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How do you use variables in a simple PostgreSQL script?
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This doesn't answer the question at all. In MS SQL you can define a var in a query and use it right there, in the same tool. I don't get why people keep proposing this as an answer, in every version of this question.
– stone
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How to call a parent class function from derived class function?
...disambiguate it by adding the base class's name followed by two colons base_class::foo(...). You should note that unlike Java and C#, C++ does not have a keyword for "the base class" (super or base) since C++ supports multiple inheritance which may lead to ambiguity.
class left {
public:
void f...
JavaScript object: access variable property by name as string [duplicate]
...racket notation.
If you NEED a function for it, here it is:
function read_prop(obj, prop) {
return obj[prop];
}
To answer some of the comments below that aren't directly related to the original question, nested objects can be referenced through multiple brackets. If you have a nested objec...
Linux command to print directory structure in the form of a tree
... /proc
|-- fd
| `-- 3 -> /proc/15589/fd
|-- fdinfo
|-- net
| |-- dev_snmp6
| |-- netfilter
| |-- rpc
| | |-- auth.rpcsec.context
| | |-- auth.rpcsec.init
| | |-- auth.unix.gid
| | |-- auth.unix.ip
| | |-- nfs4.idtoname
| | |-- nfs4.nametoid
| | |-- nfsd.export
...
Linux环境离线安装docker&docker-compose - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
Linux环境离线安装docker&docker-composelinux_docker_install一、docker离线安装1、下载docker离线安装包下载最新版本的 docker （或者选择自己想要安装的版本）到本地。1）docker下载地址：Docker版本下载 ||Docker-compose版本下载备注...
一、docker...
Location of my.cnf file on macOS
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This thread on the MySQL forum says:
By default, the OS X installation does not use a my.cnf, and MySQL just uses the default values. To set up your own my.cnf, you could just create a file straight in /etc.
OS X provides example configuration files at /usr/local/mysql/support-files/...
How to Unit test with different settings in Django?
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EDIT: This answer applies if you want to change settings for a small number of specific tests.
Since Django 1.4, there are ways to override settings during tests:
https://docs.djangoproject.com/en/dev/topics/testing/tools/#overriding-settings
TestCase will have a self.settings context ma...
Declaring an enum within a class
...uct Color
{
enum Type
{
Red, Green, Black
};
Type t_;
Color(Type t) : t_(t) {}
operator Type () const {return t_;}
private:
//prevent automatic conversion for any other built-in types such as bool, int, etc
template<typename T>
operator T () const;
};
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Best way to generate random file names in Python
...me
basename = "mylogfile"
suffix = datetime.datetime.now().strftime("%y%m%d_%H%M%S")
filename = "_".join([basename, suffix]) # e.g. 'mylogfile_120508_171442'
share
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improve this answer
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Proper SCSS Asset Structure in Rails
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The problem with CSS is, you do not want to automatically add all files.
The order of which your sheets are loaded and processed by the browser is essential. So you will always end up explicitly importing all your css.
As an example, lets say you have a normalize.css sheet, t...