What is Pig architecture?
Apache Pig architecture consists of a Pig Latin interpreter that uses Pig Latin scripts to process and analyze massive datasets. Programmers use Pig Latin language to analyze large datasets in the Hadoop environment.
How do you write a Pig script?
Executing Pig Script in Batch mode
- Write all the required Pig Latin statements in a single file. We can write all the Pig Latin statements and commands in a single file and save it as . pig file.
- Execute the Apache Pig script. You can execute the Pig script from the shell (Linux) as shown below. Local mode.
How do you run a Pig query?
To run the Pig scripts in local mode, do the following:
- Move to the pigtmp directory.
- Execute the following command (using either script1-local. pig or script2-local. pig).
- Review the result files, located in the script1-local-results. txt directory.
How do you use the Apache Pig?
First, to process the data which is stored in the HDFS, the programmers will write the scripts using the Pig Latin Language. Internally Pig Engine(a component of Apache Pig) converted all these scripts into a specific map and reduce task.
What is the difference in Pig and SQL?
Apache Pig Vs SQL Pig Latin is a procedural language. SQL is a declarative language. In Apache Pig, schema is optional. We can store data without designing a schema (values are stored as $01, $02 etc.)
What is Pig programming language?
Pig is a high level scripting language that is used with Apache Hadoop. Pig enables data workers to write complex data transformations without knowing Java. Pig’s simple SQL-like scripting language is called Pig Latin, and appeals to developers already familiar with scripting languages and SQL.
How do Pig scripts load data?
movies = load ‘/home/hadoop/Desktop/script/sample. csv’ using PigStorage(‘,’) as (id,name,year,rating,duration);
Why are pigs used?
Pig is used to perform all kinds of data manipulation operations in Hadoop. It provides the Pig-Latin language to write the code that contains many inbuilt functions like join, filter, etc. The two parts of the Apache Pig are Pig-Latin and Pig-Engine.
Does Pig require Java?
It is a low-level data processing tool. It is a high-level data flow tool. Here, it is required to develop complex programs using Java or Python.
How does pigunit test work?
If the pig.notification.listener.arg parameter is set, the value will be passed to a constructor of the implementing class that takes a single String. PigUnit is a simple xUnit framework that enables you to easily test your Pig scripts. With PigUnit you can perform unit testing, regression testing, and rapid prototyping.
How to access Hadoop Statistics in pig?
The new Pig statistics and the existing Hadoop statistics can also be accessed via the Hadoop job history file (and job xml file). Several new public classes make it easier for external tools such as Oozie to integrate with Pig statistics.
How does a sample pipeline algorithm work?
The algorithm works by retrieving a small sample of the input data and then propagating this data through the pipeline. However, some operators, such as JOIN and FILTER, can eliminate tuples from the data – and this could result in no data following through the pipeline.
What is the use of pigunit in Eclipse?
PigUnit is a simple xUnit framework that enables you to easily test your Pig scripts. With PigUnit you can perform unit testing, regression testing, and rapid prototyping. No cluster set up is required if you run Pig in local mode.