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How to 'bulk update' with Django?
...ings like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelClass.save method (so if you have some logic inside it won't be triggered).
No django signals will be emitte...
To ARC or not to ARC? What are the pros and cons? [closed]
...t has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables, inline functions, etc.)
OK, now I will...
Real world use cases of bitwise operators [closed]
...checksums, parity, stop bits, flow control algorithms, and so on, which usually depend on the logic values of individual bytes as opposed to numeric values, since the medium may only be capable of transmitting one bit at a time.
Compression, Encryption
Both of these are heavily dependent on bitwise ...
Why would I use Scala/Lift over Java/Spring? [closed]
...over it. From my perspective and experience, Java Annotations and Spring really minimizes the amount of coding that you have to do for an application. Does Scala/Lift improve upon that?
...
Difference between std::result_of and decltype
...
result_of was introduced in Boost, and then included in TR1, and finally in C++0x. Therefore result_of has an advantage that is backward-compatible (with a suitable library).
decltype is an entirely new thing in C++0x, does not restrict only to return type of a function, and is a language fe...
Android: failed to convert @drawable/picture into a drawable
In my drawable folder I have a few images and they all reference perfect, but when I try and add any more images with the exact same size in the same folder, and try to reference it, is flags up an error "Failed to convert @drawable/picture into a drawable" . I have tried the same image with a diff...
How do you find the row count for all your tables in Postgres
...h quote_ident or with the more modern format() function with its %I format string. Otherwise some malicious person may name their table tablename;DROP TABLE other_table which is perfectly valid as a table name.
Even without the SQL injection and funny characters problems, table name may exist in var...
What is the closest thing Windows has to fork()?
I guess the question says it all.
13 Answers
13
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angularjs directive call function specified in attribute and pass an argument to it
...({
is: 'search',
properties: {
text: {
type: String,
notify: true
},
},
regularSearch: function(e) {
console.log(this.range);
this.fire('complete', {'text': this.text});
},
listeners: {
'button.click': 'regularSearch',
...
Cron job every three days
...
The answer is not correct because neither suggestion actually runs the job every 3 days. 0 0 */3 * * means run on the 1st, 4th, 7th, etc. (*/3 means 1-31/3 means 1,4,7...31) so the gap will be smaller at the end of the month. (It'll run 2 days in a row if the previous month had 3...