merged

Docs/manual.texi

@@ -411,6 +411,7 @@ MySQL Language Reference
 * SET OPTION::                  @code{SET OPTION} syntax
 * SET TRANSACTION::             @code{SET TRANSACTION} syntax
 * GRANT::                       @code{GRANT} and @code{REVOKE} syntax
+* HANDLER::                     @code{HANDLER} syntax
 * CREATE INDEX::                @code{CREATE INDEX} syntax
 * DROP INDEX::                  @code{DROP INDEX} syntax
 * Comments::                    Comment syntax
@@ -13653,6 +13654,7 @@ to restart @code{mysqld} with @code{--skip-grant-tables} to run
 * SET OPTION::                  @code{SET OPTION} syntax
 * SET TRANSACTION::             @code{SET TRANSACTION} syntax
 * GRANT::                       @code{GRANT} and @code{REVOKE} syntax
+* HANDLER::                     @code{HANDLER} syntax
 * CREATE INDEX::                @code{CREATE INDEX} syntax
 * DROP INDEX::                  @code{DROP INDEX} syntax
 * Comments::                    Comment syntax
@@ -22615,7 +22617,7 @@ You can set the default isolation level for @code{mysqld} with
 
 @findex GRANT
 @findex REVOKE
-@node GRANT, CREATE INDEX, SET TRANSACTION, Reference
+@node GRANT, HANDLER, SET TRANSACTION, Reference
 @section @code{GRANT} and @code{REVOKE} Syntax
 
 @example
@@ -22843,11 +22845,52 @@ dropped only with explicit @code{REVOKE} commands or by manipulating the
 @strong{MySQL} grant tables.
 @end itemize
 
+@findex HANDLER
+@node HANDLER, CREATE INDEX, GRANT, Reference
+@section @code{HANDLER} Syntax
+
+@example
+HANDLER table OPEN [ AS alias ]
+HANDLER table READ index @{ = | >= | <= | < @} (value1, value2, ... )  [ WHERE ... ] [LIMIT ... ]
+HANDLER table READ index @{ FIRST | NEXT | PREV | LAST @} [ WHERE ... ] [LIMIT ... ]
+HANDLER table READ @{ FIRST | NEXT @}  [ WHERE ... ] [LIMIT ... ]
+HANDLER table CLOSE
+@end example
+
+The @code{HANDLER} statement provides direct access to @strong{MySQL} table
+interface, bypassing SQL optimizer. Thus, it is faster then SELECT.
+
+The first form of @code{HANDLER} statement opens a table, making
+in accessible via the following @code{HANDLER ... READ} routines.
+
+The second form fetches one (or, specified by @code{LIMIT} clause) row
+where the index specified complies to the condition and @code{WHERE}
+condition is met. If the index consists of several parts (spans over
+several columns) the values are specified in comma-separated list,
+providing values only for few first columns is possible.
+
+The third form fetches one (or, specified by @code{LIMIT} clause) row
+from the table in index order, matching @code{WHERE} condition.
+
+The fourth form (without index specification) fetches one (or, specified
+by @code{LIMIT} clause) row from the table in natural row order (as stored
+in data file) matching @code{WHERE} condition. It is faster than
+@code{HANDLER table READ index} when full table scan is desired.
+
+The last form closes the table, opened with @code{HANDLER ... OPEN}.
+
+@code{HANDLER} is somewhat low-level statement, for example it does not
+provide consistency. That is @code{HANDLER ... OPEN} does @strong{not}
+takes a snapshot of the table, and does @strong{not} locks the table. The
+above means,  that after @code{HANDLER ... OPEN} table data can be
+modified (by this or other thread) and these modifications may appear only
+partially in @code{HANDLER ... NEXT} or @code{HANDLER ... PREV} scans.
+
 @cindex indexes
 @cindex indexes, multi-part
 @cindex multi-part index
 @findex CREATE INDEX
-@node CREATE INDEX, DROP INDEX, GRANT, Reference
+@node CREATE INDEX, DROP INDEX, HANDLER, Reference
 @section @code{CREATE INDEX} Syntax
 
 @example
@@ -40814,205 +40857,6 @@ started to read and apply updates from the master.
 @code{mysqladmin processlist} only shows the connection, @code{INSERT DELAYED},
 and replication threads.
 
-@cindex searching, full-text
-@cindex full-text search
-@cindex FULLTEXT
-@node MySQL full-text search, MySQL test suite, MySQL threads, MySQL internals
-@section MySQL Full-text Search
-
-Since Version 3.23.23, @strong{MySQL} has support for full-text indexing
-and searching.  Full-text indexes in @strong{MySQL} are an index of type 
-@code{FULLTEXT}.  @code{FULLTEXT} indexes can be created from @code{VARCHAR} 
-and @code{TEXT} columns at @code{CREATE TABLE} time or added later with 
-@code{ALTER TABLE} or @code{CREATE INDEX}.  For large datasets, adding 
-@code{FULLTEXT} index with @code{ALTER TABLE} (or @code{CREATE INDEX}) would 
-be much faster than inserting rows into the empty table with a @code{FULLTEXT} 
-index.
-
-Full-text search is performed with the @code{MATCH} function.
-
-@example
-mysql> CREATE TABLE t (a VARCHAR(200), b TEXT, FULLTEXT (a,b));
-Query OK, 0 rows affected (0.00 sec)
-
-mysql> INSERT INTO t VALUES
-    ->   ('MySQL has now support', 'for full-text search'),
-    ->   ('Full-text indexes', 'are called collections'),
-    ->   ('Only MyISAM tables','support collections'),
-    ->   ('Function MATCH ... AGAINST()','is used to do a search'),
-    ->   ('Full-text search in MySQL', 'implements vector space model');
-Query OK, 5 rows affected (0.00 sec)
-Records: 5  Duplicates: 0  Warnings: 0
-
-mysql> SELECT * FROM t WHERE MATCH (a,b) AGAINST ('MySQL');
-+---------------------------+-------------------------------+
-| a                         | b                             |
-+---------------------------+-------------------------------+
-| MySQL has now support     | for full-text search          |
-| Full-text search in MySQL | implements vector-space-model |
-+---------------------------+-------------------------------+
-2 rows in set (0.00 sec)
-
-mysql> SELECT *,MATCH a,b AGAINST ('collections support') as x FROM t;
-+------------------------------+-------------------------------+--------+
-| a                            | b                             | x      |
-+------------------------------+-------------------------------+--------+
-| MySQL has now support        | for full-text search          | 0.3834 |
-| Full-text indexes            | are called collections        | 0.3834 |
-| Only MyISAM tables           | support collections           | 0.7668 |
-| Function MATCH ... AGAINST() | is used to do a search        |      0 |
-| Full-text search in MySQL    | implements vector space model |      0 |
-+------------------------------+-------------------------------+--------+
-5 rows in set (0.00 sec)
-@end example
-
-The function @code{MATCH} matches a natural language query @code{AGAINST} 
-a text collection (which is simply the columns that are covered by a 
-@strong{FULLTEXT} index).  For every row in a table it returns relevance - 
-a similarity measure between the text in that row (in the columns that are 
-part of the collection) and the query.  When it is used in a @code{WHERE} 
-clause (see example above) the rows returned are automatically sorted with 
-relevance decreasing.  Relevance is a non-negative floating-point number. 
-Zero relevance means no similarity.  Relevance is computed based on the 
-number of words in the row, the number of unique words in that row, the 
-total number of words in the collection, and the number of documents (rows) 
-that contain a particular word.
-
-MySQL uses a very simple parser to split text into words.  A ``word'' is
-any sequence of letters, numbers, @samp{'}, and @samp{_}.  Any ``word''
-that is present in the stopword list or just too short (3 characters
-or less) is ignored.
-
-Every correct word in the collection and in the query is weighted,
-according to its significance in the query or collection.  This way, a
-word that is present in many documents will have lower weight (and may
-even have a zero weight), because it has lower semantic value in this
-particular collection.  Otherwise, if the word is rare, it will receive a
-higher weight.  The weights of the words are then combined to compute the
-relevance of the row.
-
-Such a technique works best with large collections (in fact, it was
-carefully tuned this way).  For very small tables, word distribution
-does not reflect adequately their semantical value, and this model
-may sometimes produce bizarre results.
-
-For example, search for the word "search" will produce no results in the
-above example. Word "search" is present in more than half of rows, and
-as such, is effectively treated as a stopword (that is, with semantical value
-zero).  It is, really, the desired behavior - a natural language query
-should not return every other row in 1GB table.
-
-A word that matches half of rows in a table is less likely to locate relevant
-documents.  In fact, it will most likely find plenty of irrelevant documents.
-We all know this happens far too often when we are trying to find something on
-the Internet with a search engine.  It is with this reasoning that such rows 
-have been assigned a low semantical value in @strong{a particular dataset}.
-
-@menu
-* Fulltext Fine-tuning::        
-* Fulltext features to appear in MySQL 4.0::  
-* Fulltext TODO::               
-@end menu
-
-@node Fulltext Fine-tuning, Fulltext features to appear in MySQL 4.0, MySQL full-text search, MySQL full-text search
-@subsection Fine-tuning MySQL Full-text Search
-
-Unfortunately, full-text search has no user-tunable parameters yet,
-although adding some is very high on the TODO.  However, if you have a 
-@strong{MySQL} source distribution (@xref{Installing source}.), you can 
-somewhat alter the full-text search behavior.
-
-Note that full-text search was carefully tuned for the best searching
-effectiveness.  Modifying the default behavior will, in most cases,
-only make the search results worse.  Do not alter the @strong{MySQL} sources
-unless you know what you are doing!
-
-@itemize
-
-@item
-Minimal length of word to be indexed is defined in
-@code{myisam/ftdefs.h} file by the line
-@example
-#define MIN_WORD_LEN 4
-@end example
-Change it to the value you prefer, recompile @strong{MySQL}, and rebuild
-your @code{FULLTEXT} indexes.
-
-@item
-The stopword list is defined in @code{myisam/ft_static.c}
-Modify it to your taste, recompile @strong{MySQL} and rebuild
-your @code{FULLTEXT} indexes.
-
-@item
-The 50% threshold is caused by the particular weighting scheme chosen. To 
-disable it, change the following line in @code{myisam/ftdefs.h}:
-@example
-#define GWS_IN_USE GWS_PROB
-@end example
-to
-@example
-#define GWS_IN_USE GWS_FREQ
-@end example
-and recompile @strong{MySQL}.
-There is no need to rebuild the indexes in this case.
-
-@end itemize
-
-@node Fulltext features to appear in MySQL 4.0, Fulltext TODO, Fulltext Fine-tuning, MySQL full-text search
-@subsection New Features of Full-text Search to Appear in MySQL 4.0
-
-This section includes a list of the fulltext features that are already
-implemented in the 4.0 tree. It explains
-@strong{More functions for full-text search} entry of @ref{TODO MySQL 4.0}.
-
-@itemize @bullet
-@item @code{REPAIR TABLE} with @code{FULLTEXT} indexes,
-@code{ALTER TABLE} with @code{FULLTEXT} indexes, and
-@code{OPTIMIZE TABLE} with @code{FULLTEXT} indexes are now
-up to 100 times faster.
-
-@item @code{MATCH ... AGAINST} now supports the following 
-@strong{boolean operators}:
-
-@itemize @bullet
-@item @code{+}word means the that word @strong{must} be present in every
-row returned.
-@item @code{-}word means the that word @strong{must not} be present in every
-row returned.
-@item @code{<} and @code{>} can be used to decrease and increase word 
-weight in the query.
-@item @code{~} can be used to assign a @strong{negative} weight to a noise 
-word.
-@item @code{*} is a truncation operator.
-@end itemize
-
-Boolean search utilizes a more simplistic way of calculating the relevance,
-that does not have a 50% threshold.
-
-@item Searches are now up to 2 times faster due to optimized search algorithm.
-
-@item Utility program @code{ft_dump} added for low-level @code{FULLTEXT}
-index operations (querying/dumping/statistics).
-
-@end itemize
-
-@node Fulltext TODO,  , Fulltext features to appear in MySQL 4.0, MySQL full-text search
-@subsection Full-text Search TODO
-
-@itemize @bullet
-@item Make all operations with @code{FULLTEXT} index @strong{faster}.
-@item Support for braces @code{()} in boolean fulltext search.
-@item Support for "always-index words". They could be any strings
-the user wants to treat as words, examples are "C++", "AS/400", "TCP/IP", etc.
-@item Support for fulltext search in @code{MERGE} tables.
-@item Support for multi-byte charsets.
-@item Make stopword list to depend of the language of the data.
-@item Stemming (dependent of the language of the data, of course).
-@item Generic user-suppied UDF (?) preparser.
-@item Make the model more flexible (by adding some adjustable
-parameters to @code{FULLTEXT} in @code{CREATE/ALTER TABLE}).
-@end itemize
-
 @cindex mysqltest, MySQL Test Suite
 @cindex testing mysqld, mysqltest
 @node MySQL test suite,  , MySQL threads, MySQL internals

mysql-test/r/handler.result

+a	b
+14	aaa
+a	b
+15	bbb
+a	b
+16	ccc
+a	b
+15	bbb
+a	b
+22	iii
+a	b
+21	hhh
+a	b
+20	ggg
+a	b
+14	aaa
+a	b
+a	b
+22	iii
+a	b
+21	hhh
+a	b
+22	iii
+a	b
+a	b
+15	bbb

mysql-test/t/handler.test

+#
+# test of HANDLER ...
+#
+
+drop table if exists t1;
+create table t1 (a int, b char(10), key a(a), key b(a,b));
+insert into t1 values
+(17,"ddd"),(18,"eee"),(19,"fff"),(19,"yyy"),
+(14,"aaa"),(15,"bbb"),(16,"ccc"),(16,"xxx"),
+(20,"ggg"),(21,"hhh"),(22,"iii");
+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 a=(15);
+handler t2 read a=(16);
+
+!$1070 handler t2 read a=(19,"fff");
+
+handler t2 read b=(19,"fff");
+handler t2 read b=(19,"yyy");
+handler t2 read b=(19);
+
+!$1109 handler t1 read a last;
+
+handler t2 read a=(11);
+handler t2 read a>=(11);
+
+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);
+
+handler t2 read a first limit 5;
+handler t2 read a next  limit 3;
+handler t2 read a prev  limit 10;
+
+handler t2 read a>=(16) limit 4;
+handler t2 read a>=(16) limit 2,2;
+handler t2 read a last  limit 3;
+
+handler t2 read a=(19);
+handler t2 read a=(19) where b="yyy";
+
+handler t2 read first;
+handler t2 read next;
+handler t2 read next;
+handler t2 read last;
+
+handler t2 close;
+drop table if exists t1;

sql/Makefile.am

@@ -56,7 +56,7 @@ noinst_HEADERS =	item.h item_func.h item_sum.h item_cmpfunc.h \
 			sql_select.h structs.h table.h sql_udf.h hash_filo.h\
 			lex.h lex_symbol.h sql_acl.h sql_crypt.h md5.h \
                         log_event.h mini_client.h sql_repl.h slave.h
-mysqld_SOURCES =	sql_lex.cc \
+mysqld_SOURCES =	sql_lex.cc sql_handler.cc \
 			item.cc item_sum.cc item_buff.cc item_func.cc \
 			item_cmpfunc.cc item_strfunc.cc item_timefunc.cc \
 			thr_malloc.cc item_create.cc \

sql/lex.h

@@ -82,6 +82,7 @@ static SYMBOL symbols[] = {
   { "CHANGED",		SYM(CHANGED),0,0},
   { "CHECK",		SYM(CHECK_SYM),0,0},
   { "CHECKSUM",		SYM(CHECKSUM_SYM),0,0},
+  { "CLOSE",		SYM(CLOSE_SYM),0,0},
   { "COLUMN",		SYM(COLUMN_SYM),0,0},
   { "COLUMNS",		SYM(COLUMNS),0,0},
   { "COMMENT",		SYM(COMMENT_SYM),0,0},
@@ -152,6 +153,7 @@ static SYMBOL symbols[] = {
   { "GRANTS",	        SYM(GRANTS),0,0},
   { "GROUP",		SYM(GROUP),0,0},
   { "HAVING",		SYM(HAVING),0,0},
+  { "HANDLER",		SYM(HANDLER_SYM),0,0},
   { "HEAP",		SYM(HEAP_SYM),0,0},
   { "HIGH_PRIORITY",	SYM(HIGH_PRIORITY),0,0},
   { "HOUR",		SYM(HOUR_SYM),0,0},
@@ -185,6 +187,7 @@ static SYMBOL symbols[] = {
   { "KEY",		SYM(KEY_SYM),0,0},
   { "KEYS",		SYM(KEYS),0,0},
   { "KILL",		SYM(KILL_SYM),0,0},
+  { "LAST",		SYM(LAST_SYM),0,0},
   { "LAST_INSERT_ID",	SYM(LAST_INSERT_ID),0,0},
   { "LEADING",		SYM(LEADING),0,0},
   { "LEFT",		SYM(LEFT),0,0},
@@ -226,11 +229,12 @@ static SYMBOL symbols[] = {
   { "MYISAM",		SYM(MYISAM_SYM),0,0},
   { "NATURAL",		SYM(NATURAL),0,0},
   { "NATIONAL",		SYM(NATIONAL_SYM),0,0},
+  { "NEXT",		SYM(NEXT_SYM),0,0},
   { "NCHAR",		SYM(NCHAR_SYM),0,0},
-  { "NUMERIC",		SYM(NUMERIC_SYM),0,0},
   { "NO",		SYM(NO_SYM),0,0},
   { "NOT",		SYM(NOT),0,0},
   { "NULL",		SYM(NULL_SYM),0,0},
+  { "NUMERIC",		SYM(NUMERIC_SYM),0,0},
   { "ON",		SYM(ON),0,0},
   { "OPEN",		SYM(OPEN_SYM),0,0},
   { "OPTIMIZE",		SYM(OPTIMIZE),0,0},
@@ -245,6 +249,7 @@ static SYMBOL symbols[] = {
   { "PASSWORD",		SYM(PASSWORD),0,0},
   { "PURGE",		SYM(PURGE),0,0},
   { "PRECISION",	SYM(PRECISION),0,0},
+  { "PREV",		SYM(PREV_SYM),0,0},
   { "PRIMARY",		SYM(PRIMARY_SYM),0,0},
   { "PROCEDURE",	SYM(PROCEDURE),0,0},
   { "PROCESS"	,	SYM(PROCESS),0,0},

sql/mysql_priv.h

@@ -385,6 +385,12 @@ int mysqld_show_status(THD *thd);
 int mysqld_show_variables(THD *thd,const char *wild);
 int mysqld_show(THD *thd, const char *wild, show_var_st *variables);
 
+/* sql_handler.cc */
+int mysql_ha_open(THD *thd, TABLE_LIST *tables);
+int mysql_ha_close(THD *thd, TABLE_LIST *tables);
+int mysql_ha_read(THD *, TABLE_LIST *,enum enum_ha_read_modes,char *,
+               List<Item> *,enum ha_rkey_function,Item *,ha_rows,ha_rows);
+
 /* sql_base.cc */
 void set_item_name(Item *item,char *pos,uint length);
 bool add_field_to_list(char *field_name, enum enum_field_types type,
@@ -406,6 +412,8 @@ TABLE *unlink_open_table(THD *thd,TABLE *list,TABLE *find);
 SQL_SELECT *make_select(TABLE *head, table_map const_tables,
 			table_map read_tables, COND *conds, int *error);
 Item ** find_item_in_list(Item *item,List<Item> &items);
+bool insert_fields(THD *thd,TABLE_LIST *tables, const char *table_name,
+	      List_iterator<Item> *it);
 bool setup_tables(TABLE_LIST *tables);
 int setup_fields(THD *thd,TABLE_LIST *tables,List<Item> &item,
 		 bool set_query_id,List<Item> *sum_func_list);

sql/sql_base.cc

@@ -34,8 +34,6 @@ HASH open_cache;				/* Used by mysql_test */
 
 static int open_unireg_entry(THD *thd,TABLE *entry,const char *db,
 			     const char *name, const char *alias, bool locked);
-static bool insert_fields(THD *thd,TABLE_LIST *tables, const char *table_name,
-			  List_iterator<Item> *it);
 static void free_cache_entry(TABLE *entry);
 static void mysql_rm_tmp_tables(void);
 static key_map get_key_map_from_key_list(TABLE *table,
@@ -1815,7 +1813,7 @@ static key_map get_key_map_from_key_list(TABLE *table,
 **	Returns pointer to last inserted field if ok
 ****************************************************************************/
 
-static bool
+bool
 insert_fields(THD *thd,TABLE_LIST *tables, const char *table_name,
 	      List_iterator<Item> *it)
 {

sql/sql_class.cc

@@ -85,7 +85,8 @@ THD::THD():user_time(0),fatal_error(0),last_insert_id_used(0),
   query_length=col_access=0;
   query_error=0;
   next_insert_id=last_insert_id=0;
-  open_tables=temporary_tables=0;
+  open_tables=temporary_tables=handler_tables=0;
+  handler_items=0;
   tmp_table=0;
   lock=locked_tables=0;
   used_tables=0;
@@ -163,6 +164,11 @@ THD::~THD()
     lock=locked_tables; locked_tables=0;
     close_thread_tables(this);
   }
+  if (handler_tables)
+  {
+    open_tables=handler_tables; handler_tables=0;
+    close_thread_tables(this);
+  }
   close_temporary_tables(this);
 #ifdef USING_TRANSACTIONS
   if (opt_using_transactions)

sql/sql_class.h

@@ -24,7 +24,7 @@
 class Query_log_event;
 class Load_log_event;
 
-
+enum enum_ha_read_modes { RFIRST, RNEXT, RPREV, RLAST, RKEY };
 enum enum_duplicates { DUP_ERROR, DUP_REPLACE, DUP_IGNORE };
 enum enum_log_type { LOG_CLOSED, LOG_NORMAL, LOG_NEW, LOG_BIN };
 
@@ -231,7 +231,7 @@ public:
   const   char *proc_info;
   uint	  client_capabilities,max_packet_length;
   uint	  master_access,db_access;
-  TABLE   *open_tables,*temporary_tables;
+  TABLE   *open_tables,*temporary_tables, *handler_tables;
   MYSQL_LOCK *lock,*locked_tables;
   ULL	  *ull;
   struct st_my_thread_var *mysys_var;
@@ -253,7 +253,7 @@ public:
 #ifdef HAVE_GEMINI_DB
   struct st_gemini gemini;
 #endif
-  Item	     *free_list;
+  Item	     *free_list, *handler_items;
   CONVERT    *convert_set;
   Field      *dupp_field;
 #ifndef __WIN__

sql/sql_handler.cc

+/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult 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
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+
+/* HANDLER ... commands - direct access to ISAM */
+
+#include <assert.h>
+#include "mysql_priv.h"
+#include "sql_select.h"
+
+/* TODO:
+  HANDLER blabla OPEN [ AS foobar ] [ (column-list) ]
+  
+  the most natural (easiest, fastest) way to do it is to
+  compute List<Item> field_list not in mysql_ha_read
+  but in mysql_ha_open, and then store it in TABLE structure.
+  
+  The problem here is that mysql_parse calls free_item to free all the
+  items allocated at the end of every query. The workaround would to
+  keep two item lists per THD - normal free_list and handler_items.
+  The second is to be freeed only on thread end. mysql_ha_open should
+  then do { handler_items=concat(handler_items, free_list); free_list=0; }
+  
+  But !!! do_cammand calls free_root at the end of every query and frees up
+  all the sql_alloc'ed memory. It's harder to work around...
+ */
+
+#define HANDLER_TABLES_HACK(thd) {      \
+  TABLE *tmp=thd->open_tables;          \
+  thd->open_tables=thd->handler_tables; \
+  thd->handler_tables=tmp; }
+
+static TABLE *find_table_by_name(THD *thd, char *db, char *table_name);
+
+int mysql_ha_open(THD *thd, TABLE_LIST *tables)
+{
+  HANDLER_TABLES_HACK(thd);
+  int err=open_tables(thd,tables);
+  HANDLER_TABLES_HACK(thd);
+  if (err)
+    return -1;
+  
+  send_ok(&thd->net);
+  return 0;
+}
+
+int mysql_ha_close(THD *thd, TABLE_LIST *tables)
+{
+  /* Perhaps, we should close table here.
+     But it's not easy - *tables is a single-linked list, designed
+     to be closed at all once.
+     So, why bother ? All the tables will be closed at thread exit.
+   */
+  send_ok(&thd->net);
+  return 0;
+}
+
+static enum enum_ha_read_modes rkey_to_rnext[]= 
+    { RNEXT, RNEXT, RPREV, RNEXT, RPREV, RNEXT, RPREV };
+    
+int mysql_ha_read(THD *thd, TABLE_LIST *tables,
+    enum enum_ha_read_modes mode, char *keyname, List<Item> *key_expr,
+    enum ha_rkey_function ha_rkey_mode, Item *cond,
+    ha_rows select_limit,ha_rows offset_limit)
+{
+  int err, keyno=-1;
+  TABLE *table=find_table_by_name(thd, tables->db, tables->name);
+  if (!table)
+  {
+    my_printf_error(ER_UNKNOWN_TABLE,ER(ER_UNKNOWN_TABLE),MYF(0),
+        tables->name,"HANDLER");
+    return -1;
+  }
+  tables->table=table;
+
+  if (cond && cond->fix_fields(thd,tables))
+    return -1;
+  
+  if (keyname)
+  {
+    if ((keyno=find_type(keyname, &table->keynames, 1+2)-1)<0)
+    {
+      my_printf_error(ER_KEY_DOES_NOT_EXITS,ER(ER_KEY_DOES_NOT_EXITS),MYF(0),
+          keyname,tables->name);
+      return -1;
+    }
+  }
+
+  List<Item> list;
+  list.push_front(new Item_field(NULL,NULL,"*"));
+  List_iterator<Item> it(list);
+  it++;
+
+  insert_fields(thd,tables,tables->name,&it);
+
+  table->file->index_init(keyno);
+
+  select_limit+=offset_limit;
+  send_fields(thd,list,1);
+  
+  MYSQL_LOCK *lock=mysql_lock_tables(thd,&tables->table,1);
+
+  for (uint num_rows=0; num_rows < select_limit; )
+  {
+    switch(mode)
+    {
+      case RFIRST:
+         err=keyname ?
+             table->file->index_first(table->record[0]) :
+             table->file->rnd_init(1) ||
+             table->file->rnd_next(table->record[0]);
+         mode=RNEXT;
+         break;
+      case RLAST:
+         dbug_assert(keyname != 0);
+         err=table->file->index_last(table->record[0]);
+         mode=RPREV;
+         break;
+      case RNEXT:
+         err=keyname ?
+             table->file->index_next(table->record[0]) :
+             table->file->rnd_next(table->record[0]);
+         break;
+      case RPREV:
+         dbug_assert(keyname != 0);
+         err=table->file->index_prev(table->record[0]);
+         break;
+      case RKEY:
+        {
+          dbug_assert(keyname != 0);
+          KEY *keyinfo=table->key_info+keyno;
+	  KEY_PART_INFO *key_part=keyinfo->key_part;
+          uint key_len;
+          byte *key;
+          if (key_expr->elements > keyinfo->key_parts)
+          {
+             my_printf_error(ER_TOO_MANY_KEY_PARTS,ER(ER_TOO_MANY_KEY_PARTS),
+                 MYF(0),keyinfo->key_parts);
+             goto err;
+          }
+          List_iterator<Item> it_ke(*key_expr);
+	  Item *item;
+          for (key_len=0 ; (item=it_ke++) ; key_part++)
+          {
+            item->save_in_field(key_part->field);
+            key_len+=key_part->store_length;
+          }
+          if (!(key=sql_calloc(ALIGN_SIZE(key_len))))
+          {
+            send_error(&thd->net,ER_OUTOFMEMORY);
+            goto err; 
+          }
+          key_copy(key, table, keyno, key_len);
+          err=table->file->index_read(table->record[0],
+              key,key_len,ha_rkey_mode);
+          mode=rkey_to_rnext[(int)ha_rkey_mode];
+          break;
+        }
+      default:
+          send_error(&thd->net,ER_ILLEGAL_HA);
+          goto err; 
+    }
+
+    if (err)
+    {
+      if (err != HA_ERR_KEY_NOT_FOUND && err != HA_ERR_END_OF_FILE)
+      {
+        sql_print_error("mysql_ha_read: Got error %d when reading table",
+                        err);
+        table->file->print_error(err,MYF(0));
+        goto err;
+      }
+      goto ok;
+    }
+    if (cond)
+    { 
+      err=err;
+      if(!cond->val_int())
+        continue;
+    }
+    if (num_rows>=offset_limit)
+    {
+      if (!err)
+      {
+        String *packet = &thd->packet;
+        Item *item;
+        packet->length(0);
+        it.rewind();
+        while ((item=it++))
+        {
+          if (item->send(packet))
+          {
+            packet->free();                             // Free used
+            my_error(ER_OUT_OF_RESOURCES,MYF(0));
+            goto err;
+          }
+        }
+        my_net_write(&thd->net, (char*)packet->ptr(), packet->length());
+      }
+    }
+    num_rows++;
+  }
+ok:
+  mysql_unlock_tables(thd,lock);
+  send_eof(&thd->net);
+  return 0;
+err:
+  mysql_unlock_tables(thd,lock);
+  return -1;
+}
+
+/**************************************************************************
+   2Monty: It could easily happen, that the following service functions are
+   already defined somewhere in the code, but I failed to find them.
+   If this is the case, just say a word and I'll use old functions here.
+**************************************************************************/
+
+/* Note: this function differs from find_locked_table() because we're looking
+   here for alias, not real table name 
+ */
+static TABLE *find_table_by_name(THD *thd, char *db, char *table_name)
+{
+  int dblen;
+  
+  if (!db || ! *db) db=thd->db;
+  if (!db || ! *db) db="";
+  dblen=strlen(db);  
+  
+  for (TABLE *table=thd->handler_tables; table ; table=table->next)
+  {
+    if (!memcmp(table->table_cache_key, db, dblen) &&
+        !my_strcasecmp(table->table_name,table_name))
+      return table;
+  }
+  return(0);
+}

sql/sql_lex.h

@@ -53,7 +53,8 @@ enum enum_sql_command {
   SQLCOM_BEGIN, SQLCOM_LOAD_MASTER_TABLE, SQLCOM_CHANGE_MASTER,
   SQLCOM_RENAME_TABLE, SQLCOM_BACKUP_TABLE, SQLCOM_RESTORE_TABLE,
   SQLCOM_RESET, SQLCOM_PURGE, SQLCOM_SHOW_BINLOGS,
-  SQLCOM_SHOW_OPEN_TABLES
+  SQLCOM_SHOW_OPEN_TABLES,
+  SQLCOM_HA_OPEN, SQLCOM_HA_CLOSE, SQLCOM_HA_READ
 };
 
 enum lex_states { STATE_START, STATE_CHAR, STATE_IDENT,
@@ -141,6 +142,8 @@ typedef struct st_lex {
   enum lex_states next_state;
   enum enum_duplicates duplicates;
   enum enum_tx_isolation tx_isolation;
+  enum enum_ha_read_modes ha_read_mode;
+  enum ha_rkey_function ha_rkey_mode;
   uint in_sum_expr,grant,grant_tot_col,which_columns, sort_default;
   thr_lock_type lock_option;
   bool	create_refs,drop_primary,drop_if_exists,local_file;

sql/sql_parse.cc

@@ -2008,6 +2008,24 @@ mysql_execute_command(void)
       res = mysql_show_grants(thd,lex->grant_user);
     }
     break;
+  case SQLCOM_HA_OPEN:
+    if (check_db_used(thd,tables) || check_table_access(thd,SELECT_ACL, tables))
+      goto error;
+    res = mysql_ha_open(thd, tables);
+    break;
+  case SQLCOM_HA_CLOSE:
+    if (check_db_used(thd,tables))
+      goto error;
+    res = mysql_ha_close(thd, tables);
+    break;
+  case SQLCOM_HA_READ:
+    if (check_db_used(thd,tables) || check_table_access(thd,SELECT_ACL, tables))
+      goto error;
+    res = mysql_ha_read(thd, tables, lex->ha_read_mode, lex->backup_dir,
+                    lex->insert_list, lex->ha_rkey_mode, lex->where,
+	            lex->select_limit, lex->offset_limit);
+    break;
+
   case SQLCOM_BEGIN:
     if (end_active_trans(thd))
     {

sql/sql_yacc.yy

@@ -110,6 +110,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	CHECKSUM_SYM
 %token	CHECK_SYM
 %token	COALESCE
+%token	CLOSE_SYM
 %token	COLUMNS
 %token	COLUMN_SYM
 %token	COMMENT_SYM
@@ -193,6 +194,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	GROUP_UNIQUE_USERS
 %token	GT_SYM
 %token	HAVING
+%token	HANDLER_SYM
 %token	HEAP_SYM
 %token	HEX_NUM
 %token	HIGH_PRIORITY
@@ -222,6 +224,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	KEY_SYM
 %token	KILL_SYM
 %token	LAST_INSERT_ID
+%token	LAST_SYM
 %token	LE
 %token	LEADING
 %token	LEAST_SYM
@@ -271,6 +274,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	NATURAL
 %token	NCHAR_SYM
 %token	NE
+%token	NEXT_SYM
 %token	NOT
 %token	NOW_SYM
 %token	NO_SYM
@@ -292,6 +296,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	PASSWORD
 %token	POSITION_SYM
 %token	PRECISION
+%token	PREV_SYM
 %token	PRIMARY_SYM
 %token	PRIVILEGES
 %token	PROCEDURE
@@ -403,6 +408,43 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	USE_SYM
 %token	USING
 %token	VALUES
+%token	VARIABLES
+%token	WHERE
+%token	WITH
+%token	WRITE_SYM
+%token  COMPRESSED_SYM
+
+%token	BIGINT
+%token	BLOB_SYM
+%token	CHAR_SYM
+%token  CHANGED
+%token	DATETIME
+%token	DATE_SYM
+%token	DECIMAL_SYM
+%token	DOUBLE_SYM
+%token	ENUM
+%token	FAST_SYM
+%token	FLOAT_SYM
+%token	INT_SYM
+%token	LONGBLOB
+%token	LONGTEXT
+%token	MEDIUMBLOB
+%token	MEDIUMINT
+%token	MEDIUMTEXT
+%token	NUMERIC_SYM
+%token	PRECISION
+%token  QUICK
+%token	REAL
+%token	SMALLINT
+%token	STRING_SYM
+%token	TEXT_SYM
+%token	TIMESTAMP
+%token	TIME_SYM
+%token	TINYBLOB
+%token	TINYINT
+%token	TINYTEXT
+%token	UNSIGNED
+>>>>>>> BitKeeper/tmp/sql_yacc.yy_serg@1.85
 %token	VARBINARY
 %token	VARCHAR
 %token	VARIABLES
@@ -527,13 +569,13 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 	select_item_list select_item values_list no_braces
 	limit_clause delete_limit_clause fields opt_values values
 	procedure_list procedure_list2 procedure_item
-        when_list2 expr_list2
+        when_list2 expr_list2 handler
 	opt_precision opt_ignore opt_column opt_restrict
 	grant revoke set lock unlock string_list field_options field_option
 	field_opt_list opt_binary table_lock_list table_lock varchar
 	references opt_on_delete opt_on_delete_list opt_on_delete_item use
 	opt_delete_options opt_delete_option
-	opt_outer table_list table opt_option opt_place opt_low_priority
+	opt_outer table_list table_name opt_option opt_place opt_low_priority
 	opt_attribute opt_attribute_list attribute column_list column_list_id
 	opt_column_list grant_privileges opt_table user_list grant_option
 	grant_privilege grant_privilege_list
@@ -541,7 +583,8 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 	equal optional_braces opt_key_definition key_usage_list2
 	opt_mi_check_type opt_to mi_check_types normal_join
 	table_to_table_list table_to_table opt_table_list opt_as
-	END_OF_INPUT
+	handler_rkey_function handler_rkey_mode handler_read_or_scan
+        END_OF_INPUT
 
 %type <NONE>
 	'-' '+' '*' '/' '%' '(' ')'
@@ -590,6 +633,7 @@ verb_clause:
 	| slave
 	| show
 	| truncate
+	| handler
 	| unlock
 	| update
 	| use
@@ -1910,7 +1954,8 @@ order_dir:
 limit_clause:
 	/* empty */
 	{
-	  Lex->select_limit= current_thd->default_select_limit;
+	  Lex->select_limit= (Lex->sql_command == SQLCOM_HA_READ) ?
+             1 : current_thd->default_select_limit;
 	  Lex->offset_limit= 0L;
 	}
 	| LIMIT ULONG_NUM
@@ -2015,10 +2060,10 @@ drop:
 
 
 table_list:
-	table
-	| table_list ',' table
+	table_name
+	| table_list ',' table_name
 
-table:
+table_name:
 	table_ident
 	{ if (!add_table_to_list($1,NULL,1)) YYABORT; }
 
@@ -2051,7 +2096,7 @@ insert2:
 	| insert_table {}
 
 insert_table:
-	table
+	table_name
 	{
 	  Lex->field_list.empty();
 	  Lex->many_values.empty();
@@ -2550,6 +2595,7 @@ keyword:
 	| CHANGED		{}
 	| CHECKSUM_SYM		{}
 	| CHECK_SYM		{}
+	| CLOSE_SYM		{}
 	| COMMENT_SYM		{}
 	| COMMIT_SYM		{}
 	| COMMITTED_SYM		{}
@@ -2575,12 +2621,14 @@ keyword:
 	| GEMINI_SYM		{}
 	| GLOBAL_SYM		{}
 	| HEAP_SYM		{}
+	| HANDLER_SYM		{}
 	| HOSTS_SYM		{}
 	| HOUR_SYM		{}
 	| IDENTIFIED_SYM	{}
 	| ISOLATION		{}
 	| ISAM_SYM		{}
 	| INNOBASE_SYM		{}
+	| LAST_SYM		{}
 	| LEVEL_SYM		{}
 	| LOCAL_SYM		{}
 	| LOGS_SYM		{}
@@ -2603,10 +2651,12 @@ keyword:
 	| MYISAM_SYM		{}
 	| NATIONAL_SYM		{}
 	| NCHAR_SYM		{}
+	| NEXT_SYM		{}
 	| NO_SYM		{}
 	| OPEN_SYM		{}
 	| PACK_KEYS_SYM		{}
 	| PASSWORD		{}
+	| PREV_SYM		{}
 	| PROCESS		{}
 	| PROCESSLIST_SYM	{}
 	| QUICK			{}
@@ -2863,6 +2913,58 @@ unlock:
 	UNLOCK_SYM table_or_tables { Lex->sql_command=SQLCOM_UNLOCK_TABLES; }
 
 
+/*
+** Handler: direct access to ISAM functions
+*/
+
+handler:
+	HANDLER_SYM table_ident OPEN_SYM opt_table_alias
+	{
+	  Lex->sql_command = SQLCOM_HA_OPEN;
+	  if (!add_table_to_list($2,$4,0))
+	    YYABORT;
+	}
+	| HANDLER_SYM table_ident CLOSE_SYM
+	{
+	  Lex->sql_command = SQLCOM_HA_CLOSE;
+	  if (!add_table_to_list($2,0,0))
+	    YYABORT;
+	}
+	| HANDLER_SYM table_ident READ_SYM handler_read_or_scan
+	{
+	  Lex->sql_command = SQLCOM_HA_READ;
+	  if (!add_table_to_list($2,0,0))
+	    YYABORT;
+        }
+        where_clause limit_clause { }
+
+handler_read_or_scan:
+	handler_scan_function         { Lex->backup_dir= 0; }
+        | ident handler_rkey_function { Lex->backup_dir= $1.str; }
+
+handler_scan_function:
+	FIRST_SYM  { Lex->ha_read_mode = RFIRST; }
+	| NEXT_SYM { Lex->ha_read_mode = RNEXT;  }
+
+handler_rkey_function:
+	FIRST_SYM  { Lex->ha_read_mode = RFIRST; }
+	| NEXT_SYM { Lex->ha_read_mode = RNEXT;  }
+	| PREV_SYM { Lex->ha_read_mode = RPREV;  }
+	| LAST_SYM { Lex->ha_read_mode = RLAST;  }
+	| handler_rkey_mode
+	{
+	  Lex->ha_read_mode = RKEY;
+	  if (!(Lex->insert_list = new List_item))
+	    YYABORT;
+	} '(' values ')' { }
+
+handler_rkey_mode:
+	  EQ     { Lex->ha_rkey_mode=HA_READ_KEY_EXACT;   }
+	| GE     { Lex->ha_rkey_mode=HA_READ_KEY_OR_NEXT; }
+	| LE     { Lex->ha_rkey_mode=HA_READ_KEY_OR_PREV; }
+	| GT_SYM { Lex->ha_rkey_mode=HA_READ_AFTER_KEY;   }
+	| LT     { Lex->ha_rkey_mode=HA_READ_BEFORE_KEY;  }
+
 /* GRANT / REVOKE */
 
 revoke: