FreeTDS Development Group

["James K. Lowden" <jklowden AT freetds.org>]

ú×ÅÒÅ× ÷ÉÔÁÌÉÊ âÏÒÉÓÏ×ÉÞ wrote:
> James, Frediano,
> thanks for comments in friendly atmosphere (I'm not a native English
> writer, so excuse me my ugly essay)

When I can apologize for my Russian, I'll pass judgement on your English,
Vitaly.  :-)

You're undertaking something ambitious and potentially very useful.  Being
friendly is pretty easy by comparison.  

I am hoping that you will write a function that will accept an SQL string,
find the placeholders, and return an array of structures.  Each structure
will contain:

        database
        system object name
        system object type (S/U/P/V/TR, per sysobjects)
        column/parameter name

In this query, for example:

        select * from systypes where name = ?

The answer would be:

        database = NULL
        object name = 'systypes'
        object type = 'S'
        column/parameter name = 'name'
        
The caller of your function will formulate a query for the server about
the datatype of each placeholder.  To do that it may need  to know if the
placeholder is a parameter to a stored procedure or function, or will be
compared to a column.  Not everything can be found in syscolumns.  

> BTW, FireBird like a Sybase has open interface to parametrised Dinamic
> SQL parser & ODBC driver (with SQLDescribeParam implementation)
> http://cvs.sourceforge.net/viewcvs.py/*checkout*/firebird/firebird2/src/dsql/parse.y?rev=1.193.
> 

Yep.  Firebird has a very different design and SQL.  I know a little about
it.  I contributed patches that made sure it runs on NetBSD.  

Regards, 

--jkl