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#
# Test how we handle locking in various cases when
# we read data from MyISAM tables.
#
# In this test we mostly check that the SQL-layer correctly
# determines the type of thr_lock.c lock for a table being
# read.
# I.e. that it disallows concurrent inserts when the statement
# is going to be written to the binary log and therefore
# should be serialized, and allows concurrent inserts when
# such serialization is not necessary (e.g. when 
# the statement is not written to binary log).
#
# Force concurrent inserts to be performed even if the table
# has gaps. This allows to simplify clean up in scripts
# used below (instead of backing up table being inserted
# into and then restoring it from backup at the end of the
# script we can simply delete rows which were inserted).
set @old_concurrent_insert= @@global.concurrent_insert;
set @@global.concurrent_insert= 2;
select @@global.concurrent_insert;
@@global.concurrent_insert
ALWAYS
# Prepare playground by creating tables, views,
# routines and triggers used in tests.
drop table if exists t0, t1, t2, t3, t4, t5;
drop view if exists v1, v2;
drop procedure if exists p1;
drop procedure if exists p2;
drop function if exists f1;
drop function if exists f2;
drop function if exists f3;
drop function if exists f4;
drop function if exists f5;
drop function if exists f6;
drop function if exists f7;
drop function if exists f8;
drop function if exists f9;
drop function if exists f10;
drop function if exists f11;
drop function if exists f12;
drop function if exists f13;
drop function if exists f14;
drop function if exists f15;
create table t1 (i int primary key);
insert into t1 values (1), (2), (3), (4), (5);
create table t2 (j int primary key);
insert into t2 values (1), (2), (3), (4), (5);
create table t3 (k int primary key);
insert into t3 values (1), (2), (3);
create table t4 (l int primary key);
insert into t4 values (1);
create table t5 (l int primary key);
insert into t5 values (1);
create view v1 as select i from t1;
create view v2 as select j from t2 where j in (select i from t1);
create procedure p1(k int) insert into t2 values (k);
create function f1() returns int
begin
declare j int;
select i from t1 where i = 1 into j;
return j;
end|
create function f2() returns int
begin
declare k int;
select i from t1 where i = 1 into k;
insert into t2 values (k + 5);
return 0;
end|
create function f3() returns int
begin
return (select i from t1 where i = 3);
end|
create function f4() returns int
begin
if (select i from t1 where i = 3) then
return 1;
else
return 0;
end if;
end|
create function f5() returns int
begin
insert into t2 values ((select i from t1 where i = 1) + 5);
return 0;
end|
create function f6() returns int
begin
declare k int;
select i from v1 where i = 1 into k;
return k;
end|
create function f7() returns int
begin
declare k int;
select j from v2 where j = 1 into k;
return k;
end|
create function f8() returns int
begin
declare k int;
select i from v1 where i = 1 into k;
insert into t2 values (k+5);
return k;
end|
create function f9() returns int
begin
update v2 set j=j+10 where j=1;
return 1;
end|
create function f10() returns int
begin
return f1();
end|
create function f11() returns int
begin
declare k int;
set k= f1();
insert into t2 values (k+5);
return k;
end|
create function f12(p int) returns int
begin
insert into t2 values (p);
return p;
end|
create function f13(p int) returns int
begin
return p;
end|
create procedure p2(inout p int)
begin
select i from t1 where i = 1 into p;
end|
create function f14() returns int
begin
declare k int;
call p2(k);
insert into t2 values (k+5);
return k;
end|
create function f15() returns int
begin
declare k int;
call p2(k);
return k;
end|
create trigger t4_bi before insert on t4 for each row
begin
declare k int;
select i from t1 where i=1 into k;
set new.l= k+1;
end|
create trigger t4_bu before update on t4 for each row
begin
if (select i from t1 where i=1) then
set new.l= 2;
end if;
end|
create trigger t4_bd before delete on t4 for each row
begin
if !(select i from v1 where i=1) then
signal sqlstate '45000';
end if;
end|
create trigger t5_bi before insert on t5 for each row
begin
set new.l= f1()+1;
end|
create trigger t5_bu before update on t5 for each row
begin
declare j int;
call p2(j);
set new.l= j + 1;
end|
#
# Set common variables to be used by the scripts
# called below.
#
# Switch to connection 'con1'.
# Cache all functions used in the tests below so statements
# calling them won't need to open and lock mysql.proc table
# and we can assume that each statement locks its tables
# once during its execution.
show create procedure p1;
show create procedure p2;
show create function f1;
show create function f2;
show create function f3;
show create function f4;
show create function f5;
show create function f6;
show create function f7;
show create function f8;
show create function f9;
show create function f10;
show create function f11;
show create function f12;
show create function f13;
show create function f14;
show create function f15;
# Switch back to connection 'default'.
#
# 1. Statements that read tables and do not use subqueries.
#
#
# 1.1 Simple SELECT statement.
#
# No locks are necessary as this statement won't be written
# to the binary log and thanks to how MyISAM works SELECT
# will see version of the table prior to concurrent insert.
Success: 'select * from t1' allows concurrent inserts into 't1'.
#
# 1.2 Multi-UPDATE statement.
#
# Has to take shared locks on rows in the table being read as this
# statement will be written to the binary log and therefore should
# be serialized with concurrent statements.
Success: 'update t2, t1 set j= j - 1 where i = j' doesn't allow concurrent inserts into 't1'.
#
# 1.3 Multi-DELETE statement.
#
# The above is true for this statement as well.
Success: 'delete t2 from t1, t2 where i = j' doesn't allow concurrent inserts into 't1'.
#
# 1.4 DESCRIBE statement.
#
# This statement does not really read data from the
# target table and thus does not take any lock on it.
# We check this for completeness of coverage.
lock table t1 write;
# Switching to connection 'con1'.
# This statement should not be blocked.
describe t1;
# Switching to connection 'default'.
unlock tables;
#
# 1.5 SHOW statements.
# 
# The above is true for SHOW statements as well.
lock table t1 write;
# Switching to connection 'con1'.
# These statements should not be blocked.
show keys from t1;
# Switching to connection 'default'.
unlock tables;
#
# 2. Statements which read tables through subqueries.
#
#
# 2.1 CALL with a subquery.
# 
# A strong lock is not necessary as this statement is not
# written to the binary log as a whole (it is written
# statement-by-statement).
Success: 'call p1((select i + 5 from t1 where i = 1))' allows concurrent inserts into 't1'.
#
# 2.2 CREATE TABLE with a subquery.
#
# Has to take a strong lock on the table being read as
# this statement is written to the binary log and therefore
# should be serialized with concurrent statements.
Success: 'create table t0 select * from t1' doesn't allow concurrent inserts into 't1'.
drop table t0;
Success: 'create table t0 select j from t2 where j in (select i from t1)' doesn't allow concurrent inserts into 't1'.
drop table t0;
#
# 2.3 DELETE with a subquery.
#
# The above is true for this statement as well.
Success: 'delete from t2 where j in (select i from t1)' doesn't allow concurrent inserts into 't1'.
#
# 2.4 MULTI-DELETE with a subquery.
#
# Same is true for this statement as well.
Success: 'delete t2 from t3, t2 where k = j and j in (select i from t1)' doesn't allow concurrent inserts into 't1'.
#
# 2.5 DO with a subquery.
#
# A strong lock is not necessary as it is not logged.
Success: 'do (select i from t1 where i = 1)' allows concurrent inserts into 't1'.
#
# 2.6 INSERT with a subquery.
#
# Has to take a strong lock on the table being read as
# this statement is written to the binary log and therefore
# should be serialized with concurrent inserts.
Success: 'insert into t2 select i+5 from t1' doesn't allow concurrent inserts into 't1'.
Success: 'insert into t2 values ((select i+5 from t1 where i = 4))' doesn't allow concurrent inserts into 't1'.
#
# 2.7 LOAD DATA with a subquery.
# 
# The above is true for this statement as well.
Success: 'load data infile '../../std_data/rpl_loaddata.dat' into table t2 (@a, @b) set j= @b + (select i from t1 where i = 1)' doesn't allow concurrent inserts into 't1'.
#
# 2.8 REPLACE with a subquery.
# 
# Same is true for this statement as well.
Success: 'replace into t2 select i+5 from t1' doesn't allow concurrent inserts into 't1'.
Success: 'replace into t2 values ((select i+5 from t1 where i = 4))' doesn't allow concurrent inserts into 't1'.
#
# 2.9 SELECT with a subquery.
#
# Strong locks are not necessary as this statement is not written
# to the binary log and thanks to how MyISAM works this statement
# sees a version of the table prior to the concurrent insert.
Success: 'select * from t2 where j in (select i from t1)' allows concurrent inserts into 't1'.
#
# 2.10 SET with a subquery.
#
# The same is true for this statement as well.
Success: 'set @a:= (select i from t1 where i = 1)' allows concurrent inserts into 't1'.
#
# 2.11 SHOW with a subquery.
# 
# And for this statement too.
Success: 'show tables from test where Tables_in_test = 't2' and (select i from t1 where i = 1)' allows concurrent inserts into 't1'.
Success: 'show columns from t2 where (select i from t1 where i = 1)' allows concurrent inserts into 't1'.
#
# 2.12 UPDATE with a subquery.
#
# Has to take a strong lock on the table being read as
# this statement is written to the binary log and therefore
# should be serialized with concurrent inserts.
Success: 'update t2 set j= j-10 where j in (select i from t1)' doesn't allow concurrent inserts into 't1'.
#
# 2.13 MULTI-UPDATE with a subquery.
#
# Same is true for this statement as well.
Success: 'update t2, t3 set j= j -10 where j=k and j in (select i from t1)' doesn't allow concurrent inserts into 't1'.
#
# 3. Statements which read tables through a view.
#
#
# 3.1 SELECT statement which uses some table through a view.
#
# Since this statement is not written to the binary log and
# an old version of the table is accessible thanks to how MyISAM
# handles concurrent insert, no locking is necessary.
Success: 'select * from v1' allows concurrent inserts into 't1'.
Success: 'select * from v2' allows concurrent inserts into 't1'.
Success: 'select * from t2 where j in (select i from v1)' allows concurrent inserts into 't1'.
Success: 'select * from t3 where k in (select j from v2)' allows concurrent inserts into 't1'.
#
# 3.2 Statements which modify a table and use views.
#
# Since such statements are going to be written to the binary
# log they need to be serialized against concurrent statements
# and therefore should take strong locks on the data read.
Success: 'update t2 set j= j-10 where j in (select i from v1)' doesn't allow concurrent inserts into 't1'.
Success: 'update t3 set k= k-10 where k in (select j from v2)' doesn't allow concurrent inserts into 't1'.
Success: 'update t2, v1 set j= j-10 where j = i' doesn't allow concurrent inserts into 't1'.
Success: 'update v2 set j= j-10 where j = 3' doesn't allow concurrent inserts into 't1'.
#
# 4. Statements which read tables through stored functions.
#
#
# 4.1 SELECT/SET with a stored function which does not 
#     modify data and uses SELECT in its turn.
#
# In theory there is no need to take strong locks on the table
# being selected from in SF as the call to such function
# won't get into the binary log. In practice, however, we
# discover that fact too late in the process to be able to
# affect the decision what locks should be taken.
# Hence, strong locks are taken in this case.
Success: 'select f1()' doesn't allow concurrent inserts into 't1'.
Success: 'set @a:= f1()' doesn't allow concurrent inserts into 't1'.
#
# 4.2 INSERT (or other statement which modifies data) with
#     a stored function which does not modify data and uses
#     SELECT.
#
# Since such statement is written to the binary log it should
# be serialized with concurrent statements affecting the data
# it uses. Therefore it should take strong lock on the data
# it reads.
Success: 'insert into t2 values (f1() + 5)' doesn't allow concurrent inserts into 't1'.
#
# 4.3 SELECT/SET with a stored function which
#     reads and modifies data.
#
# Since a call to such function is written to the binary log,
# it should be serialized with concurrent statements affecting
# the data it uses. Hence, a strong lock on the data read
# should be taken.
Success: 'select f2()' doesn't allow concurrent inserts into 't1'.
Success: 'set @a:= f2()' doesn't allow concurrent inserts into 't1'.
#
# 4.4. SELECT/SET with a stored function which does not
#      modify data and reads a table through subselect
#      in a control construct.
#
# Again, in theory a call to this function won't get to the
# binary log and thus no strong lock is needed. But in practice
# we don't detect this fact early enough (get_lock_type_for_table())
# to avoid taking a strong lock.
Success: 'select f3()' doesn't allow concurrent inserts into 't1'.
Success: 'set @a:= f3()' doesn't allow concurrent inserts into 't1'.
Success: 'select f4()' doesn't allow concurrent inserts into 't1'.
Success: 'set @a:= f4()' doesn't allow concurrent inserts into 't1'.
#
# 4.5. INSERT (or other statement which modifies data) with
#      a stored function which does not modify data and reads
#      the table through a subselect in one of its control
#      constructs.
#
# Since such statement is written to the binary log it should
# be serialized with concurrent statements affecting data it
# uses. Therefore it should take a strong lock on the data
# it reads.
Success: 'insert into t2 values (f3() + 5)' doesn't allow concurrent inserts into 't1'.
Success: 'insert into t2 values (f4() + 6)' doesn't allow concurrent inserts into 't1'.
#
# 4.6 SELECT/SET which uses a stored function with
#      DML which reads a table via a subquery.
#
# Since call to such function is written to the binary log
# it should be serialized with concurrent statements.
# Hence reads should take a strong lock.
Success: 'select f5()' doesn't allow concurrent inserts into 't1'.
Success: 'set @a:= f5()' doesn't allow concurrent inserts into 't1'.
#
# 4.7 SELECT/SET which uses a stored function which
#     doesn't modify data and reads tables through
#     a view.
#
# Once again, in theory, calls to such functions won't
# get into the binary log and thus don't need strong
# locks. But in practice this fact is discovered
# too late to have any effect.
Success: 'select f6()' doesn't allow concurrent inserts into 't1'.
Success: 'set @a:= f6()' doesn't allow concurrent inserts into 't1'.
Success: 'select f7()' doesn't allow concurrent inserts into 't1'.
Success: 'set @a:= f7()' doesn't allow concurrent inserts into 't1'.
#
# 4.8 INSERT which uses stored function which
#     doesn't modify data and reads a table
#     through a view.
#
# Since such statement is written to the binary log and
# should be serialized with concurrent statements affecting
# the data it uses. Therefore it should take a strong lock on
# the table it reads.
Success: 'insert into t3 values (f6() + 5)' doesn't allow concurrent inserts into 't1'.
Success: 'insert into t3 values (f7() + 5)' doesn't allow concurrent inserts into 't1'.
#
# 4.9 SELECT which uses a stored function which
#     modifies data and reads tables through a view.
#
# Since a call to such function is written to the binary log
# it should be serialized with concurrent statements.
# Hence, reads should take strong locks.
Success: 'select f8()' doesn't allow concurrent inserts into 't1'.
Success: 'select f9()' doesn't allow concurrent inserts into 't1'.
#
# 4.10 SELECT which uses a stored function which doesn't modify
#      data and reads a table indirectly, by calling another
#      function.
#
# In theory, calls to such functions won't get into the binary
# log and thus don't need to acquire strong locks. But in practice
# this fact is discovered too late to have any effect.
Success: 'select f10()' doesn't allow concurrent inserts into 't1'.
#
# 4.11 INSERT which uses a stored function which doesn't modify
#      data and reads a table indirectly, by calling another
#      function. 
#
# Since such statement is written to the binary log, it should
# be serialized with concurrent statements affecting the data it
# uses. Therefore it should take strong locks on data it reads.
Success: 'insert into t2 values (f10() + 5)' doesn't allow concurrent inserts into 't1'.
#
# 4.12 SELECT which uses a stored function which modifies
#      data and reads a table indirectly, by calling another
#      function. 
#
# Since a call to such function is written to the binary log
# it should be serialized from concurrent statements.
# Hence, read should take a strong lock.
Success: 'select f11()' doesn't allow concurrent inserts into 't1'.
#
# 4.13 SELECT that reads a table through a subquery passed
#      as a parameter to a stored function which modifies
#      data.
#
# Even though a call to this function is written to the
# binary log, values of its parameters are written as literals.
# So there is no need to acquire strong locks for tables used in
# the subquery.
Success: 'select f12((select i+10 from t1 where i=1))' allows concurrent inserts into 't1'.
#
# 4.14 INSERT that reads a table via a subquery passed
#      as a parameter to a stored function which doesn't
#      modify data.
#
# Since this statement is written to the binary log it should
# be serialized with concurrent statements affecting the data it
# uses. Therefore it should take strong locks on the data it reads.
Success: 'insert into t2 values (f13((select i+10 from t1 where i=1)))' doesn't allow concurrent inserts into 't1'.
#
# 5. Statements that read tables through stored procedures.
#
#
# 5.1 CALL statement which reads a table via SELECT.
#
# Since neither this statement nor its components are
# written to the binary log, there is no need to take
# strong locks on the data it reads.
Success: 'call p2(@a)' allows concurrent inserts into 't1'.
#
# 5.2 Function that modifies data and uses CALL, 
#     which reads a table through SELECT.
#
# Since a call to such function is written to the binary
# log, it should be serialized with concurrent statements.
# Hence, in this case reads should take strong locks on data.
Success: 'select f14()' doesn't allow concurrent inserts into 't1'.
#
# 5.3 SELECT that calls a function that doesn't modify data and
#     uses a CALL statement that reads a table via SELECT.
#
# In theory, calls to such functions won't get into the binary
# log and thus don't need to acquire strong locks. But in practice
# this fact is discovered too late to have any effect.
Success: 'select f15()' doesn't allow concurrent inserts into 't1'.
#
# 5.4 INSERT which calls function which doesn't modify data and
#     uses CALL statement which reads table through SELECT.
#
# Since such statement is written to the binary log it should
# be serialized with concurrent statements affecting data it
# uses. Therefore it should take strong locks on data it reads.
Success: 'insert into t2 values (f15()+5)' doesn't allow concurrent inserts into 't1'.
#
# 6. Statements that use triggers.
#
#
# 6.1 Statement invoking a trigger that reads table via SELECT.
#
# Since this statement is written to the binary log it should
# be serialized with concurrent statements affecting the data
# it uses. Therefore, it should take strong locks on the data
# it reads.
Success: 'insert into t4 values (2)' doesn't allow concurrent inserts into 't1'.
#
# 6.2 Statement invoking a trigger that reads table through
#     a subquery in a control construct.
#
# The above is true for this statement as well.
Success: 'update t4 set l= 2 where l = 1' doesn't allow concurrent inserts into 't1'.
#
# 6.3 Statement invoking a trigger that reads a table through
#     a view.
#
# And for this statement.
Success: 'delete from t4 where l = 1' doesn't allow concurrent inserts into 't1'.
#
# 6.4 Statement invoking a trigger that reads a table through
#     a stored function.
#
# And for this statement.
Success: 'insert into t5 values (2)' doesn't allow concurrent inserts into 't1'.
#
# 6.5 Statement invoking a trigger that reads a table through
#     stored procedure.
#
# And for this statement.
Success: 'update t5 set l= 2 where l = 1' doesn't allow concurrent inserts into 't1'.
# Clean-up.
drop function f1;
drop function f2;
drop function f3;
drop function f4;
drop function f5;
drop function f6;
drop function f7;
drop function f8;
drop function f9;
drop function f10;
drop function f11;
drop function f12;
drop function f13;
drop function f14;
drop function f15;
drop view v1, v2;
drop procedure p1;
drop procedure p2;
drop table t1, t2, t3, t4, t5;
set @@global.concurrent_insert= @old_concurrent_insert;
#
# Test for bug #45143 "All connections hang on concurrent ALTER TABLE".
#
# Concurrent execution of statements which required weak write lock
# (TL_WRITE_ALLOW_WRITE) on several instances of the same table and
# statements which tried to acquire stronger write lock (TL_WRITE,
# TL_WRITE_ALLOW_READ) on this table might have led to deadlock.
drop table if exists t1;
drop view if exists v1;
# Create auxiliary connections used through the test.
# Reset DEBUG_SYNC facility before using it.
set debug_sync= 'RESET';
# Turn off logging so calls to locking subsystem performed
# for general_log table won't interfere with our test.
set @old_general_log = @@global.general_log;
set @@global.general_log= OFF;
create table t1 (i int) engine=InnoDB;
# We have to use view in order to make LOCK TABLES avoid
# acquiring SNRW metadata lock on table.
create view v1 as select * from t1;
insert into t1 values (1);
# Prepare user lock which will be used for resuming execution of
# the first statement after it acquires TL_WRITE_ALLOW_WRITE lock.
select get_lock("lock_bug45143_wait", 0);
get_lock("lock_bug45143_wait", 0)
1
# Switch to connection 'con_bug45143_1'.
# Sending:
insert into t1 values (get_lock("lock_bug45143_wait", 100));;
# Switch to connection 'con_bug45143_2'.
# Wait until the above INSERT takes TL_WRITE_ALLOW_WRITE lock on 't1'
# and then gets blocked on user lock 'lock_bug45143_wait'.
# Ensure that upcoming SELECT waits after acquiring TL_WRITE_ALLOW_WRITE
# lock for the first instance of 't1'.
set debug_sync='thr_multi_lock_after_thr_lock SIGNAL parked WAIT_FOR go';
# Sending:
select count(*) > 0 from t1 as a, t1 as b for update;;
# Switch to connection 'con_bug45143_3'.
# Wait until the above SELECT ... FOR UPDATE is blocked after
# acquiring lock for the the first instance of 't1'.
set debug_sync= 'now WAIT_FOR parked';
# Send LOCK TABLE statement which will try to get TL_WRITE lock on 't1':
lock table v1 write;;
# Switch to connection 'default'.
# Wait until this LOCK TABLES statement starts waiting for table lock.
# Allow SELECT ... FOR UPDATE to resume.
# Since it already has TL_WRITE_ALLOW_WRITE lock on the first instance
# of 't1' it should be able to get lock on the second instance without
# waiting, even although there is another thread which has such lock
# on this table and also there is a thread waiting for a TL_WRITE on it.
set debug_sync= 'now SIGNAL go';
# Switch to connection 'con_bug45143_2'.
# Reap SELECT ... FOR UPDATE
count(*) > 0
1
# Switch to connection 'default'.
# Resume execution of the INSERT statement.
select release_lock("lock_bug45143_wait");
release_lock("lock_bug45143_wait")
1
# Switch to connection 'con_bug45143_1'.
# Reap INSERT statement.
# In Statement and Mixed replication mode we get here "Unsafe 
# for binlog" warnings. In row mode there are no warnings.
# Hide the discrepancy.
# Switch to connection 'con_bug45143_3'.
# Reap LOCK TABLES statement.
unlock tables;
# Switch to connection 'default'.
# Do clean-up.
set debug_sync= 'RESET';
set @@global.general_log= @old_general_log;
drop view v1;
drop table t1;
#
# Bug#50821 Deadlock between LOCK TABLES and ALTER TABLE
#
DROP TABLE IF EXISTS t1, t2;
CREATE TABLE t1(id INT);
CREATE TABLE t2(id INT);
# Connection con2
START TRANSACTION;
SELECT * FROM t1;
id
# Connection default
# Sending:
ALTER TABLE t1 ADD COLUMN j INT;
# Connection con2
# This used to cause a deadlock.
INSERT INTO t2 SELECT * FROM t1;
COMMIT;
# Connection default
# Reaping ALTER TABLE t1 ADD COLUMN j INT
DROP TABLE t1, t2;
#
# Bug#51391 Deadlock involving events during rqg_info_schema test
#
CREATE EVENT e1 ON SCHEDULE EVERY 5 HOUR DO SELECT 1;
CREATE EVENT e2 ON SCHEDULE EVERY 5 HOUR DO SELECT 2;
# Connection con1
SET DEBUG_SYNC="before_lock_tables_takes_lock SIGNAL drop WAIT_FOR query";
# Sending:
DROP EVENT e1;;
# Connection default
SET DEBUG_SYNC="now WAIT_FOR drop";
SELECT name FROM mysql.event, INFORMATION_SCHEMA.GLOBAL_VARIABLES
WHERE definer = VARIABLE_VALUE;
name
SET DEBUG_SYNC="now SIGNAL query";
# Connection con1
# Reaping: DROP EVENT t1
# Connection default
DROP EVENT e2;
SET DEBUG_SYNC="RESET";