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E11000 duplicate key error index in mongodb mongoose
... null value.
In other words, a sparse index is ok with multiple documents all having null values.
sparse indexes
From comments:
Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old an...
How to find corresponding log files folder for a web site?
...
Ok, I've found this property - it's called "site id" and resides in "Advanced Properties" of the website.
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Doctrine - How to print out the real sql, not just the prepared statement?
...trine is not sending a "real SQL query" to the database server : it is actually using prepared statements, which means :
Sending the statement, for it to be prepared (this is what is returned by $query->getSql())
And, then, sending the parameters (returned by $query->getParameters())
and exe...
How to host a Node.Js application in shared hosting [closed]
... Run the node app from PHP:
<?php
//Choose JS file to run
$file = 'node_modules/jt-js-sample/index.js';
//Spawn node server in the background and return its pid
$pid = exec('PORT=49999 node/bin/node ' . $file . ' >/dev/null 2>&1 & echo $!');
//Wait for node to start up
usleep(50000...
Moving average or running mean
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UPD: more efficient solutions have been proposed by Alleo and jasaarim.
You can use np.convolve for that:
np.convolve(x, np.ones((N,))/N, mode='valid')
Explanation
The running mean is a case of the mathematical operation of convolution. For the running mean, you slide...
通过FastCGI Cache实现服务降级 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...，架构图如下：
Degradation
实现的关键点在于通过error_page处理异常，并且完成服务降级：
limit_conn_zone $server_name zone=perserver:1m;
error_page 500 502 503 504 = @failover;
fastcgi_cache_path
/tmp
levels=1:2
keys_zone=failover:100m
i...
Getting time elapsed in Objective-C
...er to use Apple's function CACurrentMediaTime!
I also benchmarked the mach_timebase_info call and it takes approximately 19ns on my iPhone 6, so I removed the (not threadsafe) code which was caching the output of that call.
#include <mach/mach.h>
#include <mach/mach_time.h>
uint64_t g...
Save bitmap to location
...my image in canvas it is very small. any reason?
– AZ_
Mar 18 '11 at 13:24
3
@Aizaz This will not...
What does (function($) {})(jQuery); mean?
I am just starting out with writing jQuery plugins. I wrote three small plugins but I have been simply copying the line into all my plugins without actually knowing what it means. Can someone tell me a little more about these? Perhaps an explanation will come in handy someday when writing a framewor...
Which comment style should I use in batch files?
...his is a comment, the caret is ignored^
echo This line is printed
REM This_is_a_comment_the_caret_appends_the_next_line^
echo This line is part of the remark
REM followed by some characters .:\/= works a bit different, it doesn't comment an ampersand, so you can use it as inline comment.
echo Fi...