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--
-- 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.
--
-- Basic single user testing of read locks on select "set" queries on indexes.
--
-- This ".subsql" test is
-- meant to be run from another test such that it gets run under multiple
-- isolation levels. This is important as they behave
-- differently, depending on isolation levels.
--
-- assume's caller has already done: run 'LockTableQuery.subsql'; to get
-- easy access to the lock VTI.
-- TEST 0: btree scan
-- TEST 1: btree scan, (scan table with some deleted rows)
-- TEST 2: btree scan, (scan with "<" qualifier)
-- TEST 3: btree scan, (scan with equals qualifier)
-- TEST 4: btree scan, (equals qualifier, no rows return)
autocommit off;
--------------------------------------------------------------------------------
-- Assumes that calling routine has set up the following simple dataset,
-- a heap, and index with following initial values:
-- create table a (a int, b int, c somesortofchar, [index_pad]);
-- create index a_idx on a (a) or a_idx on a (a, index_pad);
--
-- 1, 10, 'one'
-- 2, 20, 'two'
-- 3, 30, 'three'
-- 4, 40, 'four'
-- 5, 50, 'five'
-- 6, 60, 'six'
-- 7, 70, 'seven'
--------------------------------------------------------------------------------
select * from a;
commit;
--------------------------------------------------------------------------------
-- TEST 0: btree scan
-- Test full scan.
-- ALL MODES - TABLE IS, "scan page lockname of form (pageno, 1)
-- SERIALIZABLE - row S locks as it visits each row, row/table lock
-- held until end xact. Also holds one previous key lock.
-- REPEATABLE READ - row S locks as it visits each row, row/table locks held
-- until end of transaction.
-- READ COMMITTED - instantaneous S locks requested on each row. No locks
-- held after query finishes.
-- READ UNCOMMITTED - no row locks. No locks held after query finishes.
--------------------------------------------------------------------------------
select a from a;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
--------------------------------------------------------------------------------
-- TEST 1: btree scan, (scan table with some deleted rows)
-- Test full scan on a data set with some deleted rows (the "even" ones).
-- ALL MODES - TABLE IS, "scan page lockname of form (pageno, 1)
-- SERIALIZABLE - row S locks as it visits each row, row/table lock
-- held until end xact. Also holds one previous key lock.
-- REPEATABLE READ - row S locks as it visits each row, row/table locks held
-- until end of transaction.
-- READ COMMITTED - instantaneous S locks requested on each row. No locks
-- held after query finishes.
-- READ UNCOMMITTED - no row locks. No locks held after query finishes.
--
-- After the delete the base table should look like:
-- 1, 10, 'one'
-- 3, 30, 'three'
-- 5, 50, 'five'
-- 7, 70, 'seven'
--------------------------------------------------------------------------------
delete from a where a = 2 or a = 4 or a = 6;
commit;
-- The above delete and commit can allow post commit processing to run before
-- the subsequent select is run, most likely if this run is on a table where
-- there is one row per page. To get reproducible results from the subsequent
-- lock calls, wait for post commit to finish before running the select.
-- Without this wait "extra" locks sometimes might show up - these are locks
-- on the committed deleted rows which have not been cleaned yet depending
-- on timing.
CALL WAIT_FOR_POST_COMMIT();
select a from a;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
--------------------------------------------------------------------------------
-- TEST 2: btree scan, (scan with "<" qualifier)
-- Test "less than" qualified scan on a data set.
-- ALL MODES - TABLE IS, "scan page lockname of form (pageno, 1)
-- SERIALIZABLE - row S locks as it visits each row, row/table lock
-- held until end xact. Also holds one previous key lock.
-- REPEATABLE READ - row S locks as it visits each row, row/table locks held
-- until end of transaction.
-- READ COMMITTED - instantaneous S locks requested on each row. No locks
-- held after query finishes.
-- READ UNCOMMITTED - no row locks. No locks held after query finishes.
--
-- At this point the base table should look like:
-- 1, 10, 'one'
-- 3, 30, 'three'
-- 5, 50, 'five'
-- 7, 70, 'seven'
--------------------------------------------------------------------------------
select a from a where a < 3;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
--------------------------------------------------------------------------------
-- TEST 3: btree scan, (scan with equals qualifier)
-- Test "equals" qualified cursor scan on a data set.
-- ALL MODES - TABLE IS, "scan page lockname of form (pageno, 1)
-- SERIALIZABLE - row S locks as it visits each row, row/table lock
-- held until end xact. Also holds one previous key lock.
-- REPEATABLE READ - row S locks as it visits each row, row/table locks held
-- until end of transaction.
-- READ COMMITTED - instantaneous S locks requested on each row. No locks
-- held after query finishes.
-- READ UNCOMMITTED - no row locks. No locks held after query finishes.
--
-- At this point the base table should look like:
-- 1, 10, 'one'
-- 3, 30, 'three'
-- 5, 50, 'five'
-- 7, 70, 'seven'
--------------------------------------------------------------------------------
select a from a where a = 5;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
--------------------------------------------------------------------------------
-- TEST 4: btree scan, (equals qualifier, no rows return)
-- Test "equals" qualified scan on a data set, no rows returned.
-- ALL MODES - TABLE IS, "scan page lockname of form (pageno, 1)
-- SERIALIZABLE - row S locks as it visits each row, row/table lock
-- held until end xact. Also holds one previous key lock.
-- REPEATABLE READ - row S locks as it visits each row, row/table locks held
-- until end of transaction.
-- READ COMMITTED - instantaneous S locks requested on each row. No locks
-- held after query finishes.
-- READ UNCOMMITTED - no row locks. No locks held after query finishes.
--
-- At this point the base table should look like:
-- 1, 10, 'one'
-- 3, 30, 'three'
-- 5, 50, 'five'
-- 7, 70, 'seven'
--------------------------------------------------------------------------------
-- no rows expected to qualify
select a from a where a = 42;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
select * from lock_table order by tabname, type desc, mode, cnt, lockname;
commit;
drop table a;
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