DBD::Ingres --  an Ingres interface for Perl 5 using DBI.

This is the Database Driver for the Ingres family of database products.
It requires Ingres 6.4 or OpenIngres 1.0 or newer,
DBI 1.00 or newer, Perl5.004 or newer.

Note:
There are indications of memory corruption problems with Perl5.005_03.
As of now (1999.05.25) the advice is to use Perl5.005_02.


   Copyright (c) 1996,1997  Henrik Tougaard <ht@datani.dk>

   You may distribute under the terms of either the GNU General Public
   License or the Artistic License, as specified in the Perl README file.

New features:

V0.19_3     1999.05.25
  - Cleanup of the code. Removal of some/all (?!!) of the core dumps.
    No longer 'unaligned access'.
  - Redo the check for re-preparation (still croak if a commit/rollback
    has invalidated the statement).

    Possibly fit for human comsumption. ;-}

V0.19_2     1999.02.06
  - Added support for threaded perls, thanks to Alan Murray <murray@email.exide.
com>

V0.19_1     1998.11.11
  This is the first test of the forthcoming release 0.20. This is not
  for public consumption - please use with care.

  - Don't export $sql_dbh etc as default. (Ingperl.pm)
    Warning:
       This may break code that uses one or more of:
          $sql_drh $sql_dbh $sql_sth $sql_debug $sql_rowcount
       Change:
          use Ingperl;
       to:
          use Ingperl( qw[ $sql_dbh $sql_sth ] );
  - Added support for updateable cursors (experimental), Thanks to
    Dirk Koopman <djk@tobit.co.uk>.
  - Upgrade to support DBI 1.00 (experimental):
     . re-prepare statement, that have gone out of scope (eq. after a
       commit/rollback etc). Just first bash at it :-(, ie. for now just
       keep tabs on whether the statement is invalidated by commit.
     . add the new meta-data fields (TYPE, SCALE, PRECISION)
       Ingres doesn't return the SCALE information so that is undef untill
       further notice!
     . first bash at type_info_all
     . added $dbh->table_info (so $dbh->tables also works thanks to DBI)
     . added $dbh->ping
  - Changed statement name from stmnt<12-digit-number> to
    st<number>_<a-bit-of-the-select>, so that it maybe is possible to
    see which statement is executing from eg. ipm.
    This may have the adverse effect that Ingres runs out of buffer space,
    because it leaves all prepared statements in the ???-buffer untill a
    commit. This will only be a problem if you execute many different
    statements in a transaction.
    If this does become a problem please let me know. One solution is to
    allow the user to define the statement name if neccessary (eg. though
    the %attribs argument to prepare).
  - Cleaned up some code here and there.
  - OpenIngres 1.0 now requires patch 5301 (or later) as this fixes the
    unfortunate problem with nullability and outerjoins. The code to work
    around this problem is removed (it had strange sideeffects at times).
    This should not be a problem for OpenIngres 2.0 or later.
    It if definitely not a problem for Ingres 6.4; as outerjoins were
    introduced in OpenIngres.
####  - Now builds cleanly on NT without changes to the makefile.
####  - Now builds cleanly on VMS (again)
  - Now commits after inquiring for autocommit-state after connect. This
    removes the nedd for the commit in:
        $dbh = DBI->connect...
        $dbh->commit;
        $dbh->do("set lockmode....");

(Note #### = Not Yet Implemented)


BEFORE BUILDING, TESTING AND INSTALLING this you will need to:

    Build, test and install Perl 5.004 (or newer)
    It is very important to test it and install it!

    Build, test and install the DBI module.
    It is very important to test it and install it!
    *** DBI must be at least version 1.00 ***

BUILDING

    If Perl5 is installed do:

	perl Makefile.PL

    If Perl5 is NOT installed install it, and come back here later!

    Then do:

	make
	make test
	make install

    HP-UX users (and others) will have to build perl with static
    extensions:
        make perl
        make test
        make inst_perl
    See the MakeMaker docs for further: perldoc ExtUtils::MakeMaker

The make test pass will ask for at databasename (if not given in one of
the DBI environment variable (see DBI.pm for particulars). It will then
create a table named 'testhththt' in this database, manipulate it and
delete it again.
It is important for the succes of the test that you have the neccesary
Ingres permissions.

The ingtest.pl script is a "quick" hack of the test for ingperl (the
"old" perl4 interface).

If it fails horribly, see below.

Do NOT hand edit the generated Makefile unless you are completely sure
you understand the implications! Always try to make changes via the
Makefile.PL command line and/or editing the Makefile.PL.

You should never need to make any changes. If you do *please* let me
know so that I can try to make it automatic in a later release.

KNOWN PROBLEMS:

	o sometime prepared statements don't work - they either give the
	  wrong results, or they error out.
	  The problem seems to have appeared with one of the later patches
	  to Ingres...
	  Work-around: reprepare the statement everytime round 8^{

        o the arguments to &sql(connect) must be given in the order:
            database-name username other-options
          otherwise the check for username wil fail.

	o Problems have been reported on Digital Unix where the abflnk.opt
          files does not include '-ldnet_stub'. This will cause wierd errors
          during "make test" - somewhat like:
Can't load './blib/arch/auto/DBD/Ingres/Ingres.so' for module DBD::Ingres:
dlopen: Unresolved symbols at
/usr/local/lib/perl5/alpha-dec_osf/5.00404/DynaLoader.pm line 166.
          include '-ldnet_stub' in your abflnk.opt to fix this.

	o Lenio Eric <elenio@mct.rochester.edu> reports problems using
          GNU-ld on SunOS. The problems disappeared when he reverted to
          Sun's ld. Message was: "ld.so: Undefined symbol: _IIGCa_static"

TO DO LIST:

        o Add support for OpenIngres long datatypes.
        o Add a way to call database procedures.

IF YOU HAVE PROBLEMS:

Firstly, check the Frequently Asked Questions, Known Bugs and any other
pertinent documents at:

	http://www.symbolstone.org/technology/perl/DBI

If this does *not* resolve your problem, please post details to 
dbi-user@fugue.com and CC them to me at ht@datani.dk.  
Please include:

1. A complete log of a complete build, e.g.:

	perl Makefile.PL -v           (do a make realclean first)
	make
	make test
	DBI_TRACE=3 make test

2. Full details of which version of Ingres/esql and Perl you're using.

3. The output of:
	perl -e 'use Config; print Config::myconfig()'

4. If you get a core dump, try to include a stack trace from it.
   If the stack trace mentions XS_DynaLoader_dl_load_file then rerun
   make test after setting the environment variable PERL_DL_DEBUG to 2.
   Similarly, get the Devel::CoreStack module and use it.

5. Please don't post problems to comp.lang.perl.misc or perl5-porters.

6. If you are not currently subscribed to the mailing list please
   subscribe via http://www.fugue.com/dbi

Regards,
Tim, Al & Henrik.


Original document: (c)Tim Bunce <Tim.Bunce@ig.co.uk>
Amendments: (c)Alligator Descartes <descarte@informix.com>
Further amendments: (c)Henrik Tougaard <ht@datani.dk>
