Alastair Houghton wrote:
> On 5 Feb 2006, at 23:33, Wade Leftwich wrote:
> 
>> Wade Leftwich wrote:
>>
>>> Michael Bayer wrote:
>>>
>>>> ok, great.  if you want to look at the code, its pretty easy, its lib/
>>>> sqlalchemy/databases/mysql.py line 163, "reflecttable".  Right now  its
>>>> just "describe", loop through rows, a little parsing, then 
>>>> table.append_item(Column).  thanks !
>>>>
>>>> - mike
>>>
>>>
>>> See if this gets us at least partway down the road. Seems to work:
>>>
>>
>> I had an immediate attack of staircase wit. Here's a simpler version
>> that also works.
>>
>> -- Wade
> 
> 
>> +        match = re.search(r'\)\s*TYPE=(?P<ttype>.+)$', desc, re.I)
> 
> 
> This needs to say (?:TYPE|ENGINE), since some versions write ENGINE
> rather than TYPE here.
> 
> Kind regards,
> 
> Alastair.
> 

OK, here's one more try, with Alastair's correction and (I think) an
improvement on the search for tabletype, allowing for other info that
might precede or follow 'TYPE=InnoDB'.

-- Wade

Index: mysql.py
===================================================================
--- mysql.py	(revision 915)
+++ mysql.py	(working copy)
@@ -164,6 +164,9 @@
         # to use information_schema:
         #ischema.reflecttable(self, table, ischema_names, use_mysql=True)
         
+        tabletype, foreignkeyD = self.moretableinfo(table=table)
+        # XXX tabletype == 'InnoDB' or 'MyISAM', what do we do with it?
+        
         c = self.execute("describe " + table.name, {})
         while True:
             row = c.fetchone()
@@ -182,7 +185,44 @@
                 args = re.findall(r'(\d+)', args)
                 #print "args! " +repr(args)
                 coltype = coltype(*[int(a) for a in args])
-            table.append_item(schema.Column(name, coltype, primary_key=primary_key, nullable=nullable, default=default))
+            
+            arglist = []
+            fkey = foreignkeyD.get(name)
+            if fkey is not None:
+                arglist.append(schema.ForeignKey(fkey))
+    
+            table.append_item(schema.Column(name, coltype, *arglist,
+                                            **dict(primary_key=primary_key,
+                                                   nullable=nullable,
+                                                   default=default
+                                                   )))
+    
+    def moretableinfo(self, table):
+        """Return (tabletype, {colname:foreignkey,...})
+        execute(SHOW CREATE TABLE child) =>
+        CREATE TABLE `child` (
+        `id` int(11) default NULL,
+        `parent_id` int(11) default NULL,
+        KEY `par_ind` (`parent_id`),
+        CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`id`) ON DELETE CASCADE\n) TYPE=InnoDB
+        """
+        c = self.execute("SHOW CREATE TABLE " + table.name, {})
+        desc = c.fetchone()[1].strip()
+        tabletype = ''
+        lastparen = re.search(r'\)[^\)]*\Z', desc)
+        if lastparen:
+            match = re.search(r'\b(?:TYPE|ENGINE)=(?P<ttype>.+)\b', desc[lastparen.start():], re.I)
+            if match:
+                tabletype = match.group('ttype')
+        foreignkeyD = {}
+        fkpat = (r'FOREIGN KEY\s*\(`?(?P<name>.+?)`?\)'
+                 r'\s*REFERENCES\s*`?(?P<reftable>.+?)`?'
+                 r'\s*\(`?(?P<refcol>.+?)`?\)'
+                )
+        for match in re.finditer(fkpat, desc):
+            foreignkeyD[match.group('name')] = match.group('reftable') + '.' + match.group('refcol')
+
+        return (tabletype, foreignkeyD)
         
 
 class MySQLTableImpl(sql.TableImpl):

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