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Chaining multiple filter() in Django, is this a bug?
...ay suspect. It is how the WHERE and JOIN is placed.
Example1 (same joined table) :
(example from https://docs.djangoproject.com/en/dev/topics/db/queries/#spanning-multi-valued-relationships)
Blog.objects.filter(entry__headline__contains='Lennon', entry__pub_date__year=2008)
This will give you ...
Is it safe to parse a /proc/ file?
...s even less consistent than that. It's atomic only within each row of the table. To see this, look at listening_get_next() in net/ipv4/tcp_ipv4.c and established_get_next() just below in the same file, and see the locks they take out on each entry in turn. I don't have repro code handy to demonst...
Speed up the loop operation in R
... much guessing you eliminate.
Next, consider optimized packages: The data.table package can produce massive speed gains where its use is possible, in data manipulation and in reading large amounts of data (fread).
Next, try for speed gains through more efficient means of calling R:
Compile your...
What do the terms “CPU bound” and “I/O bound” mean?
... 363.64 166.67 2.18
MARK RESULTS TABLE
Mark Name MultiCore SingleCore Scaling
----------------------------------------------- ---------- ---------- ----------
CoreMark-PRO 18743....
Boolean operators && and ||
... this here: http://en.wikipedia.org/wiki/Short-circuit_evaluation From the table on that page you can see that && is equivalent to AndAlso in VB.NET, which I assume you are referring to.
share
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Remove duplicate values from JS array [duplicate]
... As this was reverted back to the original inArray solution by a reputable person, I am going to again mention: this solution is O(n^2), making it inefficient.
– Casey Kuball
Sep 21 '17 at 16:35
...
Error message “Forbidden You don't have permission to access / on this server” [closed]
...turn index_directory(r, d);
} else {
const char *index_names = apr_table_get(r->notes, "dir-index-names");
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01276)
"Cannot serve directory %s: No matching DirectoryIndex (%s) found, and "
...
How to overload functions in javascript?
...he second argument, it would have to be passed as null (or some other detectable value) instead and your code would detect that:
obj.query("firstArg", null, "thirdArg");
Here's a jQuery example of optional arguments. both arguments are optional and take on default values if not passed:
clone:...
Mimicking sets in JavaScript?
...nges over time, you can look at the line for Set in this ES6 compatibility table to see the current status for browser availability.
One advantage of the built-in Set object is that it doesn't coerce all keys to a string like the Object does so you can have both 5 and "5" as separate keys. And, you...
How to avoid null checking in Java?
...esn't understand them. So, in effect, the argument that the code is not portable may be invalid - if you use a system that supports and understands these annotations, you get the added benefit of stricter error checking, otherwise you get less of it but your code should still build fine, and the qua...