Re: [Cppcms-users] CppDB: SQL Parameter for IN clause

[CN <cn...@fa...>]

On Wed, Mar 16, 2016, at 01:47 PM, Artyom Beilis wrote:
> First of all sorry for delayed reply - was offline for a while.

I am much grateful for your kind helps and marvelous CppCMS products.
 
> What I did in such a case I build manually a query with several
> placeholders
> according to number of iterms in IN clause and binded prameters later i.
> 
> 
> sql << "SELECT 1 FROM t WHERE c IN (?)" << 1 ;
> sql << "SELECT 1 FROM t WHERE c IN (?,?)" << 1 << 2;
> 
> and so on.
> 
> Currently there is no special placeholder for a variable number of
> parameters in CppDB

Your approach makes me think that there actually is no one-size-fit-all
solution for such use case. It looks like that the best I can do now is
to run time generate SQL text with variable number of question marks in
"IN ()" clause if I want the SQL to accept random number of values from
end users and then loop to bind these values to these question marks.

Thanks for the comments! 

Best Regards,
CN

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