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os.chmod(path, mode) where mode is the desired permission, in octal.

Create a DATABASE. Note that the shortened word SCHEMA can be used as a synonym. CREATE DATABASE Baseball; -- creates a database named Baseball If the database already exists, Error 1007 is returned. To get around this error, try: CREATE DATABASE IF NOT EXISTS Baseball; Similarly, DROP DATA...

iPhone OS 1 First iteration of Apple's touch-centric mobile operating system. No official name is given on its initial release; Apple marketing literature simply stated the iPhone runs a version of Apple's desktop operating system, OS X.On March 6, 2008, with the release of the iPhone software deve...

A lambda closure is created when a lambda expression references the variables of an enclosing scope (global or local). The rules for doing this are the same as those for inline methods and anonymous classes. Local variables from an enclosing scope that are used within a lambda have to be final. Wit...

All constructors in Java must make a call to the Object constructor. This is done with the call super(). This has to be the first line in a constructor. The reason for this is so that the object can actually be created on the heap before any additional initialization is performed. If you do not spe...

To improve performance one might want to add indexes to columns ALTER TABLE TABLE_NAME ADD INDEX `index_name` (`column_name`) altering to add composite (multiple column) indexes ALTER TABLE TABLE_NAME ADD INDEX `index_name` (`col1`,`col2`)

Middleware (also called pre and post hooks) are functions which are passed control during execution of asynchronous functions. Middleware is specified on the schema level and is useful for writing plugins. Mongoose 4.0 has 2 types of middleware: document middleware and query middleware. Document mid...

Arrays can be compared for equality with the aptly named isEqualToArray: method, which returns YES when both arrays have the same number of elements and every pair pass an isEqual: comparison. NSArray *germanMakes = @[@"Mercedes-Benz", @"BMW", @"Porsche", ...

The AUROC is one of the most commonly used metric to evaluate a classifier's performances. This section explains how to compute it. AUC (Area Under the Curve) is used most of the time to mean AUROC, which is a bad practice as AUC is ambiguous (could be any curve) while AUROC is not. Overview – Abb...

SELECT is used to retrieve rows of data from a table. You can specify which columns will be retrieved: SELECT Name, Position FROM Employees; Or just use * to get all columns: SELECT * FROM Employees;

This query will return all columns from the table sales where the values in the column amount is greater than 10 and the data in the region column in "US". SELECT * FROM sales WHERE amount > 10 AND region = "US" You can use regular expressions to select the columns you wan...

Oozie is developed on a client-server architecture. Oozie server is a Java web application that runs Java servlet container within an embedded Apache Tomcat. Oozie provides three different type of clients to interact with the Oozie server: Command Line, Java Client API and HTTP REST API. Oozie serv...

A compound literal is an unnamed object which is created in the scope where is defined. The concept was first introduced in C99 standard. An example for compound literal is Examples from C standard, C11-§6.5.2.5/9: int *p = (int [2]){ 2, 4 }; p is initialized to the address of the first ele...

The normal way to create an array of numbers: numbers = [1, 2, 3, 4, 5] Range objects can be used extensively to create an array of numbers: numbers = Array(1..10) # => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] numbers = (1..10).to_a # => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] #step and #map methods...

A common workflow for using Git LFS is to declare which files are intercepted through a rules-based system, just like .gitignore files. Much of time, wildcards are used to pick certain file-types to blanket track. e.g. git lfs track "*.psd" When a file matching the above pattern is adde...

Suggested max len First, I will mention some common strings that are always hex, or otherwise limited to ASCII. For these, you should specify CHARACTER SET ascii (latin1 is ok) so that it will not waste space: UUID CHAR(36) CHARACTER SET ascii -- or pack into BINARY(16) country_code CHAR(2) CHAR...

Any size of INT may be used for AUTO_INCREMENT. UNSIGNED is always appropriate. Keep in mind that certain operations "burn" AUTO_INCREMENT ids. This could lead to an unexpected gap. Examples: INSERT IGNORE and REPLACE. They may preallocate an id before realizing that it won't be need...

There is already a separate entry for "FLOAT, DOUBLE, and DECIMAL" and "ENUM". A single page on datatypes is likely to be unwieldy -- I suggest "Field types" (or should it be called "Datatypes"?) be an overview, then split into these topic pages: INTs FLO...

String concatenation is when you combine two or more strings into a single string variable. String concatenation is performed with the & symbol. Dim one As String = "Hello " Dim two As String = "there" Dim result As String = one & two Non-string values will be conv...

7.0 OrElse Sub Main() Dim elements As List(Of Integer) = Nothing Dim average As Double = AverageElementsOrElse(elements) Console.WriteLine(average) ' Writes 0 to Console Try 'Throws ArgumentNullException average = AverageElementsOr(elements) Catch ex ...