Bug 68676

Summary: ODBC: optionally use W variants of ODBC calls
Product: LibreOffice Reporter: Lionel Elie Mamane <lionel>
Component: BaseAssignee: Not Assigned <libreoffice-bugs>
Status: NEW ---    
Severity: enhancement CC: iplaw67, jmadero.dev, mentoring
Priority: medium Keywords: difficultyInteresting, easyHack, skillCpp, skillSql
Version: 4.2.0.0.alpha0+ Master   
Hardware: All   
OS: All   
See Also: https://bugs.documentfoundation.org/show_bug.cgi?id=131238
Whiteboard:
Crash report or crash signature: Regression By:
Bug Depends on:    
Bug Blocks: 104790    

Description Lionel Elie Mamane 2013-08-28 17:51:45 UTC 
Currently, LibreOffice only uses the "ANSI" variants of the ODBC calls, never the Unicode variants (with a W suffix). However, much (but not all) of the code is actually prepared to use the Unicode variants.

Using the Unicode variants can be useful because it allows us not to mess with encodings, we get more-or-less directly the UTF-16 that our OUStrings need. Also, it allows to work around bugs in ODBC drivers, see e.g. the discussion in comment 13 of bug 68426. But it may trigger *other* bugs in ODBC drivers...

Some decision needs to be done when to use which variant. Possibly it should just be an "Advanced setting" (see menu edit / database / advanced settings), or even better something set in the same dialog tab as the connection charset.

See in directory connectivity/source/drivers/odbcbase/:

 - OTools.cxx: argument _bUseWChar to various functions

 - OPreparedStatement.cxx: constant useWChar

 - OResultsetMetaData.cxx: this one is not ready;
   need to use N3SQLColAttribute OR  N3SQLColAttributeW
   depending on conditions / configuration / ...

directory connectivity/source/drivers/odbc/:

 - OFunctions.cxx

 - ORealDriver.cxx

these to add the W variants to these two functions.

There is a good explanation on ODBC and Unicode in general at
http://www.easysoft.com/products/data_access/odbc_oracle_driver/unicode.html#odbc
the authoritative reference is at
http://msdn.microsoft.com/en-us/library/windows/desktop/ms716246(v=vs.85).aspx
http://msdn.microsoft.com/en-us/library/windows/desktop/ms709439(v=vs.85).aspx
Comment 1 Alex Thurgood 2015-01-03 17:39:26 UTC Comment hidden (no-value)
Comment 2 Robinson Tryon (qubit) 2015-12-13 13:24:12 UTC Comment hidden (obsolete)
Comment 3 Robinson Tryon (qubit) 2016-02-18 14:52:23 UTC Comment hidden (obsolete)