[Dbix-class] InflateColumn DateTime tricks with MSSQL/Microsoft_SQL_Server

[Michael Higgins]

On Tue, 15 Jan 2008 09:01:49 -0800
Marc Mims <marc at questright.com> wrote:
[snip]
> 
> I think Michael is using
> DBIx::Class::Storage::ODBC::Microsoft_SQL_Server, which doesn't
> provide build_datetime_parser---yet.  I need to add that. Actually,
> DBI::MSSQL and DBI::ODBC::Microsoft_SQL_Server need to be unified,
> but I hesitate to do that without assistance from someone actually
> using DBI::MSSQL so we can ensure the unified code works on both the
> DBD::ODBC and DBD::Sybase layers.
> 
> Micheal, make a local copy of Microsoft_SQL_Server and copy the
> build_date_time_parser method from DBI::MSSQL into it.  If that works
> as expected, then I'll add it Microsoft_SQL_Server and commit it.

Added this:


sub build_datetime_parser {
  my $self = shift;
  my $type = "DateTime::Format::Strptime";
  eval "use ${type}";
  $self->throw_exception("Couldn't load ${type}: $@") if $@;
  return $type->new( pattern => '%m/%d/%Y %H:%M:%S.%3N' );
}

I did that, basically, as it seemed to be the thing to do. 

The error is:

Can't call method "mdy" on an undefined value

What I don't get is where InflateColumn::DateTime chooses which flavor
of SQL to honor.

> 
> However, inflation/deflation may not be the whole problem, here.  If I
> read your original message correctly, you were trying to use a
> DateTime object in a search.  There is no inflate/deflate done,
> there.  It's just stringification.

No, the search is fine using a string. What happens is the record is
returned, but accessing the data fails.

> 
> If you have a valid DateTime object at that point, then $dt->mdy('/')
> should do what you expect.

I know. It doesn't.

Can anyone figure out how InflateColumn::DateTime gets the storage
engine string to pick the right syntax? I put this in my loop, to be
sure it hadn't been changed:

print $schema->storage_type;

::DBI::ODBC::Microsoft_SQL_Server
::DBI::ODBC::Microsoft_SQL_Server
::DBI::ODBC::Microsoft_SQL_Server
::DBI::ODBC::Microsoft_SQL_Server
::DBI::ODBC::Microsoft_SQL_Server
::DBI::ODBC::Microsoft_SQL_Server
::DBI::ODBC::Microsoft_SQL_Server
::DBI::ODBC::Microsoft_SQL_Server
::DBI::ODBC::Microsoft_SQL_Server
PK: 155392
Can't call method "mdy" on an undefined value 

On the first record it attempts to pull and print.

-- 
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 michael.higgins[at]evolone[dot]org