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This example shows how to create a prepared statement with an insert statement with parameters, set values to those parameters and then executing the statement. Connection connection = ... // connection created earlier try (PreparedStatement insert = connection.prepareStatement( "i...

In PaaS sites such as Heroku, it is usual to receive the database information as a single URL environment variable, instead of several parameters (host, port, user, password...). There is a module, dj_database_url which automatically extracts the DATABASE_URL environment variable to a Python dictio...

To connect to MySQL you need to use the MySQL Connector/J driver. You can download it from http://dev.mysql.com/downloads/connector/j/ or you can use Maven: <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version...

In order to include plots created with matplotlib in TeX documents, they should be saved as pdf or eps files. In this way, any text in the plot (including TeX formulae) is rendered as text in the final document. import matplotlib.pyplot as plt plt.rc(usetex=True) x = range(0, 10) y = [t**2 for t...

public class MyObject{ public DateTime? TestDate { get; set; } public Func<MyObject, bool> DateIsValid = myObject => myObject.TestDate.HasValue && myObject.TestDate > DateTime.Now; public void DoSomething(){ //We can do this: if(this.TestDate....

In many Excel applications, the VBA code takes actions directed at the workbook in which it's contained. You save that workbook with a ".xlsm" extension and the VBA macros only focus on the worksheets and data within. However, there are often times when you need to combine or merge data fr...

To create a project called helloworld run: stack new helloworld simple This will create a directory called helloworld with the files necessary for a Stack project.

Example uses of $(document).ready(): Attaching event handlers Attach jQuery event handlers $(document).ready(function() { $("button").click(function() { // Code for the click function }); }); Run jQuery code after the page structure is created jQuery(function($) ...

Step 1: Install the SDK You can install the SDK manually or via CocoaPods. The latter option is highly recommended. Put these lines in Podfile: target 'MyApp' do use_frameworks! pod 'FBSDKCoreKit' pod 'FBSDKLoginKit' pod 'FBSDKShareKit' end Run pod install in the terminal and op...

When building a webserver with Express it's often required to serve a combination of dynamic content and static files. For example, you may have index.html and script.js which are static files kept in the file system. It is common to use folder named 'public' to have static files. In this case th...

I/O in node is asynchronous, so interacting with the disk and network involves passing callbacks to functions. You might be tempted to write code that serves up a file from disk like this: var http = require('http'); var fs = require('fs'); var server = http.createServer(function (req, res) { ...

Example. It will be replacing the word email to a name in a text file index.txt with simple RegExp replace(/email/gim, 'name') var fs = require('fs'); fs.readFile('index.txt', 'utf-8', function(err, data) { if (err) throw err; var newValue = data.replace(/email/gim, 'name'); ...

app.js const readline = require('readline'); const fs = require('fs'); var file = 'path.to.file'; var linesCount = 0; var rl = readline.createInterface({ input: fs.createReadStream(file), output: process.stdout, terminal: false }); rl.on('line', function (line) { linesCo...

Hstore columns can be useful to store settings. They are available in PostgreSQL databases after you enabled the extension. class CreatePages < ActiveRecord::Migration[5.0] def change create_table :pages do |t| enable_extension 'hstore' unless extension_enabled?('hstore') t...

F# allow existing types to be extended with new static functions. type System.String with static member EqualsCaseInsensitive (a, b) = String.Equals(a, b, StringComparison.OrdinalIgnoreCase) This new function can be invoked like this: let x = String.EqualsCaseInsensitive("abc", &...

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil]; With an Identifier: Give the scene a Storyboard ID within the identity inspector of the storyboard. Instantiate in code: UIViewController *controller = [storyboard instantiateViewControllerWithIdentifi...

from struct import pack print(pack('I3c', 123, b'a', b'b', b'c')) # b'{\x00\x00\x00abc'

from struct import unpack print(unpack('I3c', b'{\x00\x00\x00abc')) # (123, b'a', b'b', b'c')

Download and install Xamarin Studio Community. Open Xamarin Studio. Click File → New → Solution. Click .NET → Console Project and choose C#. Click Next to proceed. Enter the Project Name and Browse... for a Location to Save and then click Create. The newly created project w...

Creating the JFrame Creating a window is easy. You just have to create a JFrame. JFrame frame = new JFrame(); Titling the Window You may wish to give your window a title. You can so do by passing a string when creating the JFrame, or by calling frame.setTitle(String title). JFrame frame = new...