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Static variables and methods are not part of an instance, There will always be a single copy of that variable no matter how many objects you create of a particular class. For example you might want to have an immutable list of constants, it would be a good idea to keep it static and initialize it j...

Check existing partitions on Schema SELECT * FROM user_tab_partitions;

A string resource provides text strings for your application with optional text styling and formatting. There are three types of resources that can provide your application with strings: String XML resource that provides a single string. Syntax: <?xml version="1.0" encoding="...

Use the yum command to manage packages in Enterprise Linux-based operating systems: yum install php This installs a minimal install of PHP including some common features. If you need additional modules, you will need to install them separately. Once again, you can use yum to search for these pac...

Examples of monotonic predicates are: unification with (=)/2 or unify_with_occurs_check/2 dif/2, expressing disequality of terms CLP(FD) constraints like (#=)/2 and (#>)/2, using a monotonic execution mode. Prolog predicates that only use monotonic goals are themselves monotonic. Monoton...

Sometimes what you have is a list, but the command you want to pass the items in the list to demands to get each item as a separate argument. For instance: the winfo children command returns a list of windows, but the destroy command will only take a sequence of window name arguments. set alpha [wi...

It is deemed best practice to always use Option Explicit in VBA as it forces the developer to declare all their variables before use. This has other benefits too, such as auto-capitalization for declared variable names and IntelliSense. Option Explicit Sub OptionExplicit() Dim a As Integer ...

Option Compare Binary Binary comparison makes all checks for string equality within a module/class case sensitive. Technically, with this option, string comparisons are performed using sort order of the binary representations of each character. A < B < E < Z < a < b < e < z ...

The nix crate provides an UNIX Rust API to handle signals, however it requires using unsafe rust so you should be careful. use nix::sys::signal; extern fn handle_sigint(_:i32) { // Be careful here... } fn main() { let sig_action = signal::SigAction::new(handle_sigint, ...

This method behaves as a combination of TryParse and ParseExact: It allows custom format(s) to be specified, and returns a Boolean result indicating success or failure rather than throwing an exception if the parse fails. TryParseExact(string, string, IFormatProvider, DateTimeStyles, out DateTime) ...

Enable and configure the experimental Gradle plugin to improve AndroidStudio's NDK support. Check that you fulfill the following requirements: Gradle 2.10 (for this example) Android NDK r10 or later Android SDK with build tools v19.0.0 or later Configure MyApp/build.gradle file Edit the dep...

HTML: <div id="title"> <h1 data-content="HOVER">HOVER</h1> </div> CSS: *{margin:0;padding:0;} html,body{height:100%;width:100%;overflow:hidden;background:#0099CC;} #title{ position:absolute; top:50%; left:50%; transform:translate(-50%,-...

SUB function allows to substitute text inside awk sub(regexp, replacement, target) where regexp could be a full regular expression $ cat file AAAAA BBBB CCCC DDDD EEEE FFFF GGGG $ awk '{sub("AAA","XXX", $0); print}' file XXXAA BBBB CCCC DDDD EEEE FFFF GGGG ...

(This is a request for a good example that shows how to construct a SELECT using CONCAT, then prepare+execute it. Please emphasize the use of @variables versus DECLAREd variables -- it makes a big difference, and it is something that novices (include myself) stumble over.)

Enabled directory index means that if someone access to any folder which don't contains index.php , index.html, index.htm or any other default file defined in DirectoryIndex in apache configuration then all files in that folder will be listed in browser if you try to visit that page. Often director...

Configuring your environment RabbitMQ looks for an set of environment variables in /etc/rabbitmq/rabbitmq-env.conf. If it does not exist, it assumes default values. All values in rabbitmq-env.conf get exported to the environment the RabbitMQ server runs in with a RABBITMQ_ prefix; this prefix is no...

Using the document-ready event can have small performance drawbacks, with delayed execution of up to ~300ms. Sometimes the same behavior can be achieved by execution of code just before the closing </body> tag: <body> <span id="greeting"></span> world! <sc...

Express is based on Connect, which is what provides the middleware functionality of Express. To understand what connect is, you can see that it provides the basic app structure that you use when you use express const connect = require('connect') const app = connect() app.listen(3000) This wi...

Use quasiquotes to create a Tree in a macro. object macro { def addCreationDate(): java.util.Date = macro impl.addCreationDate } object impl { def addCreationDate(c: Context)(): c.Expr[java.util.Date] = { import c.universe._ val date = q"new java.util.Date()" // this...

The macro() function allows you to add new functionality to Illuminate\Support\Collection objects Usage: Collection::macro("macro_name", function ($parameters) { // Your macro }); For example: Collection::macro('uppercase', function () { return $this->map(function ($i...