python - How to get the distinct value of one of my models in Google App Engine -

-

I have a model, below, and I would like to get all the specific field values ​​< / Code> 

  class tutorial SQL equals  select from different areas tutorial (db.Model): path = db.StringProperty () area = db.StringProperty () sub_area = db .StringProperty () title = db.StringProperty () content = db.BlobProperty () Rating = db.RatingProperty () publishedDate = db.DateTimeProperty () published = db.BooleanProperty ()

I know that I can do Python 

  a = ['google.com', 'la Vjornl dot com ',' Laivjornl dot com ',' google.com ',' Stakvovrflo. Com '] B = set (A) B & gt; & Gt; & Gt; Set (['livejournal.com', 'google.com', 'stackoverflow.com'])

But I need to take the objects in the field out of query to another list And it is going against the list (it seems very inefficient) and if I have a separate item which is in the 1001 position in the datasheet, then I will not see it due to the fetch limit of 1000.

I will find all the different values ​​in the area in my datasheet to dump on the screen in the form of links.

Datastore can not do it in the same query to one of your datastore request always results from an index Gives a consistent block of, and an index always consists of all types of institutions, which are ordered according to the order specified. There is no way to leave items due to duplicate values ​​in a field.

An alternative introduced a new entity type that represents a "region for example to restructure your data" to add a tutorial to make related "zone" if it does not already exist , and if the "tutorial" there is still no tutorial with "area", so Tutorl delete each field that removing the "field" number of tutorials that area Micro stores, so it is pretty much can not be serious (though relevant factors with transactions etc. feel really good). I hope the key area of ​​the unit can be based on the string, which means that you can always look for the regional institutions rather than the main lookup instead of the query.

Another option is to use a queued work or a cron job to periodically create a list of all areas, if it is needed, on many requests, deposits, and the results are either datasheet or Put in the memkesh. This would mean that the list of areas can temporarily be out of time (or if there are continuous changes, it can never be fully), which can not be acceptable for you or not .

Finally, if there are a lot of areas in comparison to the tutorials, then you can fly by requesting tutorial (sorted by area) first, then the first tutorial is requested whose area is the area of ​​the first area More than, and so on. But this requires a request for each specific area, so there is no possibility of it being fast.


Comments

Post a Comment

Popular posts from this blog

c# - ListView onScroll event -

-
I am programming a simple C # application, and I need a Scallow event on the list view. So I inherited the original ListView class created in ListviewEx witch. I found out how to locate the scroll message from WinAPI and I modified the WndProc method. Now I have this WndProc: protected override zero WndProc (Ref message message) {base.WndProc (Ref I); If (m.msg == WM_VSCROLL) {onScroll (This, New EventArgs ()); }} But the problem is, I do not know how to know about scrolling information. This data should be in wParam, but there is a LOWORD macro ++ like in C in C # and I switch to find the criteria like SB_ below, SB_ENDSCROLL, SB_PAGEUP etc. there any way Need to change the LOWORD macro from C #? Or any other way to find the necessary parameters about scrolling? You can define the WParam constants as the following: Private const int WM_HSCROLL = 0x114; Private Constant WM_VSCROLL = 0x115; Private contact int SBHOZZ = 0; Private Consultant SB_VERT = 1; Private Con...
Read more

PHP - get image from byte array -

-
I am trying to create a back-end for my mobile application. I am sending the content of an image in the body of the HTTP request (output stream) as a byte array, I want to read this stream of bytes in PHP scripts and take back an image. Can anyone tell me how can I do this? Thank you. You can obtain the request body $ body = Reading from file_get_contents ('php: // input'); What you do with that data Depending on you, you can write the data in a file as you mentioned that this is image data, you can drop the data into the object can do. Another option is to use and load the image.
Read more

Linux Terminal Problem with Non-Canonical Terminal I/O app -

-
I have a small app written in C to run on Linux. Part of the app accepts user-input from keyboard , And it uses non-canonical terminal mode so that it can respond to each keystroke. The section of the code that accepts input is a simple task that is called repeatedly in the loop: char get_input () {char C = 0; Int res = reading (input_tamille, & amp; c, 1); If (RSS == 0) 0 returns; If (res == -1) {/ * snip error handling * /} return c; } It reads a letter from the terminal if there is no input within a given time limit, (c_cc [VTIME] value in the vocabulary structure), read () 0 And get_input () is called again It all works very well, I have recently discovered that if you run this app in a terminal window, and then the app Close the terminal window without ending, the app will not exit Received, but CPU intensive launches into an infinite loop, where the read () returns 0 without waiting continued. So how can I get out of the apple if it runs from the terminal win...
Read more