drop database if exists demo;
create database demo;
use demo;
create procedure proc_top_a(p1 integer)
begin
## DECLARE CONTINUE HANDLER for SQLEXCEPTION, NOT FOUND
begin
end;
select "Starting ...";
call proc_middle_a(p1);
select "The end";
end
$$
create procedure proc_middle_a(p1 integer)
begin
DECLARE l integer;
# without RESIGNAL:
# Should be: DECLARE EXIT HANDLER for SQLEXCEPTION, NOT FOUND
DECLARE EXIT HANDLER for 1/* not sure how to handle exceptions */
begin
select "Oops ... now what ?";
end;
select "In prod_middle()";
create temporary table t1(a integer, b integer);
select GET_LOCK("user_mutex", 10) into l;
insert into t1 set a = p1, b = p1;
call proc_bottom_a(p1);
select RELEASE_LOCK("user_mutex") into l;
drop temporary table t1;
end
$$
create procedure proc_bottom_a(p1 integer)
begin
select "In proc_bottom()"; if (p1 = 1) then
begin
select "Doing something that works ...";
select * from t1;
end;
end if; if (p1 = 2) then
begin
select "Doing something that fail (simulate an error) ...";
drop table no_such_table;
end;
end if; if (p1 = 3) then
begin
select "Doing something that *SHOULD* works ...";
select * from t1;
end;
end if;
end
$$
call proc_top_a(1);
Starting ...
Starting ...
In prod_middle()
In prod_middle()
In proc_bottom()
In proc_bottom()
Doing something that works ...
Doing something that works ...
a b 11
The end
The end
call proc_top_a(2);
Starting ...
Starting ...
In prod_middle()
In prod_middle()
In proc_bottom()
In proc_bottom()
Doing something that fail (simulate an error) ...
Doing something that fail (simulate an error) ... ERROR42S02: Unknown table 'demo.no_such_table'
call proc_top_a(3);
Starting ...
Starting ...
In prod_middle()
In prod_middle() ERROR42S01: Table 't1' already exists
call proc_top_a(1);
Starting ...
Starting ...
In prod_middle()
In prod_middle() ERROR42S01: Table 't1' already exists
drop temporary table if exists t1;
create procedure proc_top_b(p1 integer)
begin
select "Starting ...";
call proc_middle_b(p1);
select "The end";
end
$$
create procedure proc_middle_b(p1 integer)
begin
DECLARE l integer;
DECLARE EXIT HANDLER for SQLEXCEPTION, NOT FOUND
begin
begin
DECLARE CONTINUE HANDLER for SQLEXCEPTION, NOT FOUND
begin /* Ignore errors from the cleanup code */
end;
select "Doing cleanup !";
select RELEASE_LOCK("user_mutex") into l;
drop temporary table t1;
end;
RESIGNAL;
end;
select "In prod_middle()";
create temporary table t1(a integer, b integer);
select GET_LOCK("user_mutex", 10) into l;
insert into t1 set a = p1, b = p1;
call proc_bottom_b(p1);
select RELEASE_LOCK("user_mutex") into l;
drop temporary table t1;
end
$$
create procedure proc_bottom_b(p1 integer)
begin
select "In proc_bottom()"; if (p1 = 1) then
begin
select "Doing something that works ...";
select * from t1;
end;
end if; if (p1 = 2) then
begin
select "Doing something that fail (simulate an error) ...";
drop table no_such_table;
end;
end if; if (p1 = 3) then
begin
select "Doing something that *SHOULD* works ...";
select * from t1;
end;
end if;
end
$$
call proc_top_b(1);
Starting ...
Starting ...
In prod_middle()
In prod_middle()
In proc_bottom()
In proc_bottom()
Doing something that works ...
Doing something that works ...
a b 11
The end
The end
call proc_top_b(2);
Starting ...
Starting ...
In prod_middle()
In prod_middle()
In proc_bottom()
In proc_bottom()
Doing something that fail (simulate an error) ...
Doing something that fail (simulate an error) ...
Doing cleanup !
Doing cleanup ! ERROR42S02: Unknown table 'demo.no_such_table'
call proc_top_b(3);
Starting ...
Starting ...
In prod_middle()
In prod_middle()
In proc_bottom()
In proc_bottom()
Doing something that *SHOULD* works ...
Doing something that *SHOULD* works ...
a b 33
The end
The end
call proc_top_b(1);
Starting ...
Starting ...
In prod_middle()
In prod_middle()
In proc_bottom()
In proc_bottom()
Doing something that works ...
Doing something that works ...
a b 11
The end
The end
drop database demo;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.14 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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