FreeTDS Development Group

[James K. Lowden <jklowden AT speakeasy.org>]

All, 

We now have dbwillconvert().  

There is an implementation niggle wiggle.  

There is a new include file that I did not add to cvs:

         src/tds/tds_willconvert.h

If you look at the comments above tds_willconvert in tds/convert.c, you'll
find that tds_willconvert.h is a perl-generated file, and that the
requisite perl is embedded in said comments.  So, it's really not
necessary to have tds_willconvert.h in the archive.  Perl can generate it
and probably should.  

It would be cool, I think, to add this dependency to the auto* stuff.  I
don't know how, but there's time for that.  Until then, if you want to use
the function, follow the instructions in the comments.  Or grab the file
from:

http://www.SchemaMania.org/freetds/cvs/freetds/src/tds/tds_willconvert.h

+++

You may also wish to peruse:

http://www.SchemaMania.org/freetds/cvs/freetds/src/dblib/unittests/

for a file "convert_acid.c".  It takes any query and attempts to convert
every returned value to every available datatype.  "Attempt" is the
operative word, it perhaps should go without saying:

select 1 as one, '9' as nine    <== the query

2 columns returned.

column_name:     one
column_type:      56
column_size:      4
length:   4
data (first word):       
1
[56,47]         '0001' -> '1'
Will not convert 56, 39
Will not convert 56, 38
[56,48]         '0001' -> '1'
[56,52]         '0001' -> '01'
[56,56]         '0001' -> '0001'
Will not convert 56, 127
[56,62]         No output converting 4 bytes of 56 to 62
Will not convert 56, 61
[56,50]         No output converting 4 bytes of 56 to 50
[56,35]         No output converting 4 bytes of 56 to 35
[...]

"will not convert" means dbwillconvert returned FALSE.
"no output" means we called dbconvert, but it returned zero.
else it prints what it got.

(The [56,35] are the #define'd SYB* values in tds.h.)  

If you're curious about what works and what doesn't this will show you.  

Regards, 

--jkl

$ cvs diff -u -r 1.100 ChangeLog
jklowden AT cvs.freetds.sourceforge.net's password: 
Index: ChangeLog
===================================================================
RCS file: /cvsroot/freetds/freetds/ChangeLog,v
retrieving revision 1.100
retrieving revision 1.102
diff -u -r1.100 -r1.102
--- ChangeLog   9 Jul 2002 03:15:46 -0000       1.100
+++ ChangeLog   11 Jul 2002 05:55:42 -0000      1.102
@@ -1,3 +1,17 @@
+Thu Jul 11 01:47:47 EDT 2002
+       + src/tds/convert.c, implement tds_willconvert
+       + include/tds_willconvert.h, perl-generated static data 
+       + src/tds/convert.c, implement tds_willconvert
+       * src/dblib/dblib.c, implement dbwillconvert via tds_willconvert
+
+Tue Jul  9 23:16:12 EDT 2002 JK Lowden <jklowden AT schemamania.org>
+       declare TDSUNIQUE in the same way as windows and unixodbc
(Frediano):
+       + include/tds.h.in, patch #579149.
+       + src/tds/convert.c, patch #579149
+       * src/tds/convert.c, simplify tds_convert_text
+       * src/dblib/dblib.c, fix dbconvert to work with new
tds_convert_text
+       * src/tds/token.c, tds_process_row, fix little endian numeric
datatype (Bill Thompson)
+
 Mon Jul  8 19:03:33 EDT 2002 JK Lowden <jklowden AT schemamania.org>
        * src/tds/convert.c: reverted tds_convert_text to 1.12 logic; 
                1.13 patch was mistaken, per Brian.