mikoil
October 26th, 2006, 02:48 PM
Hi!
I have this task:
I have a MySQL table (database) with this records:
ID File
~~ ~~~
1 f1.dat
2 f2.dat
3 f3.dat
4 f4.dat
And this table that holds only 1 record which is the current id, eg:
CurrentID
~~~~~~
{x}
I need my cgi to increase the CurrentID value and have the result. Also, reset to 1 if the CurrentID is 4 (end of the table).
Simple algo to make it clear:
if(CurrentID==4)
CurrentID=0;
CurrentID++;
The problem is that this cgi might be executed dozens of times per second, so I might get problems like my cgi would save an invalid value or something, I'm not really sure even :)
Is there a MySQL function to do this? Simply get CurrentID's value PLUS increase it by one, no matter how many "threads" are doing it in the same time?
I have this task:
I have a MySQL table (database) with this records:
ID File
~~ ~~~
1 f1.dat
2 f2.dat
3 f3.dat
4 f4.dat
And this table that holds only 1 record which is the current id, eg:
CurrentID
~~~~~~
{x}
I need my cgi to increase the CurrentID value and have the result. Also, reset to 1 if the CurrentID is 4 (end of the table).
Simple algo to make it clear:
if(CurrentID==4)
CurrentID=0;
CurrentID++;
The problem is that this cgi might be executed dozens of times per second, so I might get problems like my cgi would save an invalid value or something, I'm not really sure even :)
Is there a MySQL function to do this? Simply get CurrentID's value PLUS increase it by one, no matter how many "threads" are doing it in the same time?