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Creating a managed table with partition and stored as a sequence file. The data format in the files is assumed to be field-delimited by Ctrl-A (^A) and row-delimited by newline. The below table is created in hive warehouse directory specified in value for the key hive.metastore.warehouse.dir in the ...

Creating a database in a particular location. If we dont specify any location for database its created in warehouse directory. CREATE DATABASE IF NOT EXISTS db_name COMMENT 'TEST DATABASE' LOCATION /PATH/HDFS/DATABASE/;

To change UI content in runtime, you can use Binding. When binded property is changed from the code, it will be displayed to the UI. <TextBlock Text="{Binding Title}"/> To notify UI about changes, property must raise PropertyChanged event from INotifyPropertyChanged interface or ...

In addition to the concept of column units, Bootstrap has different breakpoints or grid sizes known as tiers. The Bootstrap 3 grid has four (4) tiers to accomodate different screen (or viewport) widths. The Bootstrap 3 tiers are xs, sm, md, and lg. Bootstrap’s grid columns are identified by differen...

Processing tabular data with awk is very easy, provided that the input is correctly formatted. Most software producing tabular data use specific features of this family of formats, and awk programs processing tabular data are often specific to a data produced by a specific software. If a more gener...

Given a file using ; as a column delimiter. Permuting the first and the second column is accomplished by awk -F';' -v 'OFS=;' '{ swap = $2; $2 = $1; $1 = swap; print }'

Given a file using ; as a column delimiter. We compute the mean of the values in the second column with the following program, the provided input is the list of grades of a student group: awk -F';' '{ sum += $2 } END { print(sum / NR) }' <<EOF Alice;2 Victor;1 Barbara;1 Casper;4 Deborah;...

We assume a file using ; as a column delimiter. Selecting a specific set of columns only requires a print statement. For instance, the following program selects the columns 3, 4 and 7 from its input: awk -F';' -v 'OFS=;' '{ print $3, $4, $7 }' It is as usual possible to more carefully choose lin...

Given a file using ; as a column delimiter. We compute the median of the values in the second column with the following program, written for GNU awk. The provided input is the list of grades of a student group: gawk -F';' '{ sample[NR] = $2 } END { asort(sample); if(NR % 2 == 1) { p...

Use import to specify how a namespace from one library is used in the scope of another library. import 'dart:html'; The only required argument to import is a URI specifying the library. For built-in libraries, the URI has the special dart: scheme. For other libraries, you can use a file system p...

Unlike Java, Dart doesn’t have the keywords public, protected, and private. If an identifier starts with an underscore _, it’s private to its library. If you for example have class A in a separate library file (eg, other.dart), such as: library other; class A { int _private = 0; testA()...

If you import two libraries that have conflicting identifiers, then you can specify a prefix for one or both libraries. For example, if library1 and library2 both have an Element class, then you might have code like this: import 'package:lib1/lib1.dart'; import 'package:lib2/lib2.dart' as lib2; /...

If you want to use only part of a library, you can selectively import the library. For example: // Import only foo and bar. import 'package:lib1/lib1.dart' show foo, bar; // Import all names EXCEPT foo. import 'package:lib2/lib2.dart' hide foo;

Deferred loading (also called lazy loading) allows an application to load a library on demand, if and when it’s needed. To lazily load a library, you must first import it using deferred as. import 'package:deferred/hello.dart' deferred as hello; When you need the library, invoke loadLibrary() us...

Use pub build when you’re ready to deploy your web app. When you run pub build, it generates the assets for the current package and all of its dependencies, putting them into new directory named build. To use pub build, just run it in your package’s root directory. For example: $ cd ~/dart/hellowo...

This command starts up a development server, or dev server, for your Dart web app. The dev server is an HTTP server on localhost that serves up your web app’s assets. Start the dev server from the directory that contains your web app’s pubspec.yaml file: $ cd ~/dart/helloworld $ pub serve Servin...

C99 Using the system header file stdbool.h allows you to use bool as a Boolean data type. true evaluates to 1 and false evaluates to 0. #include <stdio.h> #include <stdbool.h> int main(void) { bool x = true; /* equivalent to bool x = 1; */ bool y = false; /* equivalent t...

There are 2 ways of instantiating prefabs: during design time or runtime. Design time instantiation Instantiating prefabs at design time is useful to visually place multiple instances of the same object (e.g. placing trees when designing a level of your game). To visually instantiate a prefab...

It is a good practice to provide expression string arguments as braced strings. The heading "Double Substitution" outlines important reasons behind the same. The expr command evaluates an operator-based expression string to calculate a value. This string is constructed from the arguments ...

JavaScript has native conversion from Number to it's String representation for any base from 2 to 36. The most common representation after decimal (base 10) is hexadecimal (base 16), but the contents of this section work for all bases in the range. In order to convert a Number from decimal (base...