rlliso3multi.sql

来自「derby database source code.good for you.」· SQL 代码 · 共 496 行 · 第 1/2 页

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-- Test multi user lock interaction under isolation level 3.  default isolation
-- level has been set as a property to serializable.
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-- Test 0: verify isolation level by seeing if a read lock is released or not.
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connect 'wombat' as scanner;
set isolation to rr;
-- by default, holdability of ResultSet objects created using this Connection object is true. Following will set it to false for this connection.
NoHoldForConnection;

connect 'wombat' as writer;
set isolation to rr;
-- by default, holdability of ResultSet objects created using this Connection object is true. Following will set it to false for this connection.
NoHoldForConnection;

run resource 'createTestProcedures.subsql';
call SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.storage.pageSize', '4096');

-- set up
set connection scanner;
autocommit off;
create table test_0 (a int);
insert into test_0 values (1);
commit;

set connection writer;
autocommit off;

-- scanner should hold read lock on table until end of transaction.
set connection scanner;
select * from test_0;

-- writer should get a lock timeout.
set connection writer;
insert into test_0 values (2);

-- scanner should only see the original row.
set connection scanner;
select * from test_0;
commit;
select * from test_0;

-- cleanup
set connection scanner;
drop table test_0;
commit;
disconnect;
set connection writer;
disconnect;


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-- Test 1: make sure a leaf root growing get's the right lock.
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-- Test setup - create a 1 page btre, with the page ready to split.
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connect 'wombat' as scanner;
set isolation to rr;
-- by default, holdability of ResultSet objects created using this Connection object is true. Following will set it to false for this connection.
NoHoldForConnection;

connect 'wombat' as rootgrower;
set isolation to rr;
-- by default, holdability of ResultSet objects created using this Connection object is true. Following will set it to false for this connection.
NoHoldForConnection;

set connection scanner;
autocommit off;
create table a (a varchar(1000), b varchar(1000)) ;
insert into a values (PADSTRING('a',1000), PADSTRING('a',1000));
insert into a values (PADSTRING('b',1000), PADSTRING('b',1000));
insert into a values (PADSTRING('c',1000), PADSTRING('c',1000));
create index a_idx on a (a) ;;
commit;

set connection rootgrower;
autocommit off;
commit;


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-- Set up scanner to be doing a row locked covered scan on the index.
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set connection scanner;
autocommit off;
CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault','1');
get cursor scan_cursor as 
    'select a from a where a >= PADSTRING(''a'',1000) and a < PADSTRING(''c'',1000) ';
call SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.language.bulkFetchDefault', '16');
next scan_cursor;

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-- This should block on the scan lock held by the scanner on the first page.
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set connection rootgrower;
autocommit off;
insert into a values (PADSTRING('d',1000), PADSTRING('d',1000));

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-- The scan should continue unaffected.
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set connection scanner;
next scan_cursor;
next scan_cursor;

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-- This insert will block on the previous key lock of the scanner.
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set connection rootgrower;
insert into a values (PADSTRING('ab',1000), PADSTRING('ab',1000));

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-- Now the grow root should be allowed (note that cursor scan has locks
-- on the leaf page being grown - just not the scan lock).
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set connection rootgrower;
insert into a values (PADSTRING('d',1000), PADSTRING('d',1000));

select a from a;


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-- cleanup.
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set connection rootgrower;
commit;
disconnect;
set connection scanner;
commit;
drop table a;
commit;
disconnect;


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-- Test 2: make sure previous key locks are gotten correctly.
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connect 'wombat' as client_1;
set isolation to rr;
-- by default, holdability of ResultSet objects created using this Connection object is true. Following will set it to false for this connection.
NoHoldForConnection;

connect 'wombat' as client_2;
set isolation to rr;
-- by default, holdability of ResultSet objects created using this Connection object is true. Following will set it to false for this connection.
NoHoldForConnection;

set connection client_1;
autocommit off;
create table a (a varchar(1000), b varchar(1000)) ;
create index a_idx on a (a) ;
commit;
insert into a values (PADSTRING('b',1000), PADSTRING('b',1000));

set connection client_2;
autocommit off;
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-- the following will not cause a time out, as the previous
-- key insert lock will not conflict with other insert locks, only other
-- select locks, or non insert update locks.

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insert into a values (PADSTRING('c',1000), PADSTRING('c',1000));

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-- the following should NOT cause a time out
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insert into a values (PADSTRING('a',1000), PADSTRING('a',1000));

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-- cleanup.
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set connection client_1;
commit;
set connection client_2;
commit;
drop table a;
commit;

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-- Test 3: make sure an exact key insert into unique key index blocks.
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set connection client_1;
autocommit off;
create table a (a varchar(1000), b varchar(1000));
create unique index a_idx on a (a) ;
commit;
insert into a values (PADSTRING('b',1000), PADSTRING('b',1000));

set connection client_2;
autocommit off;
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-- the following should cause a time out, as the previous
-- key lock will conflict with client_1's lock on 'b'
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insert into a values (PADSTRING('b',1000), PADSTRING('b',1000));

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-- Test 4: make sure that row lock wait in a heap scan works
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set connection client_1;
autocommit off;
create table test_4 (a int, b varchar(1000), c varchar(1000)) ;
commit;
set connection client_2;
autocommit off;
commit;

-- client_1 will get a single row lock in the heap.
set connection client_1;
insert into test_4 values (1, PADSTRING('a',1000), PADSTRING('b',1000)); 

-- client_2 scans table, blocking on a row lock on the client_1 insert row, 
-- will get timout message.
set connection client_2;
select * from test_4;

-- release the insert lock.
set connection client_1;
commit;

-- reader should be able to see row now.
set connection client_2;
select * from test_4;
commit;

-- cleanup
set connection client_1;
drop table test_4;
commit;

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-- Test 5: make sure a that a group fetch through a secondary index correctly
--         handles the previous to first key locking.  In serializable the
--         scanner should hold the previous to first key lock until end of 
--         transaction, thus blocking the attempted insert to the range.
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connect 'wombat' as scanner;
set isolation to rr;
-- by default, holdability of ResultSet objects created using this Connection object is true. Following will set it to false for this connection.
NoHoldForConnection;