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Insert new column into table in sqlite?
...AULT {defaultValue}; More important: (thinking about why you would want to order the columns..) use in every record action (like insert or add) always the column names, this way, you will never get mistakes somewheere in your code after altering the table.
– michel.iamit
...
What does middleware and app.use actually mean in Expressjs?
...example?, how can you pass in so many functions into app.get(...) and what order are they called?
– Tanner Summers
Mar 27 '18 at 15:20
2
...
PHP best way to MD5 multi-dimensional array?
.../Optionally make a copy of the array (if you want to preserve the original order)
$original = $array;
array_multisort($array);
$hash = md5(json_encode($array));
Edit: There's been some question as to whether reversing the order would produce the same results. So, I've done that (correctly) here:
...
How to change the order of DataFrame columns?
... + cols[:-1]
In [13]: cols
Out[13]: ['mean', 0L, 1L, 2L, 3L, 4L]
Then reorder the dataframe like this:
In [16]: df = df[cols] # OR df = df.ix[:, cols]
In [17]: df
Out[17]:
mean 0 1 2 3 4
0 0.445543 0.445598 0.173835 0.343415 0.682252 ...
Select SQL Server database size
... , RowNum = ROW_NUMBER() OVER (PARTITION BY s.database_name, s.[type] ORDER BY s.backup_finish_date DESC)
FROM msdb.dbo.backupset s
WHERE s.[type] IN ('D', 'L')
) f
WHERE f.RowNum = 1
GROUP BY f.database_name
) bu ON d.name = bu.database_name
ORDER BY t.total_size DE...
What is the difference between linear regression and logistic regression?
...nature. For instance, yes/no, true/false, red/green/blue,
1st/2nd/3rd/4th, etc.
Linear regression is used when your response variable is continuous. For instance, weight, height, number of hours, etc.
Equation
Linear regression gives an equation which is of the form Y = mX + C,
means equation w...
Why is using the rails default_scope often recommend against?
... of default_scope is when you want something to be sorted: default_scope { order(:name) }.
– user2985898
Aug 25 '16 at 9:33
...
Linux日志切分工具：Logrotate - 更多技术 - 清泛网 - 专注C/C++及内核技术
...绍
显而易见，Logrotate是基于CRON来运行的，其脚本是「/etc/cron.daily/logrotate」：
#!/bin/sh
/usr/sbin/logrotate /etc/logrotate.conf
EXITVALUE=$?
if [ $EXITVALUE != 0 ]; then
/usr/bin/logger -t logrotate "ALERT exited abnormally with [$EXITVALUE]"
fi
exit 0
实...
How to change Elasticsearch max memory size
...one of the above answers worked for me.
I tried changing ES_HEAP_SIZE in /etc/default/elasticsearch and in etc/init.d/elasticsearch, but when I ran ps aux | grep elasticsearch the output still showed:
/usr/bin/java -Xms2g -Xmx2g # aka 2G min and max ram
I had to make these changes in:
/etc/elas...
Encrypting & Decrypting a String in C# [duplicate]
...repended to the cipher text upon encryption and extracted from it again in order to perform the decryption. The result of this is that encrypting the exact same plaintext with the exact same password gives and entirely different ciphertext result each time.
The "strength" of using this comes from ...