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Oracle SQL: Update a table with data from another table
...
This is called a correlated update
UPDATE table1 t1
SET (name, desc) = (SELECT t2.name, t2.desc
FROM table2 t2
WHERE t1.id = t2.id)
WHERE EXISTS (
SELECT 1
FROM table2 t2...
Why would one omit the close tag?
...e file (and possibly some other factors I don't want to bore you with).
Finally, many PHP frameworks including Symfony, Zend and Laravel (there is no mention of this in the coding guidelines but it follows the suit) and the PSR-2 standard (item 2.2) require omission of the closing tag. PHP manual it...
How to run a Python script in the background even after I logout SSH?
I have Python script bgservice.py and I want it to run all the time, because it is part of the web service I build. How can I make it run continuously even after I logout SSH?
...
How do I expand the output display to see more columns of a pandas DataFrame?
...: None] [currently: None]
: float or None
if set to a float value, all float values smaller then the given threshold
will be displayed as exactly 0 by repr and friends.
display.colheader_justify: [default: right] [currently: right]
: 'left'/'right'
Controls the justification ...
Comparing two dataframes and getting the differences
...df2, works only for dataframes with identical rows and columns. In fact, all dataframes axes are compared with _indexed_same method, and exception is raised if differences found, even in columns/indices order.
If I got you right, you want not to find changes, but symmetric difference. For that, o...
Download JSON object as a file from browser
...or without explicit clicking since I want to trigger the download automatically at some point from js.
JS solution (no HTML required):
function downloadObjectAsJson(exportObj, exportName){
var dataStr = "data:text/json;charset=utf-8," + encodeURIComponent(JSON.stringify(exportObj));
var ...
Are PHP Variables passed by value or by reference?
... function is changed, it does not get changed outside of the function). To allow a function to modify its arguments, they must be passed by reference.
To have an argument to a function always passed by reference, prepend an ampersand (&) to the argument name in the function definition.
&l...
腾讯Tencent开源框架介绍（持续更新） - 开源 & Github - 清泛网 - 专注C/C++及内核技术
...h>
#include <stdio.h>
#include <stdlib.h>
#include <queue>
#include "co_routine.h"
using namespace std;
/**
* 本实例是对条件变量的展示，其作用类似于pthread_cond_wait
*/
struct stTask_t
{
int id;
};
struct stEnv_t
{
stCoCond_t* cond;
queue<stTask_t*> task_queue...
Should I store entire objects, or pointers to objects in containers?
... storing pointers into vector can be efficient if used along with a custom allocator for the pointees. The custom allocator has to take care of the cache locality, for example using placement new (see en.wikipedia.org/wiki/Placement_syntax#Custom_allocators).
– amit
...
How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
...olumn, select just that column. in this case I'm using inplace=True to actually change the contents of df.
In [12]: df[1].fillna(0, inplace=True)
Out[12]:
0 0.000000
1 0.570994
2 0.000000
3 -0.229738
4 0.000000
Name: 1
In [13]: df
Out[13]:
0 1
0 NaN 0.0000...