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.

include/heap.h

@@ -136,6 +136,8 @@ typedef struct st_heap_share
   ulong min_records,max_records;	/* Params to open */
   ulonglong data_length,index_length,max_table_size;
   uint key_stat_version;                /* version to indicate insert/delete */
+  uint key_version;                     /* Updated on key change */
+  uint file_version;                    /* Update on clear */
   uint records;				/* records */
   uint blength;				/* records rounded up to 2^n */
   uint deleted;				/* Deleted records in database */
@@ -173,6 +175,8 @@ typedef struct st_heap_info
   enum ha_rkey_function last_find_flag;
   TREE_ELEMENT *parents[MAX_TREE_HEIGHT+1];
   TREE_ELEMENT **last_pos;
+  uint key_version;                     /* Version at last read */
+  uint file_version;                    /* Version at scan */
   uint lastkey_len;
   my_bool implicit_emptied;
 #ifdef THREAD

mysql-test/suite/handler/aria.result

@@ -6,42 +6,42 @@ insert into t1 values
 (14,"aaa"),(16,"ccc"),(16,"xxx"),
 (20,"ggg"),(21,"hhh"),(22,"iii");
 handler t1 open as t2;
-handler t2 read a first;
+handler t2 read b first;
 a	b
 14	aaa
-handler t2 read a next;
+handler t2 read b next;
 a	b
 16	ccc
-handler t2 read a next;
+handler t2 read b next;
 a	b
 16	xxx
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 16	ccc
-handler t2 read a last;
+handler t2 read b last;
 a	b
 22	iii
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 21	hhh
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 20	ggg
-handler t2 read a first;
+handler t2 read b first;
 a	b
 14	aaa
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
-handler t2 read a last;
+handler t2 read b last;
 a	b
 22	iii
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 21	hhh
-handler t2 read a next;
+handler t2 read b next;
 a	b
 22	iii
-handler t2 read a next;
+handler t2 read b next;
 a	b
 handler t2 read a=(15);
 a	b
@@ -66,19 +66,19 @@ a	b
 handler t2 read a>=(11);
 a	b
 14	aaa
-handler t2 read a=(18);
+handler t2 read b=(18);
 a	b
 18	eee
-handler t2 read a>=(18);
+handler t2 read b>=(18);
 a	b
 18	eee
-handler t2 read a>(18);
+handler t2 read b>(18);
 a	b
 19	fff
-handler t2 read a<=(18);
+handler t2 read b<=(18);
 a	b
 18	eee
-handler t2 read a<(18);
+handler t2 read b<(18);
 a	b
 17	ddd
 handler t2 read a=(15);
@@ -119,19 +119,19 @@ handler t2 read a<=(1);
 a	b
 handler t2 read a<(1);
 a	b
-handler t2 read a first limit 5;
+handler t2 read b first limit 5;
 a	b
 14	aaa
 16	ccc
 16	xxx
 17	ddd
 18	eee
-handler t2 read a next  limit 3;
+handler t2 read b next  limit 3;
 a	b
 19	fff
 19	yyy
 20	ggg
-handler t2 read a prev  limit 10;
+handler t2 read b prev  limit 10;
 a	b
 19	yyy
 19	fff
@@ -162,10 +162,10 @@ a	b
 handler t2 read a=(16) limit 1,3;
 a	b
 16	xxx
-handler t2 read a=(19);
+handler t2 read b=(19);
 a	b
 19	fff
-handler t2 read a=(19) where b="yyy";
+handler t2 read b=(19) where b="yyy";
 a	b
 19	yyy
 handler t2 read first;
@@ -557,7 +557,7 @@ handler t1_alias READ a next where inexistent > 0;
 ERROR 42S22: Unknown column 'inexistent' in 'field list'
 handler t1_alias close;
 drop table t1;
-create temporary table t1 (a int, b char(1), key a  (a), key b(a,b));
+create temporary table t1 (a int, b char(1), key a  (a), key b  (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;
@@ -609,20 +609,20 @@ a	b
 9	j
 9	k
 handler t1 open as a2;
-handler a2 read a=(9);
+handler a2 read b=(9);
 a	b
 9	j
-handler a2 read a next;
+handler a2 read b next;
 a	b
 9	k
-handler a2 read a prev limit 2;
+handler a2 read b prev limit 2;
 a	b
 9	j
 8	i
-handler a2 read a last;
+handler a2 read b last;
 a	b
 9	k
-handler a2 read a prev;
+handler a2 read b prev;
 a	b
 9	j
 handler a2 close;

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 a first;
-handler t2 read a 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 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 b first;
+handler t2 read b prev;
+
+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;
 

mysql-test/suite/handler/heap.result

+SET SESSION STORAGE_ENGINE = MEMORY;
+drop table if exists t1,t3,t4,t5;
+create table t1 (a int, b char(10), key a using btree (a), key b using btree (a,b));
+insert into t1 values
+(17,"ddd"),(18,"eee"),(19,"fff"),(19,"yyy"),
+(14,"aaa"),(16,"ccc"),(16,"xxx"),
+(20,"ggg"),(21,"hhh"),(22,"iii");
+handler t1 open as t2;
+handler t2 read b first;
+a	b
+14	aaa
+handler t2 read b next;
+a	b
+16	ccc
+handler t2 read b next;
+a	b
+16	xxx
+handler t2 read b prev;
+a	b
+16	ccc
+handler t2 read b last;
+a	b
+22	iii
+handler t2 read b prev;
+a	b
+21	hhh
+handler t2 read b prev;
+a	b
+20	ggg
+handler t2 read b first;
+a	b
+14	aaa
+handler t2 read b prev;
+a	b
+handler t2 read b last;
+a	b
+22	iii
+handler t2 read b prev;
+a	b
+21	hhh
+handler t2 read b next;
+a	b
+22	iii
+handler t2 read b next;
+a	b
+handler t2 read a=(15);
+a	b
+handler t2 read a=(16);
+a	b
+16	ccc
+handler t2 read a=(19,"fff");
+ERROR 42000: Too many key parts specified; max 1 parts allowed
+handler t2 read b=(19,"fff");
+a	b
+19	fff
+handler t2 read b=(19,"yyy");
+a	b
+19	yyy
+handler t2 read b=(19);
+a	b
+19	fff
+handler t1 read a last;
+ERROR 42S02: Unknown table 't1' in HANDLER
+handler t2 read a=(11);
+a	b
+handler t2 read a>=(11);
+a	b
+14	aaa
+handler t2 read b=(18);
+a	b
+18	eee
+handler t2 read b>=(18);
+a	b
+18	eee
+handler t2 read b>(18);
+a	b
+19	fff
+handler t2 read b<=(18);
+a	b
+18	eee
+handler t2 read b<(18);
+a	b
+17	ddd
+handler t2 read a=(15);
+a	b
+handler t2 read a>=(15);
+a	b
+16	ccc
+handler t2 read a>(15);
+a	b
+16	ccc
+handler t2 read a<=(15);
+a	b
+14	aaa
+handler t2 read a<(15);
+a	b
+14	aaa
+handler t2 read a=(54);
+a	b
+handler t2 read a>=(54);
+a	b
+handler t2 read a>(54);
+a	b
+handler t2 read a<=(54);
+a	b
+22	iii
+handler t2 read a<(54);
+a	b
+22	iii
+handler t2 read a=(1);
+a	b
+handler t2 read a>=(1);
+a	b
+14	aaa
+handler t2 read a>(1);
+a	b
+14	aaa
+handler t2 read a<=(1);
+a	b
+handler t2 read a<(1);
+a	b
+handler t2 read b first limit 5;
+a	b
+14	aaa
+16	ccc
+16	xxx
+17	ddd
+18	eee
+handler t2 read b next  limit 3;
+a	b
+19	fff
+19	yyy
+20	ggg
+handler t2 read b prev  limit 10;
+a	b
+19	yyy
+19	fff
+18	eee
+17	ddd
+16	xxx
+16	ccc
+14	aaa
+handler t2 read a>=(16) limit 4;
+a	b
+16	ccc
+16	xxx
+17	ddd
+18	eee
+handler t2 read a>=(16) limit 2,2;
+a	b
+17	ddd
+18	eee
+select * from t1 where a>=16 limit 2,2;
+a	b
+17	ddd
+18	eee
+handler t2 read a last  limit 3;
+a	b
+22	iii
+21	hhh
+20	ggg
+handler t2 read a=(16) limit 1,3;
+a	b
+16	xxx
+handler t2 read b=(19);
+a	b
+19	fff
+handler t2 read b=(19) where b="yyy";
+a	b
+19	yyy
+handler t2 read first;
+a	b
+17	ddd
+handler t2 read next;
+a	b
+18	eee
+handler t2 read next;
+a	b
+19	fff
+handler t2 close;
+handler t1 open;
+handler t1 read a next;
+a	b
+14	aaa
+handler t1 read a next;
+a	b
+16	ccc
+handler t1 close;
+handler t1 open;
+handler t1 read a prev;
+a	b
+22	iii
+handler t1 read a prev;
+a	b
+21	hhh
+handler t1 close;
+handler t1 open as t2;
+handler t2 read first;
+a	b
+17	ddd
+alter table t1 engine = MEMORY;
+handler t2 read first;
+ERROR 42S02: Unknown table 't2' in HANDLER
+handler t1 open;
+handler t1 read a=(16) limit 1,3;
+a	b
+16	xxx
+flush tables;
+handler t1 read a=(16) limit 1,3;
+a	b
+16	xxx
+handler t1 close;
+handler t1 open;
+prepare stmt from 'handler t1 read a=(?) limit ?,?';
+set @a=16,@b=1,@c=100;
+execute stmt using @a,@b,@c;
+a	b
+16	xxx
+set @a=16,@b=2,@c=1;
+execute stmt using @a,@b,@c;
+a	b
+set @a=16,@b=0,@c=2;
+execute stmt using @a,@b,@c;
+a	b
+16	ccc
+16	xxx
+deallocate prepare stmt;
+prepare stmt from 'handler t1 read a next limit ?';
+handler t1 read a>=(11);
+a	b
+14	aaa
+set @a=3;
+execute stmt using @a;
+a	b
+16	ccc
+16	xxx
+17	ddd
+execute stmt using @a;
+a	b
+18	eee
+19	fff
+19	yyy
+execute stmt using @a;
+a	b
+20	ggg
+21	hhh
+22	iii
+deallocate prepare stmt;
+prepare stmt from 'handler t1 read b prev limit ?';
+execute stmt using @a;
+a	b
+22	iii
+21	hhh
+20	ggg
+execute stmt using @a;
+a	b
+19	yyy
+19	fff
+18	eee
+execute stmt using @a;
+a	b
+17	ddd
+16	xxx
+16	ccc
+execute stmt using @a;
+a	b
+14	aaa
+deallocate prepare stmt;
+prepare stmt from 'handler t1 read b=(?,?)';
+set @a=14, @b='aaa';
+execute stmt using @a,@b;
+a	b
+14	aaa
+set @a=14, @b='not found';
+execute stmt using @a,@b;
+a	b
+deallocate prepare stmt;
+prepare stmt from 'handler t1 read b=(1+?) limit 10';
+set @a=15;
+execute stmt using @a;
+a	b
+16	ccc
+16	xxx
+execute stmt using @a;
+a	b
+16	ccc
+16	xxx
+deallocate prepare stmt;
+prepare stmt from 'handler t1 read a>=(?) where a < ? limit 5';
+set @a=15, @b=20;
+execute stmt using @a,@b;
+a	b
+16	ccc
+16	xxx
+17	ddd
+18	eee
+19	fff
+execute stmt using @a,@b;
+a	b
+16	ccc
+16	xxx
+17	ddd
+18	eee
+19	fff
+deallocate prepare stmt;
+prepare stmt from 'handler t1 read a=(?)';
+set @a=16;
+execute stmt using @a;
+a	b
+16	ccc
+alter table t1 add c int;
+execute stmt using @a;
+ERROR 42S02: Unknown table 't1' in HANDLER
+deallocate prepare stmt;
+handler t1 close;
+ERROR 42S02: Unknown table 't1' in HANDLER
+handler t1 open;
+prepare stmt from 'handler t1 read a=(?)';
+flush tables;
+set @a=16;
+execute stmt using @a;
+ERROR HY000: Prepared statement needs to be re-prepared
+deallocate prepare stmt;
+handler t1 close;
+handler t1 open as t2;
+drop table t1;
+create table t1 (a int not null);
+insert into t1 values (17);
+handler t2 read first;
+ERROR 42S02: Unknown table 't2' in HANDLER
+handler t1 open as t2;
+alter table t1 engine=CSV;
+handler t2 read first;
+ERROR 42S02: Unknown table 't2' in HANDLER
+drop table t1;
+create table t1 (a int);
+insert into t1 values (1),(2),(3),(4),(5),(6);
+delete from t1 limit 2;
+handler t1 open;
+handler t1 read first;
+a
+3
+handler t1 read first limit 1,1;
+a
+4
+handler t1 read first limit 2,2;
+a
+5
+6
+delete from t1 limit 3;
+handler t1 read first;
+a
+6
+drop table t1;
+create table t1(a int, index using btree (a));
+insert into t1 values (1), (2), (3);
+handler t1 open;
+handler t1 read a=(W);
+ERROR 42S22: Unknown column 'W' in 'field list'
+handler t1 read a=(a);
+ERROR HY000: Incorrect arguments to HANDLER ... READ
+drop table t1;
+create table t1 (a char(5));
+insert into t1 values ("Ok");
+handler t1 open as t;
+handler t read first;
+a
+Ok
+use mysql;
+handler t read first;
+a
+Ok
+handler t close;
+handler test.t1 open as t;
+handler t read first;
+a
+Ok
+handler t close;
+use test;
+drop table t1;
+create table t1 ( a int, b int, INDEX a using btree (a) );
+insert into t1 values (1,2), (2,1);
+handler t1 open;
+handler t1 read a=(1) where b=2;
+a	b
+1	2
+handler t1 read a=(1) where b=3;
+a	b
+handler t1 read a=(1) where b=1;
+a	b
+handler t1 close;
+drop table t1;
+create table t1 (c1 char(20));
+insert into t1 values ("t1");
+handler t1 open as h1;
+handler h1 read first limit 9;
+c1
+t1
+create table t2 (c1 char(20));
+insert into t2 values ("t2");
+handler t2 open as h2;
+handler h2 read first limit 9;
+c1
+t2
+create table t3 (c1 char(20));
+insert into t3 values ("t3");
+handler t3 open as h3;
+handler h3 read first limit 9;
+c1
+t3
+create table t4 (c1 char(20));
+insert into t4 values ("t4");
+handler t4 open as h4;
+handler h4 read first limit 9;
+c1
+t4
+create table t5 (c1 char(20));
+insert into t5 values ("t5");
+handler t5 open as h5;
+handler h5 read first limit 9;
+c1
+t5
+alter table t1 engine=MyISAM;
+handler h1 read first limit 9;
+ERROR 42S02: Unknown table 'h1' in HANDLER
+handler h2 read first limit 9;
+c1
+t2
+handler h3 read first limit 9;
+c1
+t3
+handler h4 read first limit 9;
+c1
+t4
+handler h5 read first limit 9;
+c1
+t5
+alter table t5 engine=MyISAM;
+handler h1 read first limit 9;
+ERROR 42S02: Unknown table 'h1' in HANDLER
+handler h2 read first limit 9;
+c1
+t2
+handler h3 read first limit 9;
+c1
+t3
+handler h4 read first limit 9;
+c1
+t4
+handler h5 read first limit 9;
+ERROR 42S02: Unknown table 'h5' in HANDLER
+alter table t3 engine=MyISAM;
+handler h1 read first limit 9;
+ERROR 42S02: Unknown table 'h1' in HANDLER
+handler h2 read first limit 9;
+c1
+t2
+handler h3 read first limit 9;
+ERROR 42S02: Unknown table 'h3' in HANDLER
+handler h4 read first limit 9;
+c1
+t4
+handler h5 read first limit 9;
+ERROR 42S02: Unknown table 'h5' in HANDLER
+handler h2 close;
+handler h4 close;
+handler t1 open as h1_1;
+handler t1 open as h1_2;
+handler t1 open as h1_3;
+handler h1_1 read first limit 9;
+c1
+t1
+handler h1_2 read first limit 9;
+c1
+t1
+handler h1_3 read first limit 9;
+c1
+t1
+alter table t1 engine=MEMORY;
+handler h1_1 read first limit 9;
+ERROR 42S02: Unknown table 'h1_1' in HANDLER
+handler h1_2 read first limit 9;
+ERROR 42S02: Unknown table 'h1_2' in HANDLER
+handler h1_3 read first limit 9;
+ERROR 42S02: Unknown table 'h1_3' in HANDLER
+drop table t1;
+drop table t2;
+drop table t3;
+drop table t4;
+drop table t5;
+create table t1 (c1 int);
+insert into t1 values (1);
+handler t1 open;
+handler t1 read first;
+c1
+1
+send the below to another connection, do not wait for the result
+optimize table t1;
+proceed with the normal connection
+handler t1 read next;
+c1
+1
+handler t1 close;
+read the result from the other connection
+Table	Op	Msg_type	Msg_text
+test.t1	optimize	note	The storage engine for the table doesn't support optimize
+proceed with the normal connection
+drop table t1;
+CREATE TABLE t1 (  no1 smallint(5) NOT NULL default '0',  no2 int(10) NOT NULL default '0',  PRIMARY KEY using btree (no1,no2));
+INSERT INTO t1 VALUES (1,274),(1,275),(2,6),(2,8),(4,1),(4,2);
+HANDLER t1 OPEN;
+HANDLER t1 READ `primary` = (1, 1000);
+no1	no2
+HANDLER t1 READ `primary` PREV;
+no1	no2
+1	275
+HANDLER t1 READ `primary` = (1, 1000);
+no1	no2
+HANDLER t1 READ `primary` NEXT;
+no1	no2
+2	6
+DROP TABLE t1;
+create table t1 (c1 int);
+insert into t1 values (14397);
+flush tables with read lock;
+drop table t1;
+ERROR HY000: Can't execute the query because you have a conflicting read lock
+send the below to another connection, do not wait for the result
+drop table t1;
+proceed with the normal connection
+select * from t1;
+c1
+14397
+unlock tables;
+read the result from the other connection
+proceed with the normal connection
+select * from t1;
+ERROR 42S02: Table 'test.t1' doesn't exist
+drop table if exists t1;
+Warnings:
+Note	1051	Unknown table 't1'
+create table t1 (a int not null) ENGINE=CSV;
+--> client 2
+handler t1 open;
+ERROR HY000: Table storage engine for 't1' doesn't have this option
+--> client 1
+drop table t1;
+create table t1 (a int);
+handler t1 open as t1_alias;
+handler t1_alias read a next;
+ERROR 42000: Key 'a' doesn't exist in table 't1_alias'
+handler t1_alias READ a next where inexistent > 0;
+ERROR 42S22: Unknown column 'inexistent' in 'field list'
+handler t1_alias read a next;
+ERROR 42000: Key 'a' doesn't exist in table 't1_alias'
+handler t1_alias READ a next where inexistent > 0;
+ERROR 42S22: Unknown column 'inexistent' in 'field list'
+handler t1_alias close;
+drop table t1;
+create temporary table t1 (a int, b char(1), key a using btree (a), key b using btree (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;
+a	b
+0	a
+1	b
+2	c
+3	d
+4	e
+5	f
+6	g
+7	h
+8	i
+9	j
+9	k
+handler t1 open as a1;
+handler a1 read a=(1);
+a	b
+1	b
+handler a1 read a next;
+a	b
+2	c
+handler a1 read a next;
+a	b
+3	d
+select a,b from t1;
+ERROR HY000: Can't reopen table: 'a1'
+handler a1 read a prev;
+a	b
+2	c
+handler a1 read a prev;
+a	b
+1	b
+handler a1 read a=(6) where b="g";
+a	b
+6	g
+handler a1 close;
+select a,b from t1;
+a	b
+0	a
+1	b
+2	c
+3	d
+4	e
+5	f
+6	g
+7	h
+8	i
+9	j
+9	k
+handler t1 open as a2;
+handler a2 read b=(9);
+a	b
+9	j
+handler a2 read b next;
+a	b
+9	k
+handler a2 read b prev limit 2;
+a	b
+9	j
+8	i
+handler a2 read b last;
+a	b
+9	k
+handler a2 read b prev;
+a	b
+9	j
+handler a2 close;
+drop table t1;
+create table t1 (a int);
+create temporary table t2 (a int, key using btree (a));
+handler t1 open as a1;
+handler t2 open as a2;
+handler a2 read a first;
+a
+drop table t1, t2;
+handler a2 read a next;
+ERROR 42S02: Unknown table 'a2' in HANDLER
+handler a1 close;
+ERROR 42S02: Unknown table 'a1' in HANDLER
+create table t1 (a int, key using btree (a));
+create table t2 like t1;
+handler t1 open as a1;
+handler t2 open as a2;
+handler a1 read a first;
+a
+handler a2 read a first;
+a
+alter table t1 add b int;
+handler a1 close;
+ERROR 42S02: Unknown table 'a1' in HANDLER
+handler a2 close;
+drop table t1, t2;
+create table t1 (a int, key using btree (a));
+handler t1 open as a1;
+handler a1 read a first;
+a
+rename table t1 to t2;
+handler a1 read a first;
+ERROR 42S02: Unknown table 'a1' in HANDLER
+drop table t2;
+create table t1 (a int, key using btree (a));
+create table t2 like t1;
+handler t1 open as a1;
+handler t2 open as a2;
+handler a1 read a first;
+a
+handler a2 read a first;
+a
+optimize table t1;
+Table	Op	Msg_type	Msg_text
+test.t1	optimize	note	The storage engine for the table doesn't support optimize
+handler a1 close;
+ERROR 42S02: Unknown table 'a1' in HANDLER
+handler a2 close;
+drop table t1, t2;
+#
+# BUG#51877 - HANDLER interface causes invalid memory read
+#
+CREATE TABLE t1(a INT, KEY using btree (a));
+HANDLER t1 OPEN;
+HANDLER t1 READ a FIRST;
+a
+INSERT INTO t1 VALUES(1);
+HANDLER t1 READ a NEXT;
+HANDLER t1 CLOSE;
+DROP TABLE t1;
+CREATE TABLE t1(a INT, b INT, KEY(a), KEY b using btree (b), KEY ab using btree(a, b));
+INSERT INTO t1 VALUES (2, 20), (2,20), (1, 10), (4, 40), (3, 30), (5,50), (6,50);
+HANDLER t1 OPEN;
+HANDLER t1 READ a>=(2) limit 3;
+a	b
+2	20
+2	20
+HANDLER t1 READ a PREV;
+a	b
+2	20
+HANDLER t1 READ a PREV;
+a	b
+2	20
+HANDLER t1 READ a PREV;
+a	b
+HANDLER t1 READ b>=(20) limit 3;
+a	b
+2	20
+2	20
+3	30
+HANDLER t1 READ b PREV;
+a	b
+2	20
+HANDLER t1 READ b PREV LIMIT 2;
+a	b
+2	20
+1	10
+HANDLER t1 READ ab=(3,30) limit 3;
+a	b
+3	30
+HANDLER t1 READ ab>=(3,30) limit 3;
+a	b
+3	30
+4	40
+5	50
+HANDLER t1 READ a FIRST;
+ERROR HY000: Table storage engine for 't1' doesn't have this option
+HANDLER t1 READ a LAST;
+ERROR HY000: Table storage engine for 't1' doesn't have this option
+HANDLER t1 READ b FIRST LIMIT 2;
+a	b
+1	10
+2	20
+HANDLER t1 READ b LAST LIMIT 2;
+a	b
+6	50
+5	50
+HANDLER t1 READ FIRST LIMIT 10;
+a	b
+2	20
+2	20
+1	10
+4	40
+3	30
+5	50
+6	50
+HANDLER t1 READ b FIRST;
+a	b
+1	10
+insert into t1 values (7,50);
+HANDLER t1 READ b NEXT;
+ERROR HY000: Record has changed since last read in table 't1'
+HANDLER t1 READ b FIRST;
+a	b
+1	10
+insert into t1 values (7,50);
+HANDLER t1 READ b NEXT;
+ERROR HY000: Record has changed since last read in table 't1'
+HANDLER t1 READ FIRST;
+a	b
+2	20
+insert into t1 values (8,50);
+HANDLER t1 READ NEXT;
+a	b
+2	20
+delete from t1 where a=3;
+HANDLER t1 READ NEXT LIMIT 2;
+a	b
+1	10
+4	40
+delete from t1;
+HANDLER t1 READ NEXT LIMIT 2;
+ERROR HY000: Record has changed since last read in table 't1'
+HANDLER t1 CLOSE;
+DROP TABLE t1;
+End of 5.1 tests

mysql-test/suite/handler/heap.test

+# test of HANDLER with HEAP tables
+#
+
+let $engine_type= MEMORY;
+let $key_type=using btree;
+
+--source init.inc
+--source handler.inc
+
+#
+# Test what happens if table is changed (Unique test for HEAP)
+#
+
+connect (con1,localhost,root,,);
+connection default;
+
+CREATE TABLE t1(a INT, b INT, KEY(a), KEY b using btree (b), KEY ab using btree(a, b));
+
+INSERT INTO t1 VALUES (2, 20), (2,20), (1, 10), (4, 40), (3, 30), (5,50), (6,50);
+
+HANDLER t1 OPEN;
+HANDLER t1 READ a>=(2) limit 3;
+HANDLER t1 READ a PREV;
+HANDLER t1 READ a PREV;
+HANDLER t1 READ a PREV;
+HANDLER t1 READ b>=(20) limit 3;
+HANDLER t1 READ b PREV;
+HANDLER t1 READ b PREV LIMIT 2;
+HANDLER t1 READ ab=(3,30) limit 3;
+HANDLER t1 READ ab>=(3,30) limit 3;
+
+# Test FIRST/LAST on hash and btree keys
+--error ER_ILLEGAL_HA
+HANDLER t1 READ a FIRST;
+--error ER_ILLEGAL_HA
+HANDLER t1 READ a LAST;
+HANDLER t1 READ b FIRST LIMIT 2;
+HANDLER t1 READ b LAST LIMIT 2; 
+
+# Table scan
+HANDLER t1 READ FIRST LIMIT 10;
+# Index scan
+HANDLER t1 READ b FIRST;
+insert into t1 values (7,50);
+--error ER_CHECKREAD
+HANDLER t1 READ b NEXT;
+
+HANDLER t1 READ b FIRST;
+connection con1;
+insert into t1 values (7,50);
+connection default;
+--error ER_CHECKREAD
+HANDLER t1 READ b NEXT;
+
+HANDLER t1 READ FIRST;
+connection con1;
+insert into t1 values (8,50);
+connection default;
+HANDLER t1 READ NEXT;
+connection con1;
+delete from t1 where a=3;
+connection default;
+HANDLER t1 READ NEXT LIMIT 2;
+connection con1;
+delete from t1;
+connection default;
+--error ER_CHECKREAD
+HANDLER t1 READ NEXT LIMIT 2;
+HANDLER t1 CLOSE;
+DROP TABLE t1;
+disconnect con1;
+
+--echo End of 5.1 tests

mysql-test/suite/handler/innodb.result

@@ -6,42 +6,42 @@ insert into t1 values
 (14,"aaa"),(16,"ccc"),(16,"xxx"),
 (20,"ggg"),(21,"hhh"),(22,"iii");
 handler t1 open as t2;
-handler t2 read a first;
+handler t2 read b first;
 a	b
 14	aaa
-handler t2 read a next;
+handler t2 read b next;
 a	b
 16	ccc
-handler t2 read a next;
+handler t2 read b next;
 a	b
 16	xxx
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 16	ccc
-handler t2 read a last;
+handler t2 read b last;
 a	b
 22	iii
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 21	hhh
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 20	ggg
-handler t2 read a first;
+handler t2 read b first;
 a	b
 14	aaa
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
-handler t2 read a last;
+handler t2 read b last;
 a	b
 22	iii
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 21	hhh
-handler t2 read a next;
+handler t2 read b next;
 a	b
 22	iii
-handler t2 read a next;
+handler t2 read b next;
 a	b
 handler t2 read a=(15);
 a	b
@@ -66,19 +66,19 @@ a	b
 handler t2 read a>=(11);
 a	b
 14	aaa
-handler t2 read a=(18);
+handler t2 read b=(18);
 a	b
 18	eee
-handler t2 read a>=(18);
+handler t2 read b>=(18);
 a	b
 18	eee
-handler t2 read a>(18);
+handler t2 read b>(18);
 a	b
 19	fff
-handler t2 read a<=(18);
+handler t2 read b<=(18);
 a	b
 18	eee
-handler t2 read a<(18);
+handler t2 read b<(18);
 a	b
 17	ddd
 handler t2 read a=(15);
@@ -119,19 +119,19 @@ handler t2 read a<=(1);
 a	b
 handler t2 read a<(1);
 a	b
-handler t2 read a first limit 5;
+handler t2 read b first limit 5;
 a	b
 14	aaa
 16	ccc
 16	xxx
 17	ddd
 18	eee
-handler t2 read a next  limit 3;
+handler t2 read b next  limit 3;
 a	b
 19	fff
 19	yyy
 20	ggg
-handler t2 read a prev  limit 10;
+handler t2 read b prev  limit 10;
 a	b
 19	yyy
 19	fff
@@ -162,10 +162,10 @@ a	b
 handler t2 read a=(16) limit 1,3;
 a	b
 16	xxx
-handler t2 read a=(19);
+handler t2 read b=(19);
 a	b
 19	fff
-handler t2 read a=(19) where b="yyy";
+handler t2 read b=(19) where b="yyy";
 a	b
 19	yyy
 handler t2 read first;
@@ -558,7 +558,7 @@ handler t1_alias READ a next where inexistent > 0;
 ERROR 42S22: Unknown column 'inexistent' in 'field list'
 handler t1_alias close;
 drop table t1;
-create temporary table t1 (a int, b char(1), key a  (a), key b(a,b));
+create temporary table t1 (a int, b char(1), key a  (a), key b  (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;
@@ -610,20 +610,20 @@ a	b
 9	j
 9	k
 handler t1 open as a2;
-handler a2 read a=(9);
+handler a2 read b=(9);
 a	b
 9	j
-handler a2 read a next;
+handler a2 read b next;
 a	b
 9	k
-handler a2 read a prev limit 2;
+handler a2 read b prev limit 2;
 a	b
 9	j
 8	i
-handler a2 read a last;
+handler a2 read b last;
 a	b
 9	k
-handler a2 read a prev;
+handler a2 read b prev;
 a	b
 9	j
 handler a2 close;

mysql-test/suite/handler/myisam.result

@@ -6,42 +6,42 @@ insert into t1 values
 (14,"aaa"),(16,"ccc"),(16,"xxx"),
 (20,"ggg"),(21,"hhh"),(22,"iii");
 handler t1 open as t2;
-handler t2 read a first;
+handler t2 read b first;
 a	b
 14	aaa
-handler t2 read a next;
+handler t2 read b next;
 a	b
 16	ccc
-handler t2 read a next;
+handler t2 read b next;
 a	b
 16	xxx
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 16	ccc
-handler t2 read a last;
+handler t2 read b last;
 a	b
 22	iii
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 21	hhh
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 20	ggg
-handler t2 read a first;
+handler t2 read b first;
 a	b
 14	aaa
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
-handler t2 read a last;
+handler t2 read b last;
 a	b
 22	iii
-handler t2 read a prev;
+handler t2 read b prev;
 a	b
 21	hhh
-handler t2 read a next;
+handler t2 read b next;
 a	b
 22	iii
-handler t2 read a next;
+handler t2 read b next;
 a	b
 handler t2 read a=(15);
 a	b
@@ -66,19 +66,19 @@ a	b
 handler t2 read a>=(11);
 a	b
 14	aaa
-handler t2 read a=(18);
+handler t2 read b=(18);
 a	b
 18	eee
-handler t2 read a>=(18);
+handler t2 read b>=(18);
 a	b
 18	eee
-handler t2 read a>(18);
+handler t2 read b>(18);
 a	b
 19	fff
-handler t2 read a<=(18);
+handler t2 read b<=(18);
 a	b
 18	eee
-handler t2 read a<(18);
+handler t2 read b<(18);
 a	b
 17	ddd
 handler t2 read a=(15);
@@ -119,19 +119,19 @@ handler t2 read a<=(1);
 a	b
 handler t2 read a<(1);
 a	b
-handler t2 read a first limit 5;
+handler t2 read b first limit 5;
 a	b
 14	aaa
 16	ccc
 16	xxx
 17	ddd
 18	eee
-handler t2 read a next  limit 3;
+handler t2 read b next  limit 3;
 a	b
 19	fff
 19	yyy
 20	ggg
-handler t2 read a prev  limit 10;
+handler t2 read b prev  limit 10;
 a	b
 19	yyy
 19	fff
@@ -162,10 +162,10 @@ a	b
 handler t2 read a=(16) limit 1,3;
 a	b
 16	xxx
-handler t2 read a=(19);
+handler t2 read b=(19);
 a	b
 19	fff
-handler t2 read a=(19) where b="yyy";
+handler t2 read b=(19) where b="yyy";
 a	b
 19	yyy
 handler t2 read first;
@@ -557,7 +557,7 @@ handler t1_alias READ a next where inexistent > 0;
 ERROR 42S22: Unknown column 'inexistent' in 'field list'
 handler t1_alias close;
 drop table t1;
-create temporary table t1 (a int, b char(1), key a  (a), key b(a,b));
+create temporary table t1 (a int, b char(1), key a  (a), key b  (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;
@@ -609,20 +609,20 @@ a	b
 9	j
 9	k
 handler t1 open as a2;
-handler a2 read a=(9);
+handler a2 read b=(9);
 a	b
 9	j
-handler a2 read a next;
+handler a2 read b next;
 a	b
 9	k
-handler a2 read a prev limit 2;
+handler a2 read b prev limit 2;
 a	b
 9	j
 8	i
-handler a2 read a last;
+handler a2 read b last;
 a	b
 9	k
-handler a2 read a prev;
+handler a2 read b prev;
 a	b
 9	j
 handler a2 close;

sql/sql_handler.cc

@@ -657,7 +657,6 @@ bool mysql_ha_read(THD *thd, TABLE_LIST *tables,
   int           error, keyno;
   uint          num_rows;
   uchar		*UNINIT_VAR(key);
-  uint		UNINIT_VAR(key_len);
   bool          need_reopen;
   List_iterator<Item> it;
   DBUG_ENTER("mysql_ha_read");
@@ -784,7 +783,8 @@ retry:
     case RNEXT_SAME:
       /* Continue scan on "(keypart1,keypart2,...)=(c1, c2, ...)  */
       DBUG_ASSERT(keyname != 0);
-      error= table->file->ha_index_next_same(table->record[0], key, key_len);
+      error= table->file->ha_index_next_same(table->record[0], key,
+                                             handler->key_len);
       break;
     case RKEY:
     {

storage/heap/ha_heap.cc

@@ -183,6 +183,19 @@ void ha_heap::set_keys_for_scanning(void)
 }
 
 
+int ha_heap::can_continue_handler_scan()
+{
+  int error= 0;
+  if ((file->key_version != file->s->key_version && inited == INDEX) ||
+      (file->file_version != file->s->file_version && inited == RND))
+  {
+    /* Data changed, not safe to do index or rnd scan */
+    error= HA_ERR_RECORD_CHANGED;
+  }
+  return error;
+}
+
+
 void ha_heap::update_key_stats()
 {
   for (uint i= 0; i < table->s->keys; i++)

storage/heap/ha_heap.h

-/* Copyright (C) 2000-2006 MySQL AB
+/* Copyright (C) 2000-2006 MySQL AB, 2009-2011 Monty Program Ab
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -52,6 +52,7 @@ public:
   {
     return (HA_FAST_KEY_READ | HA_NO_BLOBS | HA_NULL_IN_KEY |
             HA_BINLOG_ROW_CAPABLE | HA_BINLOG_STMT_CAPABLE |
+            HA_CAN_SQL_HANDLER |
             HA_REC_NOT_IN_SEQ | HA_CAN_INSERT_DELAYED | HA_NO_TRANSACTIONS |
             HA_HAS_RECORDS | HA_STATS_RECORDS_IS_EXACT);
   }
@@ -93,6 +94,7 @@ public:
   int rnd_next(uchar *buf);
   int rnd_pos(uchar * buf, uchar *pos);
   void position(const uchar *record);
+  int can_continue_handler_scan();
   int info(uint);
   int extra(enum ha_extra_function operation);
   int reset();

storage/heap/hp_clear.c

@@ -40,6 +40,8 @@ void hp_clear(HP_SHARE *info)
   info->blength=1;
   info->changed=0;
   info->del_link=0;
+  info->key_version++;
+  info->file_version++;
   DBUG_VOID_RETURN;
 }
 

storage/heap/hp_delete.c

@@ -47,6 +47,7 @@ int heap_delete(HP_INFO *info, const uchar *record)
   share->del_link=pos;
   pos[share->reclength]=0;		/* Record deleted */
   share->deleted++;
+  share->key_version++;
   info->current_hash_ptr=0;
 #if !defined(DBUG_OFF) && defined(EXTRA_HEAP_DEBUG)
   DBUG_EXECUTE("check_heap",heap_check_heap(info, 0););

storage/heap/hp_rfirst.c

@@ -24,6 +24,8 @@ int heap_rfirst(HP_INFO *info, uchar *record, int inx)
   
   DBUG_ENTER("heap_rfirst");
   info->lastinx= inx;
+  info->key_version= info->s->key_version;
+
   if (keyinfo->algorithm == HA_KEY_ALG_BTREE)
   {
     uchar *pos;
@@ -57,15 +59,8 @@ int heap_rfirst(HP_INFO *info, uchar *record, int inx)
   }
   else
   {
-    if (!(info->s->records))
-    {
-      my_errno=HA_ERR_END_OF_FILE;
+    /* We can't scan a non existing key value with hash index */
+    my_errno= HA_ERR_WRONG_COMMAND;
     DBUG_RETURN(my_errno);
   }
-    DBUG_ASSERT(0); /* TODO fix it */
-    info->current_record=0;
-    info->current_hash_ptr=0;
-    info->update=HA_STATE_PREV_FOUND;
-    DBUG_RETURN(heap_rnext(info,record));
-  }
 }

storage/heap/hp_rkey.c

@@ -30,6 +30,7 @@ int heap_rkey(HP_INFO *info, uchar *record, int inx, const uchar *key,
   }
   info->lastinx= inx;
   info->current_record= (ulong) ~0L;		/* For heap_rrnd() */
+  info->key_version= info->s->key_version;
 
   if (keyinfo->algorithm == HA_KEY_ALG_BTREE)
   {

storage/heap/hp_rlast.c

@@ -25,6 +25,7 @@ int heap_rlast(HP_INFO *info, uchar *record, int inx)
 
   DBUG_ENTER("heap_rlast");
   info->lastinx= inx;
+  info->key_version= info->s->key_version;
   if (keyinfo->algorithm == HA_KEY_ALG_BTREE)
   {
     uchar *pos;
@@ -47,9 +48,8 @@ int heap_rlast(HP_INFO *info, uchar *record, int inx)
   }
   else
   {
-    info->current_ptr=0;
-    info->current_hash_ptr=0;
-    info->update=HA_STATE_NEXT_FOUND;
-    DBUG_RETURN(heap_rprev(info,record));
+    /* We can't scan a non existing key value with hash index */
+    my_errno= HA_ERR_WRONG_COMMAND;
+    DBUG_RETURN(my_errno);
   }
 }

storage/heap/hp_rnext.c

@@ -70,6 +70,7 @@ int heap_rnext(HP_INFO *info, uchar *record)
       custom_arg.keyseg = keyinfo->seg;
       custom_arg.key_length = info->lastkey_len;
       custom_arg.search_flag = SEARCH_SAME | SEARCH_FIND;
+      info->last_find_flag= HA_READ_KEY_OR_NEXT;
       pos = tree_search_key(&keyinfo->rb_tree, info->lastkey, info->parents, 
                            &info->last_pos, info->last_find_flag, &custom_arg);
     }

storage/heap/hp_rprev.c

@@ -41,6 +41,7 @@ int heap_rprev(HP_INFO *info, uchar *record)
       custom_arg.keyseg = keyinfo->seg;
       custom_arg.key_length = keyinfo->length;
       custom_arg.search_flag = SEARCH_SAME;
+      info->last_find_flag= HA_READ_KEY_OR_PREV;
       pos = tree_search_key(&keyinfo->rb_tree, info->lastkey, info->parents, 
                            &info->last_pos, info->last_find_flag, &custom_arg);
     }

storage/heap/hp_scan.c

@@ -31,6 +31,8 @@ int heap_scan_init(register HP_INFO *info)
   info->current_record= (ulong) ~0L;		/* No current record */
   info->update=0;
   info->next_block=0;
+  info->key_version= info->s->key_version;
+  info->file_version= info->s->file_version;
   DBUG_RETURN(0);
 }
 

storage/heap/hp_update.c

@@ -21,7 +21,7 @@ int heap_update(HP_INFO *info, const uchar *old, const uchar *heap_new)
 {
   HP_KEYDEF *keydef, *end, *p_lastinx;
   uchar *pos;
-  my_bool auto_key_changed= 0;
+  my_bool auto_key_changed= 0, key_changed= 0;
   HP_SHARE *share= info->s;
   DBUG_ENTER("heap_update");
 
@@ -54,6 +54,8 @@ int heap_update(HP_INFO *info, const uchar *old, const uchar *heap_new)
 #endif
   if (auto_key_changed)
     heap_update_auto_increment(info, heap_new);
+  if (key_changed)
+    share->key_version++;
   DBUG_RETURN(0);
 
  err:

storage/heap/hp_write.c

@@ -56,6 +56,7 @@ int heap_write(HP_INFO *info, const uchar *record)
   pos[share->reclength]=1;		/* Mark record as not deleted */
   if (++share->records == share->blength)
     share->blength+= share->blength;
+  info->s->key_version++;
   info->current_ptr=pos;
   info->current_hash_ptr=0;
   info->update|=HA_STATE_AKTIV;