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8 Ways to Optimize AWS Glue Jobs in a Nutshell

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  Improving the performance of AWS Glue jobs involves several strategies that target different aspects of the ETL (Extract, Transform, Load) process. Here are some key practices. 1. Optimize Job Scripts Partitioning : Ensure your data is properly partitioned. Partitioning divides your data into manageable chunks, allowing parallel processing and reducing the amount of data scanned. Filtering : Apply pushdown predicates to filter data early in the ETL process, reducing the amount of data processed downstream. Compression : Use compressed file formats (e.g., Parquet, ORC) for your data sources and sinks. These formats not only reduce storage costs but also improve I/O performance. Optimize Transformations : Minimize the number of transformations and actions in your script. Combine transformations where possible and use DataFrame APIs which are optimized for performance. 2. Use Appropriate Data Formats Parquet and ORC : These columnar formats are efficient for storage and querying, signif
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How to Use Python Try and Except Logic Correctly

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In Python, you can avoid exceptions using Try and Except logic. The Error-free programs save a lot of time. Also, you can keep away defects in production.
 

Python tips
How to Use Python Try and Except Logic Correctly


In Python, you can handle un-known errors by using TRY and EXCEPT logic. If the programmer does not take care of this, the default is for Python to print an error message and stops execution. 



So the responsibility of a programmer is upfront he/she has to find errors and handle them correctly. It is possible if you use the TRY and EXCEPT.


Python Syntax for Try and Except.


try:
      c = a/b
except:
      c = 1000000

Try ends with ':' it says that Try block start here. In this block, you can write actual logic. The Except: is another block. That means in this block programmer can specify some value. And that value populates when any error happens.

Try and Except Examples.

Example: 1.

Below is the example to give the expected error in except.

try:
      c = a/b
except ZeroDivisionError:
      c = 1000000


The above example is you can give a name to an error in Except.  When this error happens, it assigns 1000000.


Example: 2.

Below is an example to give anticipated errors.

try:
      c = a/b
except (ValueError, ZeroDivisionError):
      c = 1000000


Also, there can be many except statements associated with a single Try.

Example: 3.

Below is an example to use multiple excepts.

try:
      c = a/b
except ValueError:
    c = 0
except ZeroDivisionError:
      c = 1000000

And, as was mentioned, a variable can hold the value of the error to be caught:

Example: 4.

The below example is to assign a value to the variable when an error happens. 

k = ZeroDivisionError
try:
      c = a/b
except k:
      c = 1000000


If we left out the exception name, it assigns value C for other errors.

try:
      c = a/b
except:
      c = 0


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