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Max length for client ip address [duplicate]
...are 0-255, i.e., one byte). But then you would have to translate going in and out of the DB and that's messy.
IPv6 addresses are 128 bits (as opposed to 32 bits of IPv4 addresses). They are usually written as 8 groups of 4 hex digits separated by colons: 2001:0db8:85a3:0000:0000:8a2e:0370:7334. ...
Sort a text file by line length including spaces
...s wanted for lines of matching length. I've assumed that this is unwanted and suggested the use of -s (--stable) to prevent such lines being sorted against each other, and keep them in the relative order in which they occur in the input.
(Those who want more control of sorting these ties might loo...
Check if Key Exists in NameValueCollection
Is there a quick and simple way to check if a key exists in a NameValueCollection without looping through it?
12 Answers
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how to exclude null values in array_agg like in string_agg using postgres?
... non_canonical_users
FROM groups g
GROUP BY g.id
) s
Or, simpler and may be cheaper, using array_to_string which eliminates nulls:
SELECT
g.id,
array_to_string(
array_agg(CASE WHEN g.canonical = 'Y' THEN g.users ELSE NULL END)
, ','
) canonical_users,
array...
How do I read an attribute on a class at runtime?
...m trying to create a generic method that will read an attribute on a class and return that value at runtime. How do would I do this?
...
Convert Django Model object to dict with all of the fields intact
...ject to a dict with all of its fields? All ideally includes foreign keys and fields with editable=False .
12 Answers
...
Initializing a two dimensional std::vector
...std::vector::vector(count, value) constructor that accepts an initial size and a default value:
std::vector<std::vector<int> > fog(
A_NUMBER,
std::vector<int>(OTHER_NUMBER)); // Defaults to zero initial value
If a value other than zero, say 4 for example, was required to...
How to find the created date of a repository project on GitHub?
...
This worked on a live repo and also on a recently dead one too.
– Joe
Jan 23 '18 at 4:45
...
What is a handle in C++?
I have been told that a handle is sort of a pointer, but not, and that it allows you to keep a reference to an object, rather than the object itself. What is a more elaborate explanation?
...
decorators in the python standard lib (@deprecated specifically)
I need to mark routines as deprecated, but apparently there's no standard library decorator for deprecation. I am aware of recipes for it and the warnings module, but my question is: why is there no standard library decorator for this (common) task ?
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