[Firebird-net-provider] Parameter handling

[<car...@te...>]

Hello:

I have some changes in my local tree, for start to make real use of 
parameter information ( FbParameter class ).

Until now on the command preparation the provider calls always the 
isc_dsql_describe_bind implementation method, to obtain parameter 
information, i have an initial implementation ( a little limited for now 
but enough for start testing ) for build the parameter information from 
FbParameter class, i think this can improve performance (not a great 
improve but a little at least).

It will do the call in any case if the parameter information cannot be 
correctly build ( for example if the length is 0 in char and varchar 
parameters ).

I will try to make some tests with the SqlParameter class for see in 
what situations it throws an exception ( i know there are some cases it 
do but not know the complete list :) ) for try to do the same in the 
FbParameter class

As this could break existing applications :P , i want to know opinions 
about this issue :)





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Best regards

Carlos Guzmán Álvarez
Vigo-Spain