Wed Oct 30 08:51:43 EST 2002
amplodbc.c, ampltabl.dll, TABLES.RME:  extend the "standard" ODBC
table handler to recognize new optional string maxlen=nnn (just before
the optional 'verbose') among the Strings to specify the maximum
length of strings (symbolic parameters) read from the table.  The
default is 480, which will probably suffice for most purposes.
Strings longer than maxlen will be truncated to maxlen characters when
the table is read.

Tue Aug  5 22:51:54 EDT 2003
amplodbc.c, ampltabl.dll:  have "write table" preserve old columns
of an INOUT table even when the table is initially empty, and for
columns of type text, retain the text type even when the column
ends up having exlusively numeric values.

Tue Dec  6 09:59:00 EST 2005
amplodbc.c: minor tweaks for portability to 64-bit MS Windows.

Tue Jan  1 17:57:59 MST 2008
amplodbc.c:  tweak for MS SQL Server 2005:  for numeric values,
successively try SQL_DOUBLE, SQL_FLOAT, SQL_REAL, and SQL_NUMERIC
rather than SQL_DOUBLE, SQL_NUMERIC, and SQL_REAL.

Wed Jan  2 23:25:35 MST 2008
amplodbc.c:  adjust the date shown when "version" is specified.
(Missed updating this lately when making changes.)

Thu Sep 23 13:31:28 MDT 2010
amplodbc.c:  attempt to pass a plausible window handle to
SQLDriverConnect().  If need be, a handle can be specified by setting
$sw_HWND to a hexadecimal value (without a leading 0x) in the
environment passed to AMPL.  With some incomplete or incorrect
DRIVER=...  settings, this will cause a dialogue box to appear
in which corrections can be attempted.  Setting $sw_HWND to 0
disables this new behavior.
  Ignore case for "DRIVER=", "SQL=", and "DSN=" (e.g., treat "Driver="
and "driver=" the same as "DRIVER=").

Tue Nov  2 17:26:08 MDT 2010
amplodbc.c:  fix a bug that led to a seldom-seen error message of
the form "ColAlloc: cols[5].sinv already allocated."

20111024
  amplodbc.c: Add optional strings 'nsmix=...' and 'write=append' or
'write=drop' to the possibilities for strings in table declarations
for tables handled by the ODBC table handler (usually called
ampltabl.dll), and allow 'verbose=n', with 0 <= n <= 3, as
alternatives to 'verbose'.  For details, in an AMPL session with
the updated ampltabl.dll loaded, issue the command
	print _handler_desc['odbc'];

20120306
  amplodbc.c:  Fix a glitch with the default 'nsmix' that caused
some numeric strings, such as 100000 (but not 10000) to be treated
as string rather than numeric values.  Fix a bug in parsing
"write=drop" or "write=append" that sometimes resulted in an erroneous
error message.
  fullbit.c, simpbit.c: allow optional strings 'lib-bit' or 'simple-bit'.
  Add source files tableproxy.c and tableproxyver.h; add rules involving
them to makefile.linux and makefile.vc; omit makefile.sgi.
See http://www.ampl.com/NEW/TABLEPROXY/ .

20120315
  amplodbc.c:  Fix a glitch in the error message for missing columns:
a buffer was too small, leading to a possible fault with tables having
many columns.
   There appears to be a bug in some versions of Microsoft's ODBC
processing for Excel that causes too few columns to be reported for
tables having more than 255 columns.  This may only be an issue with
*.xlsx files, as MS Access and Excel limit (most or all?) other
kinds of files they produce to at most 255 columns.

20120402
 tableproxy.c:  fix faults in tableproxy*.exe in processing some error
messages and recycling string buffers.

20120405
 tableproxy.c:  when a shared-library name (such as ampltabl.dll)
does not contain a slash (or, for MS Windows, start with a drive
letter), have tableproxy*.exe look in $ampl_libpath (if set) for the
library.  Note that AMPL versions starting with 20120404 export
$ampl_libpath.  When $ampl_libpath is not set, behave as though
$ampl_libpath were set to the current directory.

20120530
 amplodbc.c:  fix a bug with error messages that prevented some
possibly helpful details from being reported.

20121212
  amplodbc.c:  adjustments by Victor Zverovich to make ODBC table
handlers for Linux with unixODBC (http://www.unixodbc.org) or iODBC
(http://www.iodbc.org) in adition to MS Windows (as heretofore).
  README: update to mention _HANDLERS, _handler_desc, and recent
extensions to simplify mixing 32- and 64-bit binaries.
  Split makefile.linux into makefile.linux and makefile.linux64
(for making 32- and 64-bit entities, respectively, and adjusting
to include both the ODBC and tableproxy handlers in ampltabl.dll,
with a new rule for tableproxy.dll that just has the tableproxy
handler.

20121213
  README: add descriptions of _handler_lib, _table_errmsg, and
_version; add reminder that $AMPLFUNC provides full pathnames.
  Adding makefile.macosx32 and makefile.macosx64 for Intel MacOSX.
  Renaming makefile.linux to makefile.linux32.

20121219
  amplodbc.c: tweaks for 64-bit Linux systems that use unixODBC
but with a 32-bit type for SQLLEN (rather than the 64-bit type
that unixODBC specifies).

20130214
  amplodbc.c:  tweak to bypass a bug with long names in Microsoft's
Excel ODBC driver -- thanks to Victor Zverovich.

20130318
  amplodbc.c: for connection strings involving, e.g.,
	'Driver={Microsoft Text Driver (*.txt; *.csv)};DBQ=.'
do not complain if DBQ=... specifies a directory.

20130326
  amplodbc.c: under MS Windows, ignore trailing slashes when
checking the validity of DBQ=... strings.

20130417
  amplodbc.c:  fix a glitch in reading tables with null columns.
Thanks go to Victor Zverovich for this fix.

20130507
  amplodbc.c:  Fix a fault when no "User DSN" or "System DSN"
entries appear in the MS Windows ODBC Administrator and the
filename in a table declaration ends with an unknown extension.
Thanks go to Victor Zverovich for this fix.

20130607
  tableproxy.c, tableprxyver.h: fix a bug in the tableproxy program
that could lead to duplicate rows.  Thanks go to Victor Zverovich
for this fix.

20130815
  amplodbc.c:  fix faults with "write table" of a table that in
AMPL's view is empty but whose existing file-based version contains
at least one row.

20131122
 tableproxy.c, tableproxyver.h:  arrange for 'verbose' output (written
to the printf supplied by the tableproxy table handler) to be returned
to the AMPL session.  This requires both a current tableproxy program
and tableproxy*.dll (or ampltabl.dll that incorporates the tableproxy
handler).  Have the tableproxy program ignore case when comparing
handler names.
 amplodbc.c: "invisible" tweak: use printf rather than fprintf to
report a malloc failure.  (This is for tableproxy, so all output
comes via printf.)

20131212
  amplodbc.c:  under MS Windows, use GetDesktopWindow() rather than
EnumWindows() to get the window handle for SQLDriverConnect().  Thanks
to Victor Zverovich for suggesting this change.

20140125
  tableproxy.c:  fix a bug in ampltabl.dll with reading empty tables
via the tableproxy handler.  Have "tableproxy -v" show system details.

20140525
  tableproxy.c: Read_ampl_proxy: when table reading is finished and
TI->Errmsg is set, return DB_Error rather than DB_Done.

20141003
  tableproxy.c:  have the tableproxy program ignore SIGINT when talking
with the tableproxy handler over a pipe (i.e., when invoked with --local).
This prevents trouble with interactive use of AMPL when the user types
control-C.  Thanks to Victor Zverovich for diagnosing this issue.

20150217
  amplodbc.c:  fix a glitch in strcmpv() that caused it to sort on
string addresses rather than string values.  Thanks to
peter.jackson@rtdmsolutions.com for pointing this out.

20151130
  amplodbc.c:  fix a glitch in reading columns with the "Strcol:"
attribute:  strings that looked like numbers were read as numbers.

20190307
  amplodbc.c:  only issue error message "Could not find SQL synonym
for SQL_TIMESTAMP" if the synonym is needed.
  README: various updates.

20190517
  TABLES.RME:  fix a typo on line 124:  change "->" to "<-", so the
line becomes "FOOD <- [FOOD] cost, f_min, f_max;".

20210502
  fullbit.c, simpbit.c, tableproxy.c:  tweaks to banish pedantic
compiler warnings.  No change to tableproxyver.h.