Re: Can MySQL start/fire an external process?

Mark Matthews wrote: 
You can do pretty much anything you want in a UDF (make a socket call,
run some Java code using jUDF, exec() an external process, etc), which
you can call from a trigger:

I would not recommend doing anything in a UDF that could execute in unbounded time, perform I/O, access other libraries, etc.
Doing so can result in:
- security vulnerabilities, because the UDF runs as the user id of the DBMS server
- DBMS server hanging if your UDF takes a long time to return
- DBMS server crashing if your UDF has a bug, or fails to handle exception cases

UDFs are intended for very short-duration context-free operations, taking input parameters and giving output based solely on that input.
I would not recommend designing a UDF to read or write any state outside the scope of the UDF.

Regards,
Bill K.
.

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