Commit 813fc410 authored by unknown's avatar unknown
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A fix and a test case for Bug#6513 "Test Suite: Values inserted by using 

cursor is interpreted latin1 character and Bug#9819 "Cursors: Mysql Server
Crash while fetching from table with 5 million records."
A fix for a possible memory leak when fetching into an SP cursor
in a long loop.
The patch uses a common implementation of cursors in the binary protocol and 
in stored procedures and implements materialized cursors.
For implementation details, see comments in sql_cursor.cc


include/my_sys.h:
  - declaration for multi_alloc_root
libmysqld/Makefile.am:
  - drop protocol_cursor.cc, add sql_cursor.cc (replaces the old
  implementation of cursors with a new one)
mysql-test/r/ctype_ujis.result:
  - test results fixed (a test case for Bug#6513)
mysql-test/r/sp-big.result:
  - test results fixed (a test case for Bug#9819)
mysql-test/t/ctype_ujis.test:
  Add a test case for Bug#6513 "Test Suite: Values inserted by using cursor is
   interpreted latin1 character"
mysql-test/t/sp-big.test:
  Add a restricted test case for Bug#9819 "Cursors: Mysql Server Crash
  while fetching from table with 5 million records."
mysys/my_alloc.c:
  - an implementation of multi_alloc_root; this is largely a copy-paste
    from mulalloc.c, but the function is small and there is no easy way
    to reuse the existing C function.
sql/Makefile.am:
  - add sql_cursor.h, sql_cursor.cc (a new implementation of stored procedure
  cursors) and drop protocol_cursor.cc (the old one)
sql/handler.cc:
  - now TABLE object has its mem_root always initialized.
    Adjust the implementation handler::ha_open
sql/item_subselect.cc:
  - adjust to the changed declaration of st_select_lex_unit::prepare
sql/protocol.h:
  - drop Protocol_cursor
sql/sp_head.cc:
  - move juggling with Query_arena::free_list and Item::next to
    sp_eval_func_item, as this is needed in 3 places already.
sql/sp_head.h:
  - declare a no-op implementation for cleanup_stmt in sp_instr_cpush.
    This method is needed for non-materializing cursors, which are yet not 
    used in stored procedures.
  - declaration for sp_eval_func_item
sql/sp_rcontext.cc:
  - reimplement sp_cursor using the new implementation of server side cursors.
  - use sp_eval_func_item to assign values of SP variables from the
    row fetched from a cursor. This should fix a possible memory leak in 
    the old implementation of sp_cursor::fetch
sql/sp_rcontext.h:
  - reimplement sp_cursor using the new implementation of server side cursors.
sql/sql_class.cc:
  - disable the functionality that closes transient cursors at commit/rollback;
    transient cursors are not used in 5.0, instead we use materialized ones.
    To be enabled in a later version.
sql/sql_class.h:
  - adjust to the rename Cursor -> Server_side_cursor
  - additional declarations of select_union used in materialized cursors
sql/sql_derived.cc:
  - reuse bits of tmp table code in UNION, derived tables, and materialized
    cursors
  - cleanup comments
sql/sql_lex.h:
  - declarations of auxiliary methods used by materialized cursors
  - a cleanup in st_select_lex_unit interface
sql/sql_list.h:
  - add an array operator new[] to class Sql_alloc
sql/sql_prepare.cc:
  - split the tight coupling of cursors and prepared statements to reuse 
    the same implementation in stored procedures
  - cleanups of error processing in Prepared_statement::{prepare,execute}
sql/sql_select.cc:
  - move the implementation of sensitive (non-materializing) cursors to 
    sql_cursor.cc
  - make temporary tables self-contained: the table, its record and fields
    are allocated in TABLE::mem_root. This implementation is not clean
    and resets thd->mem_root several times because of the way create_tmp_table 
    works (many additional things are done inside it).
  - adjust to the changed declaration of st_select_lex_unit::prepare
sql/sql_select.h:
  - move the declaration of sensitive (non-materializing) cursors to 
    sql_cursor.cc
sql/sql_union.cc:
  - move pieces of st_select_unit::prepare to select_union and st_table
    methods to be able to reuse code in the implementation of materialized
    cursors
sql/sql_view.cc:
  - adjust to the changed signature of st_select_lex_unit::prepare
sql/table.cc:
  - implement auxiliary st_table methods for use with temporary tables
sql/table.h:
  - add declarations for auxiliary methods of st_table used to work with 
   temporary tables
tests/mysql_client_test.c:
  - if cursors are materialized, a parallel update of the table used
    in the cursor may go through: update the test.
sql/sql_cursor.cc:
  New BitKeeper file ``sql/sql_cursor.cc'' -- implementation of server side
  cursors
sql/sql_cursor.h:
  New BitKeeper file ``sql/sql_cursor.h'' - declarations for
  server side cursors.
parent aa79e207

include/my_sys.h

+1 −0
Original line number Diff line number Diff line
@@ -775,6 +775,7 @@ extern void my_free_lock(byte *ptr,myf flags); 
extern void init_alloc_root(MEM_ROOT *mem_root, uint block_size,

			    uint pre_alloc_size);

extern gptr alloc_root(MEM_ROOT *mem_root,unsigned int Size);

extern gptr multi_alloc_root(MEM_ROOT *mem_root, ...);

extern void free_root(MEM_ROOT *root, myf MyFLAGS);

extern void set_prealloc_root(MEM_ROOT *root, char *ptr);

extern void reset_root_defaults(MEM_ROOT *mem_root, uint block_size,

libmysqld/Makefile.am

+1 −1
Original line number Diff line number Diff line
@@ -60,7 +60,7 @@ sqlsources = derror.cc field.cc field_conv.cc strfunc.cc filesort.cc \ 
	sql_string.cc sql_table.cc sql_test.cc sql_udf.cc \

	sql_update.cc sql_yacc.cc table.cc thr_malloc.cc time.cc \

	unireg.cc uniques.cc stacktrace.c sql_union.cc hash_filo.cc \

	spatial.cc gstream.cc sql_help.cc tztime.cc protocol_cursor.cc \

	spatial.cc gstream.cc sql_help.cc tztime.cc sql_cursor.cc \

	sp_head.cc sp_pcontext.cc sp.cc sp_cache.cc sp_rcontext.cc \

	parse_file.cc sql_view.cc sql_trigger.cc my_decimal.cc \

	ha_blackhole.cc

mysql-test/r/ctype_ujis.result

+30 −0
Original line number Diff line number Diff line
@@ -2271,3 +2271,33 @@ select c1 from t1 where c1 like 'abcde111%' order by c1; 
c1

abcde111

drop table t1;

DROP TABLE IF EXISTS t1, t2;

DROP PROCEDURE IF EXISTS sp1;

set names ujis;

set character_set_database = ujis;

set character_set_server = ujis;

CREATE TABLE t1(c1 char(2)) default charset = ujis;

CREATE TABLE t2(c2 char(2)) default charset = ujis;

INSERT INTO t1 VALUES(_ujis 0xA4A2);

CREATE PROCEDURE sp1()

BEGIN

DECLARE a CHAR(1);

DECLARE cur1 CURSOR FOR SELECT c1 FROM t1;

OPEN cur1;

FETCH cur1 INTO a;

INSERT INTO t2 VALUES (a);

CLOSE cur1;

END|

CALL sp1();

SELECT c1,c2 FROM t1,t2;

c1	c2

あ	あ

SELECT hex(convert(_latin1 0xA4A2 using ujis)),hex(c2) FROM t1,t2;

hex(convert(_latin1 0xA4A2 using ujis))	hex(c2)

8FA2F0A1F1	A4A2

DROP PROCEDURE sp1;

DROP TABLE t1;

DROP TABLE t2;

set names default;

set character_set_database=default;

set character_set_server=default;

mysql-test/r/sp-big.result

+46 −0
Original line number Diff line number Diff line
@@ -13,3 +13,49 @@ select @value; 
3

drop procedure test.longprocedure;

drop table t1;

create table t1 (f1 char(100) , f2 mediumint , f3 int , f4 real, f5 numeric);

insert into t1 (f1, f2, f3, f4, f5) values

("This is a test case for for Bug#9819", 1, 2, 3.0, 4.598);

Warnings:

Note	1265	Data truncated for column 'f5' at row 1

create table t2 like t1;

select count(*) from t1;

count(*)

256

select count(*) from t2;

count(*)

0

create procedure p1()

begin

declare done integer default 0;

declare vf1 char(100) ;

declare vf2 mediumint;

declare vf3 int ;

declare vf4 real ;

declare vf5 numeric ;

declare cur1 cursor for select f1,f2,f3,f4,f5 from t1;  

declare continue handler for sqlstate '02000' set done = 1; 

open cur1;

while done <> 1 do

fetch cur1 into vf1, vf2, vf3, vf4, vf5;

if not done then

insert into t2 values (vf1, vf2, vf3, vf4, vf5);

end if;

end while;

close cur1;

end|

call p1();

select count(*) from t1;

count(*)

256

select count(*) from t2;

count(*)

256

select f1 from t1 limit 1;

f1

This is a test case for for Bug#9819

select f1 from t2 limit 1;

f1

This is a test case for for Bug#9819

drop procedure p1;

drop table t1, t2;

mysql-test/t/ctype_ujis.test

+42 −0
Original line number Diff line number Diff line
@@ -1151,3 +1151,45 @@ SET collation_connection='ujis_bin'; 
-- source include/ctype_innodb_like.inc



# End of 4.1 tests

--disable_warnings

DROP TABLE IF EXISTS t1, t2;

DROP PROCEDURE IF EXISTS sp1;

--enable_warnings



set names ujis;

set character_set_database = ujis;

set character_set_server = ujis;



CREATE TABLE t1(c1 char(2)) default charset = ujis;

CREATE TABLE t2(c2 char(2)) default charset = ujis;



INSERT INTO t1 VALUES(_ujis 0xA4A2);



DELIMITER |;

CREATE PROCEDURE sp1()

BEGIN

  DECLARE a CHAR(1);

  DECLARE cur1 CURSOR FOR SELECT c1 FROM t1;

  OPEN cur1;

  FETCH cur1 INTO a;

  INSERT INTO t2 VALUES (a);

  CLOSE cur1;

END|

DELIMITER ;|

CALL sp1();



#The data in t1 and t2 should be the same but different

SELECT c1,c2 FROM t1,t2;



#Since the result of hex(convert(_latin1 0xA4A2 using ujis))

#equals to hex(c2), it seems that the value which was inserted 

#by using cursor is interpreted as latin1 character set

SELECT hex(convert(_latin1 0xA4A2 using ujis)),hex(c2) FROM t1,t2;



DROP PROCEDURE sp1;

DROP TABLE t1;

DROP TABLE t2;



set names default;

set character_set_database=default;

set character_set_server=default;