mariadb/mysql-test/t/trigger.test

#
# Basic triggers test
#

--disable_warnings
drop table if exists t1, t2;
drop view if exists v1;
--enable_warnings

create table t1 (i int);

# let us test some very simple trigger
create trigger trg before insert on t1 for each row set @a:=1;
set @a:=0;
select @a;
insert into t1 values (1);
select @a;
drop trigger t1.trg;

# let us test simple trigger reading some values 
create trigger trg before insert on t1 for each row set @a:=new.i;
insert into t1 values (123);
select @a;
drop trigger t1.trg;

drop table t1;

# Let us test before insert trigger
# Such triggers can be used for setting complex default values
create table t1 (i int not null, j int);
delimiter |;
create trigger trg before insert on t1 for each row 
begin 
  if isnull(new.j) then
    set new.j:= new.i * 10;
  end if;
end|
insert into t1 (i) values (1)|
insert into t1 (i,j) values (2, 3)|
select * from t1|
drop trigger t1.trg|
drop table t1|
delimiter ;|

# After insert trigger
# Useful for aggregating data
create table t1 (i int not null primary key);
create trigger trg after insert on t1 for each row 
  set @a:= if(@a,concat(@a, ":", new.i), new.i);
set @a:="";
insert into t1 values (2),(3),(4),(5);
select @a;
drop trigger t1.trg;
drop table t1;

# Before update trigger
# (In future we will achieve this via proper error handling in triggers)
create table t1 (aid int not null primary key, balance int not null default 0);
insert into t1 values (1, 1000), (2,3000);
delimiter |;
create trigger trg before update on t1 for each row 
begin
  declare loc_err varchar(255);
  if abs(new.balance - old.balance) > 1000 then
    set new.balance:= old.balance;
    set loc_err := concat("Too big change for aid = ", new.aid);
    set @update_failed:= if(@update_failed, concat(@a, ":", loc_err), loc_err);
  end if;
end|
set @update_failed:=""|
update t1 set balance=1500|
select @update_failed;
select * from t1|
drop trigger t1.trg|
drop table t1|
delimiter ;|

# After update trigger
create table t1 (i int);
insert into t1 values (1),(2),(3),(4);
create trigger trg after update on t1 for each row 
  set @total_change:=@total_change + new.i - old.i;
set @total_change:=0;
update t1 set i=3;
select @total_change;
drop trigger t1.trg;
drop table t1;

# Before delete trigger
# This can be used for aggregation too :)
create table t1 (i int);
insert into t1 values (1),(2),(3),(4);
create trigger trg before delete on t1 for each row 
  set @del_sum:= @del_sum + old.i;
set @del_sum:= 0;
delete from t1 where i <= 3;
select @del_sum;
drop trigger t1.trg;
drop table t1;

# After delete trigger. 
# Just run out of imagination.
create table t1 (i int);
insert into t1 values (1),(2),(3),(4);
create trigger trg after delete on t1 for each row set @del:= 1;
set @del:= 0;
delete from t1 where i <> 0;
select @del;
drop trigger t1.trg;
drop table t1;

# Several triggers on one table
create table t1 (i int, j int);

delimiter |;
create trigger trg1 before insert on t1 for each row 
begin
  if new.j > 10 then
    set new.j := 10;
  end if;
end|
create trigger trg2 before update on t1 for each row 
begin
  if old.i % 2 = 0 then
    set new.j := -1;
  end if;
end|
create trigger trg3 after update on t1 for each row 
begin
  if new.j = -1 then
    set @fired:= "Yes";
  end if;
end|
delimiter ;|
set @fired:="";
insert into t1 values (1,2),(2,3),(3,14);
select @fired;
select * from t1;
update t1 set j= 20;
select @fired;
select * from t1;

drop trigger t1.trg1;
drop trigger t1.trg2;
drop trigger t1.trg3;
drop table t1;


#
# Test of wrong column specifiers in triggers
#
create table t1 (i int);

--error 1363
create trigger trg before insert on t1 for each row set @a:= old.i;
--error 1363
create trigger trg before delete on t1 for each row set @a:= new.i;
--error 1362
create trigger trg before update on t1 for each row set old.i:=1;
--error 1363
create trigger trg before delete on t1 for each row set new.i:=1;
--error 1362
create trigger trg after update on t1 for each row set new.i:=1;
# TODO: We should also test wrong field names here, we don't do it now
#       because proper error handling is not in place yet.


#
# Let us test various trigger creation errors
#
#
--error 1146
create trigger trg before insert on t2 for each row set @a:=1;

create trigger trg before insert on t1 for each row set @a:=1;
--error 1359
create trigger trg after insert on t1 for each row set @a:=1;
--error 1359
create trigger trg2 before insert on t1 for each row set @a:=1;
drop trigger t1.trg;

--error 1360
drop trigger t1.trg;

create view v1 as select * from t1;
--error 1361
create trigger trg before insert on v1 for each row set @a:=1;
drop view v1;

drop table t1;

create temporary table t1 (i int);
--error 1361
create trigger trg before insert on t1 for each row set @a:=1;
drop table t1;



#
# Tests for various trigger-related bugs
#

# Test for bug #5887 "Triggers with string literals cause errors".
# New .FRM parser was not handling escaped strings properly.
create table t1 (x1col char);  
create trigger tx1 before insert on t1 for each row set new.x1col = 'x';
insert into t1 values ('y');
drop trigger t1.tx1;
drop table t1;

#
# Test for bug #5890 "Triggers fail for DELETE without WHERE".
# If we are going to delete all rows in table but DELETE triggers exist
# we should perform row-by-row deletion instead of using optimized
# delete_all_rows() method.
#
create table t1 (i int) engine=myisam;
insert into t1 values (1), (2);
create trigger trg1 before delete on t1 for each row set @del_before:= @del_before + old.i;
create trigger trg2 after delete on t1 for each row set @del_after:= @del_after + old.i;
set @del_before:=0, @del_after:= 0;
delete from t1;
select @del_before, @del_after;
drop trigger t1.trg1;
drop trigger t1.trg2;
drop table t1;