List:General Discussion« Previous MessageNext Message »
From:Tom Crimmins Date:March 16 2005 4:09pm
Subject:RE: Queries inside UDF
View as plain text  
On Wednesday, March 16, 2005 09:30, sguazt sguazt wrote:

> Hi folks!
> 
> (I hope this is the right list ... if not please tell me where I can
> submit this post)
> 
> I would like to create a MySQL UDF (i.e. User Defined Function) that
> embeds a query; for instance, suppose the UDF is named foobar:
> 
> mysql> SELECT foobar();
> 
> When foobar function receives the control from the MySQL, it attempts
> to create a query. To do so it has to connect to DB (since it seems
> there's no way to access to current DB connection from a UDF function
> -- at least I did'nt find it any way). So the flow of execution is:
> SELECT foobar()
> 1 --> Call foobar
> 2 -----> init MySQL
> 3 -----> connect to MySQL
> 4 -----> create/execute query
> 5 -----> get query result
> 6 -----> close MySQL connection
> 7 -----> return result

 [...snip...]

>   const char* query = "SELECT COUNT(*) FROM tblfoobar";

Can you explain exactly what you are using this for? What benefit does this 
provide over just executing the query?

You can either execute SELECT foobar() or SELECT COUNT(*) FROM tblfoobar,
and 
you don't have to do anything to make the latter work. Creating the UDF just

seems like a lot of extra work. Maybe this is my ignorance, but I don't see 
much use for executing a query within a UDF esspecially if you are using 4.1

with subqueries.

-- 
Tom Crimmins
Interface Specialist
Pottawattamie County, Iowa
Thread
Queries inside UDFsguazt sguazt16 Mar
RE: Queries inside UDFTom Crimmins16 Mar
  • RE: Queries inside UDFsguazt sguazt16 Mar
    • RE: Queries inside UDFSGreen16 Mar
      • RE: Queries inside UDFsguazt sguazt16 Mar
        • RE: Queries inside UDFSGreen16 Mar
RE: Queries inside UDFsguazt sguazt17 Mar
  • Re: Queries inside UDFPhilippe Poelvoorde17 Mar
    • Re: Queries inside UDFsguazt sguazt17 Mar
      • Re: Queries inside UDFPhilippe Poelvoorde21 Mar
        • Re: Queries inside UDFsguazt sguazt25 Mar