1. Apache Pig Pros and Cons
As we all know, we use Apache Pig to analyze large sets of data, as well as to represent them as data flows. However, Pig attains many more advantages in it. In the same place, there are some disadvantages also. So, in this article of “Pig Advantages and Disadvantages”, we will discuss all advantages as well as disadvantages of Apache Pig in detail.
2. Introduction to Apache Pig
Apache Pig is nothing but a data flow language. It is built on top of Hadoop. Basically, without having to write vanilla MapReduce jobs, it makes easier to process, clean and analyze “Big Data” in Hadoop.
In addition, it has a lot of relational database features. Moreover, commands like good old joins, distinct, union and many more are already in the language. To be specific, Pig solves differently than the relational database, so it is applicable to “big data” where it can crunch large files with ease and it does not need a structured data. Also, we can use Pig for ETL(Extraction Transformation Load) tasks naturally as it can handle unstructured data. Now, let’s jump to Pig advantages and disadvantages.
3. Advantages and Disadvantages of Apache Pig
Let’s discuss both Apache Pig Pros and Cons individually:
a. Advantages of Apache Pig
i. Less Development time
It consumes less time while development. Hence, we can say, it is one of the major advantages. Especially considering vanilla MapReduce jobs’ complexity, time-spent, and maintenance of the programs.
ii. Easy to learn
Well, the Learning curve of Apache Pig is not steep. That implies anyone who does not know how to write vanilla MapReduce or SQL for that matter could pick up and can write MapReduce jobs.
iii. Procedural language
Apache Pig is a Procedural language, not declarative, unlike SQL. Hence, we can easily follow the commands. Also, offers better expressiveness in the transformation of data in every step. Moreover, while we compare it to vanilla MapReduce, it is much more like the English language. In addition, it is very concise and unlike Java but more like Python.
It is a data flow language. That means here everything is about data even though we sacrifice control structures like for loop or if structures. By “this data and because of data”, data transformation is a first class citizen. Also, we cannot create for loops without data. We need to always transform and manipulate data.
v. Easy to control Execution
We can control the execution of every step because it is procedural in nature. Also, a benefit that it is, straightforward. That implies we can write our own UDF(User Defined Function) and inject in one specific part in the pipeline.
It is possible to write our own UDFs.
vii. Lazy evaluation
As per its name, it does not get evaluated unless you do not produce an output file or does not output any message. It is a benefit of the logical plan. That it could optimize the program beginning to end and optimizer could produce an efficient plan to execute.
viii. Usage of Hadoop Features
Through Pig, we can enjoy everything that Hadoop offers. Such as parallelization, fault-tolerance with many relational database features.
ix. Effective for Unstructured
Pig is quite effective for unstructured and messy large datasets. Basically, Pig is one of the best tools to make the large unstructured data to structured.
x. Base Pipeline
Here, we have UDFs which we want to parallelize and utilize for large amounts of data.That means we can use Pig as a base pipeline where it does the hard work. For that, we just apply our UDF in the step that we want.
b. Limitations of Apache Pig
i. Errors of Pig
Errors that Pig produces due to UDFs(Python) are not helpful at all. At times, while something goes wrong, it just gives the error such as exec error in UDF, even if the problem is related to syntax or the type error, it lets alone a logical one.
ii. Not Mature
Pig is still in the development, even if it has been around for quite some time.
Generally, Google and StackOverflow do not lead good solutions for the problems.
iv. Implicit Data Schema
In Apache Pig, Data Schema is not enforced explicitly but implicitly. It is also a huge disadvantage. As it does not enforce an explicit schema, sometimes one data structure goes byte array, which is a “raw” data type. It is up to the time we coerce the fields even the strings, they turn byte array without notice. It leads to propagation for other steps of the data processing.
v. Minor one
Here is an absence of good IDE or plugin for Vim. That offers more functionality than syntax completion to write the pig scripts.
vi. Delay in Execution
Unless either we dump or store an intermediate or final result the commands are not executed. This increases the iteration between debug and resolve the issue.
This was all on Pig Advantages and Disadvantages.
As a result, we have seen all the Pig advantages and disadvantages. However, if any doubt occurs, feel free to ask in the comment section.