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Using current time in UTC as default value in PostgreSQL
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now() returns a value of type timestamp (just what we need) with your database's default time zone attached (e.g. 2018-11-11T12:07:22.3+05:00).
timezone('UTC', now()) turns our current time (of type timestamp with time zone) into the timezonless equivalent in UTC.
E.g., SELECT timestamp with time z...
Using Eloquent ORM in Laravel to perform search of database using LIKE
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If you need to frequently use LIKE, you can simplify the problem a bit. A custom method like ()...
Random row selection in Pandas dataframe
...e: As of Pandas v0.20.0, ix has been deprecated in favour of loc for label based indexing.
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记一次MongoDB性能问题 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...解决：
MongoDB按需自动生成数据文件：先是<DB>.0，大小是64M，然后是<DB>.1，大小翻番到128M，到了<DB>.5，大小翻番到2G，其后的数据文件就保持在2G大小。为了避免可能出现的问题，可以采用事先手动创建数据文件的策略：
#!/bin...
How to create a self-signed certificate for a domain name for development?
...et 2.0 SDK. On my server it's at:
C:\Program Files\Microsoft.Net\SDK\v2.0 64bit\Bin\makecert.exe
You can create a signing authority and store it in the LocalMachine certificates repository as follows (these commands must be run from an Administrator account or within an elevated command prompt):
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Any way to properly pretty-print ordered dictionaries?
... structures and lists just fine. I used the Mapping and Iterable abstract base classes from collections to handle just about anything.
I was aiming for almost yaml like output with concise python code, but didn't quite make it.
def format_structure(d, level=0):
x = ""
if isinstance(d, Map...
How do I clear a search box with an 'x' in bootstrap 3?
...s intent was to pass a truthy paramter to hide() to start off hidden/shown based on if the input has a value already. If that was the intent, he failed (hide always hides). It should be $(".clearer").toggle(!!$(this).prev('input').val());
– Jeff Shepler
Jun 10 ...
Stop pip from failing on single package when installing with requirements.txt
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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How do I get the function name inside a function in PHP?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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Where can I learn how to write C code to speed up slow R functions? [closed]
...can judge for yourself what you find more complicated, obfuscated, etc ... based on a few examples. This function creates a character vector using the C API:
SEXP foobar(){
SEXP ab;
PROTECT(ab = allocVector(STRSXP, 2));
SET_STRING_ELT( ab, 0, mkChar("foo") );
SET_STRING_ELT( ab, 1, mkChar(...