# Test of the READ_ONLY global variable:
# check that it blocks updates unless they are only on temporary tables.

# should work with embedded server after mysqltest is fixed
-- source include/not_embedded.inc

--disable_warnings
DROP TABLE IF EXISTS t1,t2,t3;
--enable_warnings

# READ_ONLY does nothing to SUPER users
# so we use a non-SUPER one:

grant CREATE, SELECT, DROP on *.* to test@localhost;

connect (con1,localhost,test,,test);

connection default;

set global read_only=0;

connection con1;

create table t1 (a int);

insert into t1 values(1);

create table t2 select * from t1;

connection default;

set global read_only=1;

# We check that SUPER can:

create table t3 (a int);
drop table t3;

connection con1;

select @@global.read_only;

--error 1290
create table t3 (a int);

--error 1290
insert into t1 values(1);

# if a statement, after parse stage, looks like it will update a
# non-temp table, it will be rejected, even if at execution it would
# have turned out that 0 rows would be updated
--error 1290
update t1 set a=1 where 1=0;

# multi-update is special (see sql_parse.cc) so we test it
--error 1290
update t1,t2 set t1.a=t2.a+1 where t1.a=t2.a;

# check multi-delete to be sure
--error 1290
delete t1,t2 from t1,t2 where t1.a=t2.a;

# With temp tables updates should be accepted:

create temporary table t3 (a int);

create temporary table t4 (a int) select * from t3;

insert into t3 values(1);

insert into t4 select * from t3;

# a non-temp table updated:
--error 1290
update t1,t3 set t1.a=t3.a+1 where t1.a=t3.a;

# no non-temp table updated (just swapped):
update t1,t3 set t3.a=t1.a+1 where t1.a=t3.a;

update t4,t3 set t4.a=t3.a+1 where t4.a=t3.a;

--error 1290
delete t1 from t1,t3 where t1.a=t3.a;

delete t3 from t1,t3 where t1.a=t3.a;

delete t4 from t3,t4 where t4.a=t3.a;

# and even homonymous ones

create temporary table t1 (a int);

insert into t1 values(1);

update t1,t3 set t1.a=t3.a+1 where t1.a=t3.a;

delete t1 from t1,t3 where t1.a=t3.a;

drop table t1;

--error 1290
insert into t1 values(1);

#
# BUG#11733: COMMITs should not happen if read-only is set
#

# LOCK TABLE ... WRITE / READ_ONLY
# - is an error in the same connection
# - is ok in a different connection

connection default;
set global read_only=0;
lock table t1 write;

connection con1;
lock table t2 write;

connection default;
--error ER_LOCK_OR_ACTIVE_TRANSACTION
set global read_only=1;
unlock tables ;
# The following call blocks until con1 releases the write lock.
# Blocking is expected.
send set global read_only=1;

connection con1;
--sleep 1
select @@global.read_only;
unlock tables ;
--sleep 1
select @@global.read_only;

connection default;
reap;

# LOCK TABLE ... READ / READ_ONLY
# - is an error in the same connection
# - is ok in a different connection

connection default;
set global read_only=0;
lock table t1 read;

connection con1;
lock table t2 read;

connection default;
--error ER_LOCK_OR_ACTIVE_TRANSACTION
set global read_only=1;
unlock tables ;
# The following call blocks until con1 releases the read lock.
# Blocking is a limitation, and could be improved.
send set global read_only=1;

connection con1;
--sleep 1
select @@global.read_only;
unlock tables ;
--sleep 1
select @@global.read_only;

connection default;
reap;

# pending transaction / READ_ONLY
# - is an error in the same connection
# - is ok in a different connection

connection default;
set global read_only=0;
BEGIN;

connection con1;
BEGIN;

connection default;
--error ER_LOCK_OR_ACTIVE_TRANSACTION
set global read_only=1;
ROLLBACK;
set global read_only=1;

connection con1;
select @@global.read_only;
ROLLBACK;

# Verify that FLUSH TABLES WITH READ LOCK do not block READ_ONLY
# - in the same SUPER connection
# - in another SUPER connection

connection default;
set global read_only=0;
flush tables with read lock;
set global read_only=1;
unlock tables;

connect (root2,localhost,root,,test);

connection default;
set global read_only=0;
flush tables with read lock;

connection root2;
set global read_only=1;

connection default;
select @@global.read_only;
unlock tables;

# BUG #22077 "DROP TEMPORARY TABLE fails with wrong error if read_only is set"
#
# check if DROP TEMPORARY on a non-existing temporary table returns the right
# error

--error ER_BAD_TABLE_ERROR
drop temporary table ttt;

# check if DROP TEMPORARY TABLE IF EXISTS produces a warning with read_only set
drop temporary table if exists ttt;

#
# Cleanup
#
connection default;
set global read_only=0;
drop table t1,t2;
drop user test@localhost;
