But what about stored procedures? I don't seen any examples of calling an SP using DB at all.
On Sun, Feb 16, 2014 at 11:14 AM, Sean McBeth <sean.mcb...@gmail.com> wrote: > aaah, okay, thanks. > > > On Sun, Feb 16, 2014 at 11:13 AM, Ryan Culpepper <ry...@ccs.neu.edu>wrote: > >> On 02/15/2014 05:11 PM, Sean McBeth wrote: >> >>> All of the examples in the documentation for the db package use either >>> question-mark placeholders or numbered placeholders, i.e. >>> "select * from some_table where some_column = ?" >>> "select * from some_table where some_column = $1" >>> >>> The three databases that I use (SQL Server, MySQL, and Postgres) all >>> support the question mark syntax, but you can only refer to a single >>> parameter once in a query with the question mark. >>> >>> MySQL and Postgres support numbered parameters, but SQL Server does not. >>> Or at least, not that I'm aware of. I've never seen anyone use it that >>> way, and I can't find any examples online. >>> >>> Regardless, I rather much prefer named parameters, anyway, as it makes >>> the queries easier to read. >>> "select * from some_table where some_column = $param1" >>> >>> I know MySQL, Postgres, AND SQL Server all can support this style (well, >>> replacing $ with @ for SQL Server), because I have a boat load of C# >>> code doing it right now. >>> >>> But there is no indication of how to execute such a query in Racket with >>> DB. >>> >> >> The PostgreSQL server itself only supports "$N" parameters. The MySQL >> server (AFAIK) only supports "?" parameters. >> >> Support for other parameter syntaxes may be added by the particular >> library or driver you're using to communicate with the back end. For >> example, I think ODBC drivers all support "?" placeholders. >> >> The Racket db library doesn't add support for other parameter syntaxes, >> and I have no plans to add it. (Not in terms of rewriting strings of SQL >> code, anyway; possibly from a structured representation of SQL code.) >> >> You could write the translation(s) using proper tokenizer(s) or regexps >> that happen to work on the queries in your program and then create a >> statement wrapper using prop:statement that would run the translator for >> the appropriate dialect. >> >> Ryan >> >> >
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