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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. ...
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...
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?
...
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
...
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
...
onIabPurchaseFinished never called.
I've been trying to set up in-app billing for my first app, and have been using the android.test.purchased sku. The purchase come through, and I manage to get the SKU into my inventory, but, as the title says, onIabPurchaseFinished, is never called.
...
Git clone without .git directory
...st bit of history possible to get that repo.
The branch option is optional and if not specified would get master.
The second line will make your directory dirformynewrepo not a Git repository any more.
If you're doing recursive submodule clone, the depth and branch parameter don't apply to the submo...
How can I convert a PFX certificate file for use with Apache on a linux server?
...With OpenSSL you can convert pfx to Apache compatible format with next commands:
openssl pkcs12 -in domain.pfx -clcerts -nokeys -out domain.cer
openssl pkcs12 -in domain.pfx -nocerts -nodes -out domain.key
First command extracts public key to domain.cer.
Second command extracts private key to...
How to check if a string is a valid hex color representation?
...beginning
# -> a hash
[0-9A-F] -> any integer from 0 to 9 and any letter from A to F
{6} -> the previous group appears exactly 6 times
$ -> match end
i -> ignore case
If you need support for 3-character HEX codes, use the following:
/^#([0-9A-F]{...