Re: Server side prepared statements 'bit' parameters generate errors.

On 10/04/2016 07:35 AM, Johan Levin wrote:
> Hello
>
> I have run into a problem after upgrading from 9.03 to the 9.05.04 ODBC
> driver. Parameters of type 'bit' seem to be interpreted as 'char' in
> some cases when using server side prepared statements.
>
> If I execute the query
> select * from some_table where ?;
> with a bit parameter then I get an error that reads:
> ERROR [42804] ERROR: argument of WHERE must be type boolean, not
> type "char";
>
> The error is not reproducible is I set the connection string
> parameter UseServerSidePrepare=0. It also isn't reproducible in version
> 9.03 regardless of the value of UseServerSidePrepare. The problem seems
> to only affect bit parameters. A program that duplicates the problem
> follows at the end of this email. I am using the driver distributed in
> "psqlodbc_09_05_0400-x64.zip" on Windows 10. I have tested PostgreSQL
> version 9.4 and 9.5.
>
> Have I run into a bug in the driver, or is this a server issue? Any help
> would be much appreciated.

Got to believe it is related to:

https://odbc.postgresql.org/docs/release.html
"
psqlODBC 09.05.0100 Release

....

12. Send datatype information for query parameters, when known
If a query parameter is bound with a specific SQL type, pass on that
information to the server. This makes the behaviour of queries like
"SELECT '555' > ?" more sensible, where the result depends on whether
the query parameter is interpreted as an integer or a string.

....

"

>
> Regards,
> Johan Levin
>
>
>
>
> Program listing: (C#)
>
> using System.Data.Odbc;
> using System.Diagnostics;
> internal class Program
> {
> private static void Main(string[] args)
> {
> // Command line: Server, User, Password, Database,
> UseServerSidePrepare
> // Database schema and data:
> // create table some_table (id int, name varchar(20));
> // insert into some_table values (42, 'Arthur Dent');
>
> Trace.Assert(args.Length == 5, "Wrong number of command line
> arguments.");
> var connStr = string.Format("Driver={{PostgreSQL
> Unicode(x64)}};Server={0};Uid={1};Pwd={2};Database={3};UseServerSidePrepare={4}",
> args);
> using (var connection = new OdbcConnection(connStr))
> using (var command = connection.CreateCommand())
> {
> connection.Open();
> command.CommandText = "select * from some_table where ?;";
> command.Parameters.Add(new OdbcParameter
> {
> OdbcType = OdbcType.Bit,
> Value = 1
> });
> command.ExecuteNonQuery(); // <-- Exception here if
> UseServerSidePrepare=1
> // OdbcException.Message =
> // ERROR [42804] ERROR: argument of WHERE must be type
> boolean, not type "char";
> // Error while executing the query
> }
> }
> }
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com