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|
ij(CONNECTION1)> --
-- Licensed to the Apache Software Foundation (ASF) under one or more
-- contributor license agreements. See the NOTICE file distributed with
-- this work for additional information regarding copyright ownership.
-- The ASF licenses this file to You under the Apache License, Version 2.0
-- (the "License"); you may not use this file except in compliance with
-- the License. You may obtain a copy of the License at
--
-- http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software
-- distributed under the License is distributed on an "AS IS" BASIS,
-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-- See the License for the specific language governing permissions and
-- limitations under the License.
--
--------------------------------------------------------------------------------
-- Test multi user lock interaction of ddl.
--------------------------------------------------------------------------------
run resource '/org/apache/derbyTesting/functionTests/tests/store/createTestProcedures.subsql';
ij(CONNECTION1)> --
-- Licensed to the Apache Software Foundation (ASF) under one or more
-- contributor license agreements. See the NOTICE file distributed with
-- this work for additional information regarding copyright ownership.
-- The ASF licenses this file to You under the Apache License, Version 2.0
-- (the "License"); you may not use this file except in compliance with
-- the License. You may obtain a copy of the License at
--
-- http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software
-- distributed under the License is distributed on an "AS IS" BASIS,
-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-- See the License for the specific language governing permissions and
-- limitations under the License.
--
CREATE FUNCTION PADSTRING (DATA VARCHAR(32000), LENGTH INTEGER) RETURNS VARCHAR(32000) EXTERNAL NAME 'org.apache.derbyTesting.functionTests.util.Formatters.padString' LANGUAGE JAVA PARAMETER STYLE JAVA;
0 rows inserted/updated/deleted
ij(CONNECTION1)> CREATE PROCEDURE WAIT_FOR_POST_COMMIT() DYNAMIC RESULT SETS 0 LANGUAGE JAVA EXTERNAL NAME 'org.apache.derbyTesting.functionTests.util.T_Access.waitForPostCommitToFinish' PARAMETER STYLE JAVA;
0 rows inserted/updated/deleted
ij(CONNECTION1)> autocommit off;
ij(CONNECTION1)> connect 'wombat' as deleter;
ij(DELETER)> -- by default, holdability of ResultSet objects created using this Connection object is true. Following will set it to false for this connection.
NoHoldForConnection;
ij(DELETER)> connect 'wombat' as scanner;
ij(SCANNER)> -- by default, holdability of ResultSet objects created using this Connection object is true. Following will set it to false for this connection.
NoHoldForConnection;
ij(SCANNER)> -- set up
set connection scanner;
ij(SCANNER)> set isolation CS;
0 rows inserted/updated/deleted
ij(SCANNER)> run resource '/org/apache/derbyTesting/functionTests/tests/store/LockTableQuery.subsql';
ij(SCANNER)> --
-- Licensed to the Apache Software Foundation (ASF) under one or more
-- contributor license agreements. See the NOTICE file distributed with
-- this work for additional information regarding copyright ownership.
-- The ASF licenses this file to You under the Apache License, Version 2.0
-- (the "License"); you may not use this file except in compliance with
-- the License. You may obtain a copy of the License at
--
-- http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software
-- distributed under the License is distributed on an "AS IS" BASIS,
-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-- See the License for the specific language governing permissions and
-- limitations under the License.
--
create view lock_table as
select
cast(username as char(8)) as username,
cast(t.type as char(15)) as trantype,
cast(l.type as char(8)) as type,
cast(lockcount as char(3)) as cnt,
mode,
cast(tablename as char(12)) as tabname,
cast(lockname as char(10)) as lockname,
state,
status
from
syscs_diag.lock_table l right outer join syscs_diag.transaction_table t
on l.xid = t.xid where l.tableType <> 'S' and t.type='UserTransaction';
0 rows inserted/updated/deleted
ij(SCANNER)> --on l.xid = t.xid where l.tableType <> 'S' or l.tableType is null
-- order by
-- tabname, type desc, mode, cnt, lockname
-- lock table with system catalog locks included.
create view full_lock_table as
select
cast(username as char(8)) as username,
cast(t.type as char(8)) as trantype,
cast(l.type as char(8)) as type,
cast(lockcount as char(3)) as cnt,
mode,
cast(tablename as char(12)) as tabname,
cast(lockname as char(10)) as lockname,
state,
status
from
syscs_diag.lock_table l right outer join syscs_diag.transaction_table t
on l.xid = t.xid where l.tableType <> 'S' ;
0 rows inserted/updated/deleted
ij(SCANNER)> -- lock table with no join.
-- DERBY-6183, removing CAST's to avoid background locks causing
-- data trunction warnings.
create view lock_table2 as
select
xid,
type,
lockcount as cnt,
mode,
tablename as tabname,
lockname,
state
from
syscs_diag.lock_table
where tableType <> 'S' ;
0 rows inserted/updated/deleted
ij(SCANNER)> -- transaction table with no join.
create view tran_table as
select
*
from
syscs_diag.transaction_table;
0 rows inserted/updated/deleted
ij(SCANNER)> autocommit off;
ij(SCANNER)> drop table data;
ERROR 42Y55: 'DROP TABLE' cannot be performed on 'DATA' because it does not exist.
ij(SCANNER)> -- create a table with 2 rows per page.
create table data (keycol int, data varchar(2000)) ;
0 rows inserted/updated/deleted
ij(SCANNER)> insert into data values (0, PADSTRING('0',2000));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (10, PADSTRING('100',2000));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (20, PADSTRING('200',2000));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (30, PADSTRING('300',2000));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (40, PADSTRING('400',2000));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (50, PADSTRING('100',2000));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (60, PADSTRING('200',2000));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (70, PADSTRING('300',2000));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (80, PADSTRING('400',2000));
1 row inserted/updated/deleted
ij(SCANNER)> commit;
ij(SCANNER)> set connection deleter;
ij(DELETER)> set current isolation = cursor stability;
0 rows inserted/updated/deleted
ij(DELETER)> autocommit off;
ij(DELETER)> commit;
ij(DELETER)> --------------------------------------------------------------------------------
-- Test 0: position scanner in the middle of the dataset using group commit
-- in a read commited scan which uses zero duration locks, then have
-- deleter remove all the rows in the table except for the last one,
-- and wait long enough for the post commit job to reclaim the page
-- that the scanner is positioned on. Then do a next on the scanner
-- and verify the scanner goes to the last page.
--------------------------------------------------------------------------------
set connection scanner;
ij(SCANNER)> create table just_to_block_on (a int);
0 rows inserted/updated/deleted
ij(SCANNER)> CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault','2');
0 rows inserted/updated/deleted
ij(SCANNER)> get cursor scan_cursor as
'select keycol from data';
ij(SCANNER)> call SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault', '16');
0 rows inserted/updated/deleted
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
0
ij(SCANNER)> select * from lock_table order by tabname, type desc, mode, cnt, lockname;
USERNAME|TRANTYPE |TYPE |CNT |MODE|TABNAME |LOCKNAME |STATE|STATUS
----------------------------------------------------------------------------------
APP |UserTransaction|TABLE |1 |IS |DATA |Tablelock |GRANT|ACTIVE
WARNING 01004: Data truncation
APP |UserTransaction|TABLE |1 |X |JUST_TO_BLOC|Tablelock |GRANT|ACTIVE
ij(SCANNER)> -- now delete all rows but the last one, space should be reclaimed before
-- the scanner gets a chance to run.
set connection deleter;
ij(DELETER)> select
conglomeratename, isindex,
numallocatedpages, numfreepages, pagesize, estimspacesaving
from
new org.apache.derby.diag.SpaceTable('DATA') t
order by conglomeratename;
CONGLOMERATENAME |ISIND&|NUMALLOCATEDPAGES |NUMFREEPAGES |PAGESIZE |ESTIMSPACESAVING
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
DATA |0 |9 |0 |4096 |0
ij(DELETER)> commit;
ij(DELETER)> delete from data where keycol < 80;
8 rows inserted/updated/deleted
ij(DELETER)> select * from lock_table order by tabname, type desc, mode, cnt, lockname;
USERNAME|TRANTYPE |TYPE |CNT |MODE|TABNAME |LOCKNAME |STATE|STATUS
----------------------------------------------------------------------------------
APP |UserTransaction|TABLE |1 |IS |DATA |Tablelock |GRANT|ACTIVE
WARNING 01004: Data truncation
APP |UserTransaction|TABLE |2 |IX |DATA |Tablelock |GRANT|ACTIVE
APP |UserTransaction|ROW |1 |X |DATA |(1,7) |GRANT|ACTIVE
APP |UserTransaction|ROW |1 |X |DATA |(2,6) |GRANT|ACTIVE
APP |UserTransaction|ROW |1 |X |DATA |(3,6) |GRANT|ACTIVE
APP |UserTransaction|ROW |1 |X |DATA |(4,6) |GRANT|ACTIVE
APP |UserTransaction|ROW |1 |X |DATA |(5,6) |GRANT|ACTIVE
APP |UserTransaction|ROW |1 |X |DATA |(6,6) |GRANT|ACTIVE
APP |UserTransaction|ROW |1 |X |DATA |(7,6) |GRANT|ACTIVE
APP |UserTransaction|ROW |1 |X |DATA |(8,6) |GRANT|ACTIVE
APP |UserTransaction|TABLE |1 |X |JUST_TO_BLOC|Tablelock |GRANT|ACTIVE
ij(DELETER)> commit;
ij(DELETER)> -- give post commit a chance to run, by hanging on a lock.
drop table just_to_block_on;
ERROR 40XL1: A lock could not be obtained within the time requested
ij(DELETER)> commit;
ij(DELETER)> select
conglomeratename, isindex,
numallocatedpages, numfreepages, pagesize, estimspacesaving
from
new org.apache.derby.diag.SpaceTable('DATA') t
order by conglomeratename;
CONGLOMERATENAME |ISIND&|NUMALLOCATEDPAGES |NUMFREEPAGES |PAGESIZE |ESTIMSPACESAVING
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
DATA |0 |2 |7 |4096 |28672
ij(DELETER)> commit;
ij(DELETER)> set connection scanner;
ij(SCANNER)> -- this will return 10, from the group buffer (this looks wierd as 10 is
-- deleted at this point - but that is what you get with read committed).
next scan_cursor;
KEYCOL
-----------
10
ij(SCANNER)> -- this will now go through the code which handles jumping over deleted pages.
next scan_cursor;
KEYCOL
-----------
80
ij(SCANNER)> commit;
ij(SCANNER)> --------------------------------------------------------------------------------
-- cleanup
--------------------------------------------------------------------------------
set connection deleter;
ij(DELETER)> commit;
ij(DELETER)> disconnect;
ij> set connection scanner;
ij(SCANNER)> drop table data;
0 rows inserted/updated/deleted
ij(SCANNER)> drop table just_to_block_on;
0 rows inserted/updated/deleted
ij(SCANNER)> commit;
ij(SCANNER)> disconnect;
ij> --------------------------------------------------------------------------------
-- Test 1: position scanner in the middle of the dataset using group commit
-- in a read commited scan which uses zero duration locks. Now arrange
-- for the row the scan is positioned on to be purged by post commit,
-- but leave a row on the page for scan to reposition to.
--------------------------------------------------------------------------------
---------------
-- setup
---------------
autocommit off;
IJ ERROR: Unable to establish connection
ij> connect 'wombat' as deleter1;
ij(DELETER1)> connect 'wombat' as deleter2;
ij(DELETER2)> connect 'wombat' as scanner;
ij(SCANNER)> connect 'wombat' as lockholder;
ij(LOCKHOLDER)> -- set up
set connection scanner;
ij(SCANNER)> set isolation to read committed;
0 rows inserted/updated/deleted
ij(SCANNER)> autocommit off;
ij(SCANNER)> drop table data;
ERROR 42Y55: 'DROP TABLE' cannot be performed on 'DATA' because it does not exist.
ij(SCANNER)> -- create a table with 4 rows per page.
create table data (keycol int, data varchar(900));
0 rows inserted/updated/deleted
ij(SCANNER)> insert into data values (0, PADSTRING('0',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (10, PADSTRING('100',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (20, PADSTRING('200',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (30, PADSTRING('300',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (40, PADSTRING('400',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (50, PADSTRING('100',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (60, PADSTRING('200',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (70, PADSTRING('300',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (80, PADSTRING('400',900));
1 row inserted/updated/deleted
ij(SCANNER)> create unique index idx on data (keycol);
0 rows inserted/updated/deleted
ij(SCANNER)> commit;
ij(SCANNER)> set connection deleter1;
ij(DELETER1)> set isolation read committed;
0 rows inserted/updated/deleted
ij(DELETER1)> autocommit off;
ij(DELETER1)> commit;
ij(DELETER1)> set connection deleter2;
ij(DELETER2)> set isolation READ COMMITTED;
0 rows inserted/updated/deleted
ij(DELETER2)> autocommit off;
ij(DELETER2)> commit;
ij(DELETER2)> set connection lockholder;
ij(LOCKHOLDER)> set CURRENT isolation TO CS;
0 rows inserted/updated/deleted
ij(LOCKHOLDER)> autocommit off;
ij(LOCKHOLDER)> commit;
ij(LOCKHOLDER)> --------------
-- run the test
--------------
set connection lockholder;
ij(LOCKHOLDER)> create table just_to_block_on (a int);
0 rows inserted/updated/deleted
ij(LOCKHOLDER)> set connection scanner;
ij(SCANNER)> CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault','2');
0 rows inserted/updated/deleted
ij(SCANNER)> get cursor scan_cursor as
'select keycol from data';
ij(SCANNER)> call SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault', '16');
0 rows inserted/updated/deleted
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
0
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
10
ij(SCANNER)> -- scan is now positioned on row (10, 100), as it group fetched 2 rows.
-- in deleter1 thread delete the last row on the page, but don't commit.
-- in the other deleter thread delete the rest of the rows on the page and
-- commit it, which will result in a post commit to try and reclaim all the
-- rows on the page, but it won't be able to reclaim the one that has not
-- been committed by deleter1.
-- delete in this transaction keycol (30, 300).
set connection deleter1;
ij(DELETER1)> delete from data where keycol = 30;
1 row inserted/updated/deleted
ij(DELETER1)> -- delete in this transaction the rest of rows on the page.
set connection deleter2;
ij(DELETER2)> delete from data where keycol = 0;
1 row inserted/updated/deleted
ij(DELETER2)> delete from data where keycol = 10;
1 row inserted/updated/deleted
ij(DELETER2)> delete from data where keycol = 20;
1 row inserted/updated/deleted
ij(DELETER2)> commit;
ij(DELETER2)> -- block deleter threads on a lock to give post commit a chance to run.
set connection deleter2;
ij(DELETER2)> select * from just_to_block_on;
ERROR 40XL1: A lock could not be obtained within the time requested
ij(DELETER2)> set connection deleter1;
ij(DELETER1)> select * from just_to_block_on;
ERROR 40XL1: A lock could not be obtained within the time requested
ij(DELETER1)> -- now assume post commit has run, roll back deleter1 so that one non-deleted
-- row remains on the page.
set connection deleter1;
ij(DELETER1)> rollback;
ij(DELETER1)> -- the scanner gets a chance to run.
set connection scanner;
ij(SCANNER)> -- now at this point the scanner will resume and find the row it is positioned
-- on has been purged, and it will reposition automatically to (30, 300) on
-- the same page.
next scan_cursor;
KEYCOL
-----------
30
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
40
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
50
ij(SCANNER)> commit;
ij(SCANNER)> select * from data;
KEYCOL |DATA
--------------------------------------------------------------------------------------------------------------------------------------------
30 |300 &
40 |400 &
50 |100 &
60 |200 &
70 |300 &
80 |400 &
ij(SCANNER)> commit;
ij(SCANNER)> --------------------------------------------------------------------------------
-- cleanup
--------------------------------------------------------------------------------
set connection scanner;
ij(SCANNER)> disconnect;
ij> set connection deleter1;
ij(DELETER1)> disconnect;
ij> set connection deleter2;
ij(DELETER2)> disconnect;
ij> set connection lockholder;
ij(LOCKHOLDER)> disconnect;
ij> --------------------------------------------------------------------------------
-- Test 2: position scanner in the middle of the dataset using group commit
-- in a read commited scan which uses zero duration locks. Now arrange
-- for the row the scan is positioned on to be purged by post commit,
-- but leave a row on the page for scan to reposition to, as did Test 1.
-- This time make the row left on the page be deleted, so when the
-- scan repositions, it should jump over the deleted row.
--------------------------------------------------------------------------------
---------------
-- setup
---------------
connect 'wombat' as deleter1;
ij(DELETER1)> connect 'wombat' as deleter2;
ij(DELETER2)> connect 'wombat' as scanner;
ij(SCANNER)> connect 'wombat' as lockholder;
ij(LOCKHOLDER)> -- set up
set connection scanner;
ij(SCANNER)> set isolation read committed;
0 rows inserted/updated/deleted
ij(SCANNER)> autocommit off;
ij(SCANNER)> drop table data;
0 rows inserted/updated/deleted
ij(SCANNER)> -- create a table with 4 rows per page.
create table data (keycol int, data varchar(900)) ;
0 rows inserted/updated/deleted
ij(SCANNER)> insert into data values (0, PADSTRING('0',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (10, PADSTRING('100',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (20, PADSTRING('200',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (30, PADSTRING('300',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (40, PADSTRING('400',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (50, PADSTRING('100',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (60, PADSTRING('200',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (70, PADSTRING('300',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (80, PADSTRING('400',900));
1 row inserted/updated/deleted
ij(SCANNER)> create unique index idx on data (keycol);
0 rows inserted/updated/deleted
ij(SCANNER)> commit;
ij(SCANNER)> set connection deleter1;
ij(DELETER1)> set isolation read committed;
0 rows inserted/updated/deleted
ij(DELETER1)> autocommit off;
ij(DELETER1)> commit;
ij(DELETER1)> set connection deleter2;
ij(DELETER2)> set isolation read committed;
0 rows inserted/updated/deleted
ij(DELETER2)> autocommit off;
ij(DELETER2)> commit;
ij(DELETER2)> set connection lockholder;
ij(LOCKHOLDER)> set isolation read committed;
0 rows inserted/updated/deleted
ij(LOCKHOLDER)> autocommit off;
ij(LOCKHOLDER)> commit;
ij(LOCKHOLDER)> --------------
-- run the test
--------------
set connection lockholder;
ij(LOCKHOLDER)> create table just_to_block_on (a int);
0 rows inserted/updated/deleted
ij(LOCKHOLDER)> set connection scanner;
ij(SCANNER)> CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault','2');
0 rows inserted/updated/deleted
ij(SCANNER)> get cursor scan_cursor as
'select keycol from data';
ij(SCANNER)> call SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault', '16');
0 rows inserted/updated/deleted
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
0
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
10
ij(SCANNER)> -- scan is now positioned on row (10, 100), as it group fetched 2 rows.
-- In the deleter1 thread delete the last row on the page, but don't commit.
-- in the other deleter thread delete the rest of the rows on the page and
-- commit it, which will result in a post commit to try and reclaim all the
-- rows on the page, but it won't be able to reclaim the one that has not
-- been committed by deleter1.
-- delete in this transaction keycol (30, 300).
set connection deleter1;
ij(DELETER1)> delete from data where keycol = 30;
1 row inserted/updated/deleted
ij(DELETER1)> -- delete in this transaction the rest of rows on the page.
set connection deleter2;
ij(DELETER2)> delete from data where keycol = 0;
1 row inserted/updated/deleted
ij(DELETER2)> delete from data where keycol = 10;
1 row inserted/updated/deleted
ij(DELETER2)> delete from data where keycol = 20;
1 row inserted/updated/deleted
ij(DELETER2)> commit;
ij(DELETER2)> -- block deleter threads on a lock to give post commit a chance to run.
set connection deleter2;
ij(DELETER2)> select * from just_to_block_on;
ERROR 40XL1: A lock could not be obtained within the time requested
ij(DELETER2)> -- now assume post commit has run, commit deleter1 so that one deleted
-- row remains on the page after the positioned row.
set connection deleter1;
ij(DELETER1)> commit;
ij(DELETER1)> -- the scanner gets a chance to run.
set connection scanner;
ij(SCANNER)> -- now at this point the scanner will resume and find the row it is positioned
-- on has been purged, the only rows following it to be deleted and it will
-- reposition automatically to (40, 400) on the next page.
next scan_cursor;
KEYCOL
-----------
40
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
50
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
60
ij(SCANNER)> commit;
ij(SCANNER)> select * from data;
KEYCOL |DATA
--------------------------------------------------------------------------------------------------------------------------------------------
40 |400 &
50 |100 &
60 |200 &
70 |300 &
80 |400 &
ij(SCANNER)> commit;
ij(SCANNER)> --------------------------------------------------------------------------------
-- cleanup
--------------------------------------------------------------------------------
set connection scanner;
ij(SCANNER)> disconnect;
ij> set connection deleter1;
ij(DELETER1)> disconnect;
ij> set connection deleter2;
ij(DELETER2)> disconnect;
ij> set connection deleter2;
IJ ERROR: No connection exists with the name DELETER2
ij> disconnect;
IJ ERROR: Unable to establish connection
ij> set connection lockholder;
ij(LOCKHOLDER)> disconnect;
ij> --------------------------------------------------------------------------------
-- Test 3: position scanner in the middle of the dataset using group commit
-- in a read commited scan which uses zero duration locks. Now arrange
-- for the row the scan is positioned on, and all rows following it on
-- the page to be purged by post commit, but leave at least one row on
-- the page so that the page is not removed. The reposition code will
-- position on the page, find the row has disappeared, ask for the
-- "next" row on the page, find that no such row exists on the page,
-- and finally move to the next page.
--------------------------------------------------------------------------------
---------------
-- setup
---------------
connect 'wombat' as deleter1;
ij(DELETER1)> connect 'wombat' as deleter2;
ij(DELETER2)> connect 'wombat' as scanner;
ij(SCANNER)> connect 'wombat' as lockholder;
ij(LOCKHOLDER)> -- set up
set connection scanner;
ij(SCANNER)> set isolation read committed;
0 rows inserted/updated/deleted
ij(SCANNER)> autocommit off;
ij(SCANNER)> drop table data;
0 rows inserted/updated/deleted
ij(SCANNER)> -- create a table with 4 rows per page.
create table data (keycol int, data varchar(900)) ;
0 rows inserted/updated/deleted
ij(SCANNER)> insert into data values (0, PADSTRING('0',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (10, PADSTRING('100',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (20, PADSTRING('200',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (30, PADSTRING('300',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (40, PADSTRING('400',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (50, PADSTRING('100',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (60, PADSTRING('200',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (70, PADSTRING('300',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (80, PADSTRING('400',900));
1 row inserted/updated/deleted
ij(SCANNER)> create unique index idx on data (keycol);
0 rows inserted/updated/deleted
ij(SCANNER)> commit;
ij(SCANNER)> set connection deleter1;
ij(DELETER1)> set isolation read committed;
0 rows inserted/updated/deleted
ij(DELETER1)> autocommit off;
ij(DELETER1)> commit;
ij(DELETER1)> set connection deleter2;
ij(DELETER2)> set isolation read committed;
0 rows inserted/updated/deleted
ij(DELETER2)> autocommit off;
ij(DELETER2)> commit;
ij(DELETER2)> set connection lockholder;
ij(LOCKHOLDER)> set isolation read committed;
0 rows inserted/updated/deleted
ij(LOCKHOLDER)> autocommit off;
ij(LOCKHOLDER)> commit;
ij(LOCKHOLDER)> --------------
-- run the test
--------------
set connection lockholder;
ij(LOCKHOLDER)> create table just_to_block_on (a int);
0 rows inserted/updated/deleted
ij(LOCKHOLDER)> set connection scanner;
ij(SCANNER)> CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault','2');
0 rows inserted/updated/deleted
ij(SCANNER)> get cursor scan_cursor as
'select keycol from data';
ij(SCANNER)> call SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault', '16');
0 rows inserted/updated/deleted
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
0
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
10
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
20
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
30
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
40
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
50
ij(SCANNER)> -- scan is now positioned on row (50, 500), as it group fetched in 2 row chunks.
-- In the deleter1 thread delete the 1st row on the page, but don't commit:
-- (40, 400).
-- In the deleter2 thread delete the current row and the rows following on the
-- page, and commit: (50, 500), (60, 600), (70, 700). This will result in
-- the code seeing a page with all rows deleted and then queue a post commit on
-- the page which will purge 50, 60, and 70, but it won't be able to reclaim
-- the one that has not been committed by deleter1.
-- delete in this transaction keycol (30, 300).
set connection deleter1;
ij(DELETER1)> delete from data where keycol = 40;
1 row inserted/updated/deleted
ij(DELETER1)> -- delete in this transaction the rest of rows on the page.
set connection deleter2;
ij(DELETER2)> delete from data where keycol = 50;
1 row inserted/updated/deleted
ij(DELETER2)> delete from data where keycol = 60;
1 row inserted/updated/deleted
ij(DELETER2)> delete from data where keycol = 70;
1 row inserted/updated/deleted
ij(DELETER2)> commit;
ij(DELETER2)> -- block deleter threads on a lock to give post commit a chance to run.
set connection deleter2;
ij(DELETER2)> select * from just_to_block_on;
ERROR 40XL1: A lock could not be obtained within the time requested
ij(DELETER2)> -- now assume post commit has run, commit deleter1 so that one deleted
-- row remains on the page after the positioned row.
set connection deleter1;
ij(DELETER1)> commit;
ij(DELETER1)> -- the scanner gets a chance to run.
set connection scanner;
ij(SCANNER)> -- now at this point the scanner will resume and find the row it is positioned
-- on has been purged, the only rows following it to be deleted and it will
-- reposition automatically to (80, 800) on the next page.
next scan_cursor;
KEYCOL
-----------
80
ij(SCANNER)> next scan_cursor;
No current row
ij(SCANNER)> commit;
ij(SCANNER)> select * from data;
KEYCOL |DATA
--------------------------------------------------------------------------------------------------------------------------------------------
0 |0 &
10 |100 &
20 |200 &
30 |300 &
80 |400 &
ij(SCANNER)> commit;
ij(SCANNER)> --------------------------------------------------------------------------------
-- cleanup
--------------------------------------------------------------------------------
set connection scanner;
ij(SCANNER)> disconnect;
ij> set connection deleter1;
ij(DELETER1)> disconnect;
ij> set connection deleter2;
ij(DELETER2)> disconnect;
ij> set connection deleter2;
IJ ERROR: No connection exists with the name DELETER2
ij> disconnect;
IJ ERROR: Unable to establish connection
ij> set connection lockholder;
ij(LOCKHOLDER)> disconnect;
ij> --------------------------------------------------------------------------------
-- Test 4: position scanner in the middle of the dataset using group commit
-- in a read commited scan which uses zero duration locks. Now arrange
-- for all rows in the table to be purged. The reposition code will
-- attempt to position on the "next" page, and find no more pages.
--------------------------------------------------------------------------------
---------------
-- setup
---------------
connect 'wombat' as deleter1;
ij(DELETER1)> connect 'wombat' as deleter2;
ij(DELETER2)> connect 'wombat' as scanner;
ij(SCANNER)> connect 'wombat' as lockholder;
ij(LOCKHOLDER)> -- set up
set connection scanner;
ij(SCANNER)> set isolation read committed;
0 rows inserted/updated/deleted
ij(SCANNER)> autocommit off;
ij(SCANNER)> drop table data;
0 rows inserted/updated/deleted
ij(SCANNER)> -- create a table with 4 rows per page.
create table data (keycol int, data varchar(900)) ;
0 rows inserted/updated/deleted
ij(SCANNER)> insert into data values (0, PADSTRING('0',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (10, PADSTRING('100',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (20, PADSTRING('200',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (30, PADSTRING('300',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (40, PADSTRING('400',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (50, PADSTRING('100',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (60, PADSTRING('200',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (70, PADSTRING('300',900));
1 row inserted/updated/deleted
ij(SCANNER)> insert into data values (80, PADSTRING('400',900));
1 row inserted/updated/deleted
ij(SCANNER)> create unique index idx on data (keycol);
0 rows inserted/updated/deleted
ij(SCANNER)> commit;
ij(SCANNER)> set connection deleter1;
ij(DELETER1)> set isolation read committed;
0 rows inserted/updated/deleted
ij(DELETER1)> autocommit off;
ij(DELETER1)> commit;
ij(DELETER1)> set connection deleter2;
ij(DELETER2)> set isolation read committed;
0 rows inserted/updated/deleted
ij(DELETER2)> autocommit off;
ij(DELETER2)> commit;
ij(DELETER2)> set connection lockholder;
ij(LOCKHOLDER)> set isolation read committed;
0 rows inserted/updated/deleted
ij(LOCKHOLDER)> autocommit off;
ij(LOCKHOLDER)> commit;
ij(LOCKHOLDER)> --------------
-- run the test
--------------
set connection lockholder;
ij(LOCKHOLDER)> create table just_to_block_on (a int);
0 rows inserted/updated/deleted
ij(LOCKHOLDER)> set connection scanner;
ij(SCANNER)> CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault','2');
0 rows inserted/updated/deleted
ij(SCANNER)> get cursor scan_cursor as
'select keycol from data';
ij(SCANNER)> call SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault', '16');
0 rows inserted/updated/deleted
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
0
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
10
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
20
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
30
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
40
ij(SCANNER)> next scan_cursor;
KEYCOL
-----------
50
ij(SCANNER)> -- scan is now positioned on row (50, 500), as it group fetched in 2 row chunks.
-- In the deleter1 thread delete all the rows, allowing all rows/pages to be
-- reclaimed.
-- delete in this transaction all rows.
set connection deleter1;
ij(DELETER1)> delete from data where keycol >= 0 ;
9 rows inserted/updated/deleted
ij(DELETER1)> commit;
ij(DELETER1)> -- block deleter threads on a lock to give post commit a chance to run.
set connection deleter2;
ij(DELETER2)> select * from just_to_block_on;
ERROR 40XL1: A lock could not be obtained within the time requested
ij(DELETER2)> -- now assume post commit has run, commit deleter1 so that one deleted
-- row remains on the page after the positioned row.
commit;
ij(DELETER2)> -- the scanner gets a chance to run.
set connection scanner;
ij(SCANNER)> -- now at this point the scanner will resume and find the row it is positioned
-- on has been purged, and no rows or pages remaining in the table.
next scan_cursor;
No current row
ij(SCANNER)> next scan_cursor;
No current row
ij(SCANNER)> commit;
ij(SCANNER)> select * from data;
KEYCOL |DATA
--------------------------------------------------------------------------------------------------------------------------------------------
ij(SCANNER)> commit;
ij(SCANNER)> --------------------------------------------------------------------------------
-- cleanup
--------------------------------------------------------------------------------
set connection scanner;
ij(SCANNER)> disconnect;
ij> set connection deleter1;
ij(DELETER1)> disconnect;
ij> set connection deleter2;
ij(DELETER2)> disconnect;
ij> set connection deleter2;
IJ ERROR: No connection exists with the name DELETER2
ij> disconnect;
IJ ERROR: Unable to establish connection
ij> set connection lockholder;
ij(LOCKHOLDER)> disconnect;
ij> exit;
|
