 read a=(16);
@@ -55,16 +55,19 @@ handler t1 read a last;
 handler t2 read a=(11);
 handler t2 read a>=(11);
 
-# Search on something we ca nfind
-handler t2 read a=(18);
-handler t2 read a>=(18);
-handler t2 read a>(18);
-handler t2 read a<=(18);
-handler t2 read a<(18);
+# Search on something we can find
+handler t2 read b=(18);
+handler t2 read b>=(18);
+handler t2 read b>(18);
+handler t2 read b<=(18);
+handler t2 read b<(18);
 
 # Search on something we can't find
+--sorted_result
 handler t2 read a=(15);
+--sorted_result
 handler t2 read a>=(15);
+--sorted_result
 handler t2 read a>(15);
 handler t2 read a<=(15);
 handler t2 read a<(15);
@@ -83,17 +86,17 @@ handler t2 read a>(1);
 handler t2 read a<=(1);
 handler t2 read a<(1);
 
-handler t2 read a first limit 5;
-handler t2 read a next  limit 3;
-handler t2 read a prev  limit 10;
+handler t2 read b first limit 5;
+handler t2 read b next  limit 3;
+handler t2 read b prev  limit 10;
 
 handler t2 read a>=(16) limit 4;
 handler t2 read a>=(16) limit 2,2;
 select * from t1 where a>=16 limit 2,2;
 handler t2 read a last  limit 3;
 handler t2 read a=(16) limit 1,3;
-handler t2 read a=(19);
-handler t2 read a=(19) where b="yyy";
+handler t2 read b=(19);
+handler t2 read b=(19) where b="yyy";
 
 handler t2 read first;
 handler t2 read next;
@@ -450,7 +453,7 @@ drop table t1;
 # is open by a HANDLER, no other statement can access it.
 #
 
-eval create temporary table t1 (a int, b char(1), key a $key_type (a), key b(a,b));
+eval create temporary table t1 (a int, b char(1), key a $key_type (a), key b $key_type (a,b));
 insert into t1 values (0,"a"),(1,"b"),(2,"c"),(3,"d"),(4,"e"),
                       (5,"f"),(6,"g"),(7,"h"),(8,"i"),(9,"j"),(9,'k');
 select a,b from t1;
@@ -466,12 +469,12 @@ handler a1 read a=(6) where b="g";
 handler a1 close;
 select a,b from t1;
 handler t1 open as a2;
-handler a2 read a=(9);
-handler a2 read a next;
-handler a2 read a prev limit 2;
+handler a2 read b=(9);
+handler a2 read b next;
+handler a2 read b prev limit 2;
 --error 0,1031
-handler a2 read a last;
-handler a2 read a prev;
+handler a2 read b last;
+handler a2 read b prev;
 handler a2 close;
 drop table t1;