Using transactions

[soycharliente]

I'm using MySQL database version 5.0

 

I read this thread and found this code:

 

START TRANSACTION
INSERT INTO inventory (character, item) VALUES ('B','dagger');
if (error) { ROLLBACK; exit; }
DELETE FROM inventory WHERE character = 'A' and item = 'dagger';
if (error) { ROLLBACK; exit; }
UPDATE characters SET money=money-20 WHERE character = 'B'
if (error) { ROLLBACK; exit; }
UPDATE characters SET money=money+20 WHERE character = 'A'
if (error) { ROLLBACK; exit; }
COMMIT

 

Can someone help me understand what this specific line of code in it means?

if (error)

 

Is that meant as pseudocode? If it's pseudocode, how can I capture an error? I've been looking at site after site with "tutorials" about doing transactions and I cannot figure it out. I don't have any code to show for what I've tried because up until I found that code, I couldn't even find a straight answer about how to structure it. Also, a developer buddy of mine said to look into using SET AUTOCOMMIT=0 and then SET AUTOCOMMIT=1 somewhere.

 

Thanks.

[fenway]

Yes, it's pseudo-code -- you have to capture the errors from mysql.