TypeError: 'int' object is not iterable

I'm not sure if it will be relevant, but what DB are you using?

Just the default SQLite DB.

I have the exact same error on Trac v1.0 running on Gentoo Linux and python 2.7

Reproduced. The stacktrace is here.

...
  File "/home/jun66j5/venv/trac/1.0.1/lib/python2.5/site-packages/trac/wiki/formatter.py", line 343, in _macro_processor
    text)
  File "/home/jun66j5/src/trac/trac-hacks/wikitablemacro/trunk/wikitable/table.py", line 68, in expand_macro
    format_to_html(self.env, formatter.context, col)
  File "/home/jun66j5/venv/trac/1.0.1/lib/python2.5/site-packages/trac/wiki/formatter.py", line 1546, in format_to_html
    return HtmlFormatter(env, context, wikidom).generate(escape_newlines)
  File "/home/jun66j5/venv/trac/1.0.1/lib/python2.5/site-packages/trac/wiki/formatter.py", line 1501, in generate
    escape_newlines)
  File "/home/jun66j5/venv/trac/1.0.1/lib/python2.5/site-packages/trac/wiki/formatter.py", line 1237, in format
    for line in text:
TypeError: 'int' object is not iterable

The 3rd argument, wikidom, of format_to_html expects a instance of str, unicode or iterable.

Index: wikitable/table.py
===================================================================
--- wikitable/table.py  (revision 12643)
+++ wikitable/table.py  (working copy)
@@ -16,7 +16,7 @@
 from trac.wiki.formatter import system_message, format_to_html
 from trac.wiki.macros import WikiMacroBase
 from trac.util.html import Markup
-from trac.util.text import exception_to_unicode
+from trac.util.text import to_unicode, exception_to_unicode
 from trac.util.translation import _

 class SQLTable(WikiMacroBase):
@@ -64,6 +64,14 @@
             css_class = (idx % 2 == 0) and 'odd' or 'even'
             print >> out, "  <tr class='%s'>" % css_class
             for col in row:
+                if col is None:
+                    col = "''(NULL)''"
+                elif col is True:
+                    col = 'TRUE'
+                elif col is False:
+                    col = 'FALSE'
+                elif not isinstance(col, basestring):
+                    col = to_unicode(col)
                 print >> out, "<td>%s</td>" % \
                     format_to_html(self.env, formatter.context, col)
             print >> out, "  </tr>"

Thank you for the patch Jun. I'll test and apply it.

I don't have a lot of interest in this macro, so if someone else wants to take over maintenance I'm more than willing to hand it over.

(In [12646]) Fixes #10814: Patch by Jun Omae (jun66j5) to fix a regression introduced in [12459]. Ensure that a string is passed to format_to_html.

Lightly tested against Trac 1.1.2dev-r11682.