This is a very simple question, and maybe the man himself can provide insight on this :)
Does anyone know the pseudocode behind how Fog Creek does database schema management?
I'm running into an issue and I'm trying to figure out if I'm handling it right... I have a module that runs each time someone spins up their site and examines their database to make sure that they have the right changes in place. if they are missing changes, then the script makes the required changes.
My issue is that I was trying to tie it to the session_start portion of the Global.asax, but it seems to be rather flaky at times, and I'm trying to come up with a better scenario.
For reference, I'm trying to run 1 x web application that can respond to any number of hosts, where the host maps via a metabase to find out what database it belongs to and then makes the necessary connections.
You might have more luck asking this on http://fogbugz.stackexchange.com/
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I'm building a vClould client application via the REST APIs, however, the documentation is inconsistent an in some cases just wrong and misleading.
All I really need is a solid debug tool or even a log file. Any recommendations?
You already mentioned you have access to the message stream, which is one of the first steps. Typically if I'm using the Apache HttpClient/HttpComponents I'll go increase the log level so it logs the full HTTP requests.
My next step is usually to cheat and to log into vCD as a system administrator and see what's going on. When vCD was designed there was a very deliberate decision to not reveal infrastructure level problems to tenants of the cloud (normal org users or org admins), as that would break the cloud abstraction. Sadly, that means as an org-level user you're often going to get "contact your cloud admin" error responses. We are aware that this isn't ideal and try to find ways to make it better when we can (IIRC the new 5.5 release that was announced last month does have some improvements in that area).
The last step is usually to cheat even more and to look at the server side logs (vcloud-container-debug.log, specifically). That usually gives me a better clue as to what went wrong. Of course, you may be unlucky and not have access to the vCD cell machine.
My workaround in the latter two cases is to try the operations via the vCD UI and see (1) if they work as expected and (2) if they do, to check the system state via the API and see if I'm sending the wrong request payloads, etc. because the doc or schema reference may not have been clear enough.
In regards to the documentation, please use the feedback links () found on individual doc pages to let us know! Our technical writer reviews all the feedback and tries to address them.
My final suggestion is that you might want to post API questions to the vCloud API community forum VMware has. There are a number of experts (both users and VMware employees) that monitor it and respond to questions.
There is a process in our company built by a long-departed dev that pulls data from a cube stored in a MS SQL Analysis Server (which I typically access via Management Studio). The overall process almost never fails and is refreshed several times a day. However, there appear to be some bugs in the calculations that has been handed to me to investigate and fix.
Unfortunately, I knew nothing about cubes when this was handed to me, was not part of the original development process, and generic web tutorials don't seem to quite apply to whatever I'm looking at. On the plus side, trial and error has taught me enough that I can ask a few questions.
The bug is definitely in the calculations. But I obviously don't want to test in Production and I also don't want to make changes without a proper backup (that I know how to revert).
Is there a way to export the whole Analysis db to a .SLN file and open it in VS?
Should I instead use Script Cube as->Create to, change the cube name, and execute to make a copy?
If I'm later asked to add new dimensions or need to edit the data source, what's the best way to do this?
Any other tips?
You can create a Visual Studio project based on an existing cube. This will get everything in a project so you can investigate the calculations, make the necessary changes, deploy to a test environment, and check everything out before deploying to production. Don't forget to check the project into source control ;-)
I'm stumped and need some ideas on how to do this or even whether it can be done at all.
I have a client who would like to build a website tailored to English-speaking travelers in a specific country (Thailand, in this case). The different modes of transportation (bus & train) have good web sites for providing their respective information. And both are very static in terms of the data they present (the schedules rarely change). Here's one of the sites I would need to get info from: train schedules The client wants to provide users the ability to search for a beginning and end location and determine, using the external website's information, how they can best get there, being provided a route with schedule times for the different modes of chosen transport.
Now, in my limited experience, I would think the way to do that would be to retrieve the original schedule info from the external site's server (via API or some other means) and retain the info in a database, which can be queried as needed. Our first thought was to contact the respective authorities to determine how/if this can be done, but this has proven to be problematic due to the language barrier, mainly.
My client suggested what is basically "screen scraping", but that sounds like it would be complicated at best, downloading the web page(s) and filtering through the HTML for relevant/necessary data to put into the database. My worry is that the info on these mainly static sites is so static, that the data isn't even kept in a database to build the page and the web page itself is updated (hard-coded) when something changes.
I could really use some help and suggestions here. Thanks!
Screen scraping is always problematic IMO as you are at the mercy of the person who wrote the page. If the content is static, then I think it would be easier to copy the data manually to your database. If you wanted to keep up to date with changes, you could then snapshot the page when you transcribe the info and run a job to periodically check whether the page has changed from the snapshot. When it does, it sends an email for you to update it.
The above method could also be used in conjunction with some sort of screen scaper which could fall back to a manual process if the page changes too drastically.
Ultimately, it is a case of how much effort (cost) is your client willing to bear for accuracy
I have done this for the following site: http://www.buscatchers.com/ so it's definitely more than doable! A key feature of a web scraping solution for travel sites is that it must send you emails if anything went wrong during the scraping process. On the site, I use a two day window so that I have two days to fix the code if the design changes. Only once or twice have I had to change my code, and it's very easy to do.
As for some examples. There is some simplified source code here: http://www.buscatchers.com/about/guide. The full source code for the project is here: https://github.com/nicodjimenez/bus_catchers. This should give you some ideas on how to get started.
I can tell that the data is dynamic, it's to well structured. It's not hard for someone who is familiar with xpath to scrape this site.
Last night one of our SQL servers developed some major problems and after a colleague stopped, started, and all the usual things it started checking and rebuilding databases and is now running an extended stored procedure called "xp_qv".
The internet seems to be very short of information on what this procedure does or anythign like that so I was hoping somebody here might be able to help.
I should add that I assume it is meant to be running so the question isn't "Can I stop it" or anything like that, its just curiosity in what it is doing in the hope that it will help determine how long before things are usable again...
This is the only information I could find..
xp_qv, hosted in xpsqlbot.dll is a
wrapper around functionality in
sqlboot.dll, which returns information
about the SKU type, licensing etc It
is not documented that is why you can
not find a reference.
I need to learn more about creating setup projects from within Visual Studio to support the following scenario:
When the user starts the setup, he needs to choose between the parts that he wants to set up. The setup should offer to install three web services, one web site and maybe even run some SQL scripts to install/update the database.
During installation, the user will need to tell where he wants the sites/services to be installed within IIS. He also needs to specify the database connection which is used within the services/sites and to update the database. And there will probably be a few other wishes too. It should also support an uninstall of the site and services, but the database can continue to exist.
Is this even possible with the Setup projects that Visual Studio creates? If not, no worries. I don't need an alternative solution! I just need to know if this is possible before trying myself and discovering it's not possible after weeks of trying... This is for an internal project and I want to make life easier for the administrators who need to install/upgrade these sites/ services every time when there's an update. (About once every two weeks.)
Stay well away from vdproj stuff and move to WiX ASAP (As you'll see me being advised in questions I asked here). For a start, flexibility around where to put the IIS apps is seriously limited (you get one virtual dir and the user can only choose the name, you cant have multiple instances).
The other side of this is of course that the vdproj stuff is an 80% solution. Ultimately you can add as many custom steps as you like, and they can pop up dialogs and whatever they like. There's no reason why a custom step cant do all the things you want.
I just know that I once thought like you, and looking back wish someone had grabbed me by the scruff of the neck and said, just use the proper stuff - even if it seems a little harder initially. There is a conversion tool that will suck in your vdproj and spit you out a WiX.
By all means, try wizarding up what you need and seeing if it works - most of the stuff is pretty searchable - just know when to call it quits.