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How to pull a random record using Django's ORM?
...on't know about other databases).
order_by('?')[:N] will be translated to SELECT ... FROM ... WHERE ... ORDER BY RAND() LIMIT N query.
It means that for every row in table the RAND() function will be executed, then the whole table will be sorted according to value of this function and then first N...
Picking a random element from a set
... the buckets that make up the hashset, which allows us to more efficiently select a random elements. If random elements are necessary in Java, it might be worthwhile to define a custom hash set that allows the user to look under the hood. See [boost's docs][1] for a little more in this. [1] boos...
How can one pull the (private) data of one's own Android app?
...app
Your android device will ask you for permission to backup your data. Select "BACKUP MY DATA"
Wait a few moments.
The file backup will appear in the directory where you ran adb.
Now run:
dd if=backup bs=1 skip=24 | python -c "import zlib,sys;sys.stdout.write(zlib.decompress(sys.stdin.read()...
A weighted version of random.choice
...dom.choice (each element in the list has a different probability for being selected). This is what I came up with:
25 Answ...
How to get the data-id attribute?
...e info here">My Awesome Div</div>
JS
var myDiv = document.querySelector('#my-div');
myDiv.dataset.info // "some info here"
myDiv.dataset.otherInfo // "more info here"
Demo: http://html5demos.com/dataset
Full browser support list: http://caniuse.com/#feat=dataset
...
Multiline string literal in C#
... in front of a string to form a verbatim string literal:
string query = @"SELECT foo, bar
FROM table
WHERE id = 42";
You also do not have to escape special characters when you use this method, except for double quotes as shown in Jon Skeet's answer.
...
How to set a default value for an existing column
...able and found this way to check if it had been done already... IF EXISTS(SELECT * FROM information_schema.columns WHERE table_name='myTable' AND column_name='myColumn' AND Table_schema = 'myDBO' AND column_default IS NULL) BEGIN ALTER TABLE [myDBO].[myTable] ADD DEFAULT 0 FOR [myColumn] END
...
jQuery selector for inputs with square brackets in the name attribute
I'm trying to select this element which has square brackets in the name attribute:
5 Answers
...
nvarchar(max) vs NText
...was instant.
I ran the following to find all columns needing conversion:
SELECT concat('ALTER TABLE dbo.[', table_name, '] ALTER COLUMN [', column_name, '] VARCHAR(MAX)'), table_name, column_name
FROM information_schema.columns where data_type = 'TEXT' order by table_name, column_name
SELECT conc...
How to use ADB Shell when Multiple Devices are connected? Fails with “error: more than one device an
...showing a menu when there are multiple devices connected:
$ adb $(android-select-device) shell
1) 02783201431feeee device 3) emulator-5554
2) 3832380FA5F30000 device 4) emulator-5556
Select the device to use, <Q> to quit:
To avoid typing you can just create an alias that included the device...