Show message in stored procedure

问题

How do I show a message from a stored procedure?

What is the right syntax to display a message saying whether or not rows exist?

In SQL Server it's PRINT to show a message bat in WORKBENCH...

CREATE PROCEDURE `new_proced` (
    in myid     int(3)
)
BEGIN
    if not exists (select id from table where id = myid)
then
    show message 'Row no exists';
else
    show message 'Row exists';
end if;
END

回答1:

Not entirely sure why you would want to do something like that, but you could do something like this: ...

then
  select 'YOUR MESSAGE HERE'  
else
  select 'YOUR OTHER MESSAGE HERE'
end if

Or you could select 1 or 0, might be a little better...

回答2:

There is no Proper output statement provide in MySQL like in Oracle, we have DBMS_OUTPUT.PUT_LINE. So, to display any messages on the console, you can use SELECT statement as:

SELECT message;

Eg: SELECT "WELCOME TO MySQL";

回答3:

For debugging info from stored procedure in MySQL,there are following options through which you can do this.

1.Write into the file externally:

select "your_message" as log into outfile '/temp/brajesh.txt';

2.Use select command to print message:

select "result_message";

3.Use select command to print additional information with message:

select concat("Hello ! :", result);

4.Create addition table temp and push all message into it:

insert into temp select concat(result);

Example

drop procedure if exists display_name_procedure;
delimiter //
create procedure display_name_procedure(IN name_val varchar(65))
begin
declare result varchar(65);
set result := display_name_function(name_val);

create table if not exists temp (name_val varchar(65) not null);
insert into temp select concat(result);
select "penguin" as log into outfile '/temp/brajesh.txt';
select concat("Hello ! :", result);

end//

delimiter ;

来源：https://stackoverflow.com/questions/20039398/show-message-in-stored-procedure

标签

mysql

stored-procedures

mysql-workbench