node-mdb exception

[Alan Pound]

Ok, I've sorted out my data directory issue by linking in a new partition from /usr/local/gtm - a bit kludgy but it works.

I've spent quite a bit of time looking at the way it all sets up, and in the end I've stayed with the mgwtools process, as it works (even though it installs a lot more stuff than is needed).

However, I've noticed that node-mdb is very touchy with the exact way that selects are constructed - for example, if the wrong type of quotes are used (even arrangements that SDB is quite happy with ).  Again, not a problem as such, but I notice that node-mdb tends to throw immediately after such a problem (and that isn't so cool...)

So here is the trace illustrating the problem (the quotes around "test_sdb" is what stimulates it, but it seems to cope with it initially, but then poos...):

Select Expression = select * from "test_sdb" where value like "X1%"

*** SDB.select = {"items":"*","condition":"value","limit":0}

domainIndex records: {}

domain name not found

BoxUsage: 0.0050000000

/root/node_modules/redis-node/lib/client.js:278

        commandName = commandForReply.commandName;

                                     ^

TypeError: Cannot read property 'commandName' of undefined

    at Client.handleReply (/root/node_modules/redis-node/lib/client.js:278:38)

    at Client.emit (events.js:67:17)

    at Client.handleData (/root/node_modules/redis-node/lib/client.js:249:18)

    at Socket.emit (events.js:67:17)

    at TCP.onread (net.js:347:14)

Is there anything can be done to make this more robust?  (Sorry, js isn't really my bag...)

Thanks

Alan

[Rob Tweed]

Alan

Glad you figured out a way round the issue.

Unfortunately I don't do much with node-mdb any more, particularly since Amazon pretty much deprecated SimpleDB (though I realise it's still there).  I'm tied up these days with tighter integration of M databases with Node.js.

node-mdb is, of course, Open Source, so anyone can have a go at modifying it and fixing problems.  I really won't have free time to go in and research and fix the Select problem you've described - paid work gets priority I'm afraid.  If you're happy to pay for my time, then I can take a look however

Hope this helps

Rob

Alan

--
You received this message because you are subscribed to the Google Groups "M/DB Community Forum" group.
To unsubscribe from this group and stop receiving emails from it, send an email to mdb-community-f...@googlegroups.com.
To post to this group, send an email to mdb-commu...@googlegroups.com.
Visit this group at http://groups.google.com/group/mdb-community-forum?hl=en-GB.
For more options, visit https://groups.google.com/groups/opt_out.
 
 

--
Rob Tweed
Director, M/Gateway Developments Ltd
http://www.mgateway.com
------------------
EWD Mobile: Build mobile applications faster
http://www.mgateway.com/ewd.html

[Alan Pound]

Hi Rob

Thanks for the reply...  I understand what you mean about SDB - although Amazon haven't exactly deprecated it, but they have certainly "de-emphasised" it.  

It is a shame really, as provided your database needs are modest - less than the (stated) 10GB size, and less than the (completely opaque) write/delete performance, it is easy to use and very flexible.  

But I guess it doesn't really meet their overall scalability aims, and probably had customers giving them grief when they exceeded the (unstated) write performance limits.  Also, it really never was a first-class AWS citizen, as it has zero visibility through the AWS dashboard.

Yes, we had to move to dynamodb for our high performance needs (now that's a different set of challenges, and certainly not a general-purpose solution) - but we still use some SDB for the small stuff.

Anyway - thanks for your efforts in respect of MDB.  I'll admit I had some reservations initially, but I can see the underlying technology is sound, and I'm hopeful I can work through any node-mdb.js issues that I come across.  

All the best.

Alan