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Heroku “psql: FATAL: remaining connection slots are reserved for non-replication superuser connectio
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You either need to increase the max_connections configuration setting or (probably better) use connection pooling to route a large number of user requests through a smaller connection pool.
https://wiki.postgresql.org/wiki/Number_Of_Database_Connections
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How do you use Mongoose without defining a schema?
...ere not specified in our schema do not get saved to the db.
Note: Do not set to false unless you have good reason.
var thingSchema = new Schema({..}, { strict: false });
var Thing = mongoose.model('Thing', thingSchema);
var thing = new Thing({ iAmNotInTheSchema: true });
thing.sav...
.append(), prepend(), .after() and .before()
...ert content, specified by the parameter, to the end of each element in the set of matched elements.
.after(): Insert content, specified by the parameter, after each element in the set of matched elements.
.prepend() vs .before()
prepend(): Insert content, specified by the parameter, to the...
Generating all permutations of a given string
...caching any algorithm that outputs permutation is o(n!) because the result set to the permutation question is factorial to the input.
– jeremyjjbrown
Jan 2 '13 at 2:26
9
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How do I check if there are duplicates in a flat list?
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Use set() to remove duplicates if all values are hashable:
>>> your_list = ['one', 'two', 'one']
>>> len(your_list) != len(set(your_list))
True
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How do I append text to a file?
...t; all data in the file will be destroyed. You can change this behavior by setting the noclobber variable in your .bashrc:
set -o noclobber
Now when you try to do echo "hello" > file.txt you will get a warning saying cannot overwrite existing file.
To force writing to the file you must now us...
How do I ignore the initial load when watching model changes in AngularJS?
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set a flag just before the initial load,
var initializing = true
and then when the first $watch fires, do
$scope.$watch('fieldcontainer', function() {
if (initializing) {
$timeout(function() { initializing = false...
How do I achieve the theoretical maximum of 4 FLOPs per cycle?
...,r7,r8,r9,rA,rB,rC,rD,rE,rF;
// Generate starting data.
r0 = _mm_set1_pd(x);
r1 = _mm_set1_pd(y);
r8 = _mm_set1_pd(-0.0);
r2 = _mm_xor_pd(r0,r8);
r3 = _mm_or_pd(r0,r8);
r4 = _mm_andnot_pd(r8,r0);
r5 = _mm_mul_pd(r1,_mm_set1_pd(0.37796447300922722721));
r6 = _m...
Removing non-repository files with git?
... files - except when the Git configuration variable clean.requireForce is set to true. If its set to false, then -ff is needed for cleaning diretories
– Adam
Dec 24 '16 at 8:47
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Django's SuspiciousOperation Invalid HTTP_HOST header
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If your ALLOWED_HOSTS is set correctly, then it is possible someone is probing your site for the vulnerability by spoofing the header.
There is discussion right now by the Django developers to change this from a 500 internal server error to a 400 r...