DBD::Unify --  a Unify interface for Perl 5 using DBI.

This is the Database Driver for the Unify family of database products.
See http://support.guptatechnologies.com/supportwiki/index.php/Platforms
for Unify DataServer products.

See the ChangeLog file for a complete history

REQUIREMENTS

    It has been ported and tested on DataServer 6.3AB, 6.3BE, 8.1CC, 8.1CE,
    8.1DAB, 8.2AC, 8.2AD, 8.2B, 8.2BC, 8.3E/64, 8.3F/64, 8.3I/64, 8.3KAB/64,
    and 9.1B, but this does not mean it might not work on U2000 databases or
    other DataServer releases.

    I have tested with DBI-1.632 .. DBI 1.643 and perl-5.8.6 through 5.34.0,
    but you might get it to work with DBI 0.93 or higher.  But then again, in
    that case you should consider an upgrade. As of DBD-Unify-0.40 I've made
    DBI-1.42 prerequisite.  DBD-Unify-0.70 raised the minimum supported
    perl version to perl-5.6 and version 0.90 raised it to perl-5.8.6.

    The test case however uses scalarIO to catch errors, so if you use a
    perl that does not support scalarIO (e.g. perlIO enabled), you will
    have to disable the failing tests that use it yourself and hope for
    the best (or better, upgrade to a perl that supports scalarIO).

    Don't expect anything Unicode releated DataServer data to work on perl
    versions below 5.8.4 (if you get it to work at all).  Note that $LANG
    will need to match your database locale. See the Unicode site for the
    differences between the Unicode standards if you want to know what to
    expect (http://www.unicode.org/versions/enumeratedversions.html) and
    http://www.unicode.org/history/publicationdates.html for their age.

      Perl version
      Stable  Devel   Unicode
      ------  ------- -------
              5.35.4   14.0.0  UCD 14.0.0 released 14 Sep 2021
      5.32.0  5.31.10  13.0.0  UCD 13.0.0 released 10 Mar 2020
      5.30.0  5.29.10  12.1.0  UCD 12.1.0 released 07 May 2019
              5.29.9   12.0.0  UCD 12.0.0 released 05 Mar 2019
              5.29.2   11.0.0  UCD 11.0.0 released 05 Jun 2018
      5.28.0  5.27.2   10.0.0  UCD 10.0.0 released 20 Jun 2017
      5.26.0  5.25.3    9.0.0  UCD  9.0.0 released 21 Jun 2016
      5.24.0  5.23.0    8.0.0  UCD  8.0.0 released 17 Jun 2015
      5.22.0  5.21.1    7.0.0  UCD  7.0.0 released 16 Jun 2014
      5.20.0  5.19.5    6.3.0  UCD  6.3.0 released 30 Sep 2013
      5.18.0  5.17.1    6.2.0  UCD  6.2.0 released 26 Sep 2012
      5.16.0  5.15.8    6.1.0  UCD  6.1.0 released 31 Jan 2012
      5.14.0  5.13.7    6.0.0  UCD  6.0.0 released 11 Oct 2010
      5.12.0  5.11.3    5.2.0  UCD  5.2.0 released 01 Oct 2009
      5.10.1  5.10.1    5.1.0  UCD  5.1.0 released 04 Apr 2008
      5.10.0  5.9.5     5.0.0  UCD  5.0.0 released 14 Jul 2006
      5.8.7   5.8.7     4.1.0  UCD  4.1.0 released 31 Mar 2005
      5.8.5   5.8.5     4.0.1  UCD  4.0.1 released    Mar 2004
      5.8.1   5.8.1     4.0.0  UCD  4.0.0 released 24 Apr 2003
      5.8.0   5.8.0     3.2.0  UCD  3.2.0 released 02 Apr 2002
              5.7.x     3.1.1  UCD  3.1.1 released    Aug 2001
                        3.0.x  UCD  3.0.0 released    Sep 1999
                               UCD  1.0.0 draft was planned spring 1991 :)

    Use 'corelist -a Unicode' to see the complete list of what version of
    Unicode is shipped with what version of perl.

    One user has reported success with perl 5.005_03 on SunOS 5.7 with
    gcc-2.7.2.2, DBI-1.30, DBD-Unify-0.24 with DataServer-7.2.

    Todd Zervas reported working versions:
    - 0.65 working on 32bit 9.0G on Linux 2.4.21-47.EL
    - 0.76 working on 32bit 9.0G on Linux 2.6.18-92.1.22.el5PAE
    - 0.77 working on 32bit 9.0G on Linux 2.6.18-128.1.14.el5PAE
		   with GNU g++ 4.1.2, perl-5.8.8, and DBI-1.609
    - 0.89 working on 64bit 9.1D on Linux 2.6.32-642.6.2   (RHEL 6.7)
		   with DBI 1.623
    - 0.90 working on 64bit 9.1E on Linux 3.10.0-1062.12.1 (RHEL 7.7)
		   with DBI 1.627 and Perl 5.16.3

BUILDING, TESTING AND INSTALLING:

    This will only work if DBI is installed on a recent version of perl ;-)
    and you are working in a valid Unify environment. Makefile.PL will stop
    with a warning if you are not.

	   # perl Makefile.PL

    This step will ask you if you need networked databases. Probably you do
    not, which is the default answer. Choosing 'Yes' will include two more
    libraries that are broken in 8.1CC for HP-UX. Choosing 'No' will prefer
    U2000ul.a and S2000ul.a over U2000u.a and S2000u.a resulting in smaller
    binaries with local-only support.

    If you are using gcc, it might be needed to explicitly tell Unify to
    use it, because ucc defaults to cc (always):

	   # export UPPNAME=/usr/local/pa20_32/bin/gcc
	   # export UCCNAME=/usr/local/pa20_32/bin/gcc
	   # export ULDNAME=/usr/local/pa20_32/bin/gcc

    Another approach would be:

	   # ln -s /usr/local/pa20_32/bin/gcc cc
	   # export PATH=".:$PATH"

    Now you need to build the objects:

	   # make

    And if that succeeds, run the tests:

	   # make test

    Make test will use the current database and create a table "xx". If
    the test fails, table xx might still exist. If it already exists,
    it might get lost, so be aware!

    Make test will try to test all DBI features found in the DBI-1.19 docs
    even some that are not DBD dependent. Partly to show that it still works
    for DBD::Unify, and partly to find what features are still to be
    implemented. Features known to fail will issue an ok when ran with
    make test, but will show additional comments with a todo tag when run
    directly (e.g. 'perl t/11-dbi-dbh.t'). Note that the t/21-uni-regex test
    skips the test for 'SHLIKE' because this will cause core dumps. Advice:
    do *not* use SHLIKE, but use REGLIKE (which is quite easy to convert to
    from SHLIKE). All versions above A/SQL 8.2AC should have this problem
    solved. The test is enabled by default. If you have an older (crashing)
    version, disable this test by removing the hash in line

      #if ("This test is known to fail") { ok ("shlike will core", 1) } else

    If you happen to have a DataServer only product (no accell), make
    will probably complain about a missing ACCELL.a from Makefile.PL
    The workaround seems to be to remove the reference to ACCELL.a from
    Makefile.PL (reported by Ron Kuris)

	   # make install

    Will install the DBD::Unify extension into the default perl path's. If
    you plan to run different perl versions and/or different Unify versions
    alongside eachother, use the installu.pl script instead, which installs
    DBD::Unify in the Unify tree [ .../lib/perl ], and extend the environment
    variable $PERL5LIB with $UNIFY/perl

	  # make installu

    As with all modules: Patches are welcome.

SOURCE CODE

    Recent changes can be (re)viewed in the public GIT repository at
    https://github.com/perl5-dbi/DBD-Unify
    Feel free to clone your own copy:

     $ git clone https://github.com/perl5-dbi/DBD-Unify DBD-Unify

    or get it as a tgz:

     $ wget --output-document=DBD-Unify.tgz \
            https://github.com/perl5-dbi/DBD-Unify/archive/master.tar.gz

SHARED BUILDS on HP-UX

    As of somewhere in the DataServer 8.2 track, Unify has finally indulged
    to my request for shared library prepared objects, at least on HP-UX,
    where they only ship static libraries. Objects inside these libraries
    are now built with the +Z option, so it is easy to convert the static
    libraries (.a) to shared libraries (.sl). The Makefile build process
    will propose such transition, and - once succeeded - use it for the now
    shared object, which is *much* smaller than when built statically. This
    does not always work. If things fail, choose for the static route.
    
NAMING CONFLICTS

    In their enormous wisdom, Unify have chosen a function named "inflate"
    to be exported in their libraries. This will conflict with libz. If
    you use any module that uses a shared lib that requires libz, this
    will result in core dumps that are hard to trace. A possible solution
    is to rename the function *after* building. This is - of course - very
    very very dirty, but if it works, it will circumvent the problem:

     $ make
     $ perl -pi -e's/\0inflate\0/\0InFlate\0/g' \
          blib/arch/auto/DBD/Unify/Unify.so
     $ make test

RESTRICTIONS:

    This is a basic port for Unify. At the moment of writing, this DBD
    does not support all DBI elements, methods and attributes. I'll add
    these the moment I need them myself, or one of you will supply them
    as patches.

    DATE and TIME fields are not fully supported. The database interaction
    works, but there are some issues left to iron out in the user
    interface. We're working on it. Suggestions welcome.

    TEXT and BINARY fields are supported as of version 0.60, but probably
    not fully tested. Feedback and patches welcome.

    Other known restrictions:

    # Incomplete or out-of-date documentation, though I keep trying to
      keep in pace with what I change

    # Some database attributes not (yet) implemented. (AutoCommit et all)

    # Most statement attributes are now implemented. Those needed for
      $sth->fetchrow_hashref () now work, but STORE_attrib () doesn't.

      DBD::Unify tries to return the {TYPE} attribute in ANSI/ODBC DBI
      compliant coding, and has the original Unify field type available
      in the {uni_types} attribute. For AMOUNT and HUGE AMOUNT however,
      ANSI has no defined codes. These will be returned as SQL_FLOAT and
      SQL_DOUBLE, with the {SCALE} set to 2.

    And deficiencies/shortcommings that come with Unify:

    # Unify does not supply the "NULLABLE" indicator when describing
      fields, the returned value is as documented always 2.

    # Unify does not return the desired length of non-character type
      fields, but the /maximum/ PRECISION for those fields

    # Unify has no VARCHAR concept

    # Unify only distributes static libraries, so the module might
      become rather big. Libraries on AIX are always shared, and some
      of Unify's libraries can safely be converted to shared libs,
      but that is no guarantee to work.

    # At least until 8.2, Unify library pool does *NOT* allow more then
      one different database open at the same time from within the same
      process (even when the first database has correctly disconnected
      and closed) :-(

      This problem is known  with Unify and registered in their bug
      database as 'usb100963: disconnect'. Unify Sacramento has finally
      located the bug's source after yet again I reported this in
      bug report 22960. DBD-Unify 0.25 and up have a workaround for all
      versions up to and including 8.2AD. It's fixed in 8.2B.

TODO:

    See module documentation for specific TODO items

    # Remove as many restrictions as possible
    # Add more tests
    # Investigate if LIKE and SHLIKE operators in positional parameters
      indeed do not work (I've seen that, but found no time yet to look
      into this more). Currently it cores on SHLIKE. See t/21-uni-regex.t
    # Try finding ways to increase performance, squeezing every last
      nanosecond out of each handle
    # If you're into Unify internals, try finding out why describing
      positional parameters in where clauses (not in selected fields)
      causes a core dump on the field name. Look in dbdimp.ic in function
      dbd_prm_describe () for comment about OSF/1.

ACKNOWLEDGEMENTS

    Thanks to Tom Poage <poage@fireball.ucdmc.ucdavis.edu> for keeping
    the speed in the early development and help in adding the missing
    features in the earlier stages of this DBD interface.

    Thanks to Todd Zervas <tazervas@earthlink.net> for digging in the
    binary issues on DS 9.0.

COPYRIGHT AND LICENSE

    Copyright (C) 1999-2023  H.Merijn Brand <h.m.brand@xs4all.nl>

    This library is free software; you can redistribute it and/or modify
    it under the same terms as Perl itself. 

As always, have the appropriate amount of fun!
