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MySQL show current connection info
...e are MYSQL functions you can use. Like this one that resolves the user:
SELECT USER();
This will return something like root@localhost so you get the host and the user.
To get the current database run this statement:
SELECT DATABASE();
Other useful functions can be found here: http://dev.mys...
How to export data as CSV format from SQL Server using sqlcmd?
...
You can run something like this:
sqlcmd -S MyServer -d myDB -E -Q "select col1, col2, col3 from SomeTable"
-o "MyData.csv" -h-1 -s"," -w 700
-h-1 removes column name headers from the result
-s"," sets the column seperator to ,
-w 700 sets the row width to 700 chars (this will nee...
How to use NULL or empty string in SQL
...
Select *
From Table
Where (col is null or col = '')
Or
Select *
From Table
Where IsNull(col, '') = ''
share
|
improve t...
difference between socket programming and Http programming
...sponse.
Stream receiveStream = response.GetResponseStream ();
// Pipes the stream to a higher level stream reader with the required encoding format.
StreamReader readStream = new StreamReader (receiveStream, Encoding.UTF8);
Console.WriteLine ("Response stream received.");
Cons...
Convert data.frame column format from character to factor
...yr::mutate_if() to convert all character columns or dplyr::mutate_at() for select named character columns to factors:
library(dplyr)
# all character columns to factor:
df <- mutate_if(df, is.character, as.factor)
# select character columns 'char1', 'char2', etc. to factor:
df <- mutate_at(d...
How to color System.out.println output? [duplicate]
...7 | white |
| 39 | 49 | default |
+~~~~~~+~~~~~~+~~~~~~~~~~~+
Select Graphic Rendition (SGR)
SGR just allows you to change the text. Many of these do not work in certain terminals, so use these sparingly in production-level projects. However, they can be useful for making program outpu...
Do HTML WebSockets maintain an open connection for each client? Does this scale?
... limitation that is usually encountered is the maximum number of file descriptors (sockets consume file descriptors) that can be open simultaneously. This often defaults to 1024 but can easily be configured higher.
Ever tried configuring a web server to support tens of thousands of simultaneous AJA...
Modify table: How to change 'Allow Nulls' attribute from not null to allow null
...
I wrote this so I could edit all tables and columns to null at once:
select
case
when sc.max_length = '-1' and st.name in ('char','decimal','nvarchar','varchar')
then
'alter table [' + so.name + '] alter column [' + sc.name + '] ' + st.name + '(MAX) NULL'
when st.name in ('char','decimal','n...
Nginx 403 error: directory index of [folder] is forbidden
... rewrite ^/(.+)/$ /$1 permanent;
}
# pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
location ~ \.php$ {
fastcgi_split_path_info ^(.+\.php)(/.+)$;
# # NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini
# # With php5-fpm:
...
How to check if a particular service is running on Ubuntu
...
For Ubuntu (checked with 12.04)
You can get list of all services and select by color one of them with 'grep':
sudo service --status-all | grep postgres
Or you may use another way if you know correct name of service:
sudo service postgresql status
...