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What rules does Pandas use to generate a view vs a copy?
I'm confused about the rules Pandas uses when deciding that a selection from a dataframe is a copy of the original dataframe, or a view on the original.
...
How can I change the table names when using ASP.NET Identity?
...atest (RTM) version of AspNet.Identity. When I create a new web project, I select "Individual User Accounts" for authentication. This creates the following tables:
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How can I configure my makefile for debug and release builds?
...lds.
Supports ...
separate project directories for specific builds
easy selection of a default target build
silent prep target to create directories needed for building the project
build-specific compiler configuration flags
GNU Make's natural method of determining if project requires a rebuild
p...
How do I time a method's execution in Java?
....stop());
The nice thing is that Stopwatch.toString() does a good job of selecting time units for the measurement. I.e. if the value is small, it'll output 38 ns, if it's long, it'll show 5m 3s
Even nicer:
Stopwatch timer = Stopwatch.createUnstarted();
for (...) {
timer.start();
methodToTr...
Recommendations of Python REST (web services) framework? [closed]
...e service's logic is implemented only once, and the correct representation selection (Accept header) + dispatch to the proper render function (or template) is done in a tidy, transparent way.
$ curl localhost:8080/x
<html><body>Hello, x!</body></html>
$ curl -H "Accept: app...
How to get a variable name as a string in PHP?
...bug_backtrace();
// read file
$file = file($bt[0]['file']);
// select exact print_var_name($varname) line
$src = $file[$bt[0]['line']-1];
// search pattern
$pat = '#(.*)'.__FUNCTION__.' *?\( *?(.*) *?\)(.*)#i';
// extract $varname from match no 2
$var = preg_replace...
What is the difference between varchar and nvarchar?
... NLS_CHARACTERSET option is set. You may be able to find it with the query SELECT value$ FROM sys.props$ WHERE name = 'NLS_CHARACTERSET'.
If your NLS_CHARACTERSET is a Unicode encoding like UTF8, great. Using VARCHAR and NVARCHAR are pretty much identical. Stop reading now, just go for it. Otherwis...
What database does Google use?
... with different time stamps. The time stamp allows for operations such as "select 'n' versions of this Web page" or "delete cells that are older than a specific date/time."
In order to manage the huge tables, Bigtable splits tables at row boundaries and saves them as tablets. A tablet is around 20...
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock'
...d_safe --skip-grant-tables &
Log into MySQL using root
mysql -uroot
Select the MySQL database to use
use mysql;
Reset the password
-- MySQL version < 5.7
update user set password=PASSWORD("mynewpassword") where User='root';
-- MySQL 5.7, mysql.user table "password" field -> "authent...
Path to Powershell.exe (v 2.0)
...
Here is one way...
(Get-Process powershell | select -First 1).Path
Here is possibly a better way, as it returns the first hit on the path, just like if you had ran Powershell from a command prompt...
(Get-Command powershell.exe).Definition
...