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How much faster is Redis than mongoDB?
...is()
mongo = Connection().test
collection = mongo['test']
collection.ensure_index('key', unique=True)
def mongo_set(data):
for k, v in data.iteritems():
collection.insert({'key': k, 'value': v})
def mongo_get(data):
for k in data.iterkeys():
val = collection.find_one({'key'...
How to change the name of a Django app?
...ls.py , 'manage.py' , and settings.py files.
Edit the database table django_content_type with the following command: UPDATE django_content_type SET app_label='<NewAppName>' WHERE app_label='<OldAppName>'
Also if you have models, you will have to rename the model tables. For postgres use...
How do I parallelize a simple Python loop?
...tead:
pool = multiprocessing.Pool(4)
out1, out2, out3 = zip(*pool.map(calc_stuff, range(0, 10 * offset, offset)))
Note that this won't work in the interactive interpreter.
To avoid the usual FUD around the GIL: There wouldn't be any advantage to using threads for this example anyway. You want t...
define() vs. const
... a static scalar (number, string or other constant like true, false, null, __FILE__), whereas define() takes any expression. Since PHP 5.6 constant expressions are allowed in const as well:
const BIT_5 = 1 << 5; // Valid since PHP 5.6 and invalid previously
define('BIT_5', 1 << 5); /...
Best way to select random rows PostgreSQL
...ery:
SELECT count(*) AS ct -- optional
, min(id) AS min_id
, max(id) AS max_id
, max(id) - min(id) AS id_span
FROM big;
The only possibly expensive part is the count(*) (for huge tables). Given above specifications, you don't need it. An estimate will do just fine,...
Is there a typical state machine implementation pattern?
... use a table driven approach for most state machines:
typedef enum { STATE_INITIAL, STATE_FOO, STATE_BAR, NUM_STATES } state_t;
typedef struct instance_data instance_data_t;
typedef state_t state_func_t( instance_data_t *data );
state_t do_state_initial( instance_data_t *data );
state_t do_state_f...
App Inventor 2 数据可视化教程 - 折线图/曲线图/实时数据绘图 · App Inventor 2 中文网
...线图）
积木块：
// 全局变量
global x计数 = 0
when 按钮_开始.Click() {
计时器1.TimerEnabled = true
二维图表数据1.Clear()
}
when 计时器1.Timer() {
global x计数 = x计数 + 1
global 随机值 = randomInteger(1, 100)
二维图表数据1.AddEntry(x计数, 随...
Converting a string to a date in JavaScript
...
function stringToDate(_date,_format,_delimiter)
{
var formatLowerCase=_format.toLowerCase();
var formatItems=formatLowerCase.split(_delimiter);
var dateItems=_date.split(_delimiter);
var monthIndex=f...
Google maps API V3 - multiple markers on exact same spot
...nt.
google.maps.event.trigger(markerClusterer, 'clusterclick', this.cluster_);
var zoom = this.map_.getZoom();
var maxZoom = markerClusterer.getMaxZoom();
// if we have reached the maxZoom and there is more than 1 marker in this cluster
// use our onClick method to popup a list of options
if (zoom ...
What is the difference between AF_INET and PF_INET in socket programming?
What is the difference between AF_INET and PF_INET in socket programming?
7 Answers
7
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