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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

SQL Tester Ideas DATE, Numeric, CHAR, NULL

I have shared top SQL Date functions along with Numeric, CHAR and NULL functions.


sql examples on built-in functions


List of Built-in Functions

  1. DATE-TIME functions
  2. Numeric functions
  3. Char functions
  4. Null-related functions

1. DATE/TIME functions

SELECT p_code,
launch_dt,
CURRENT_DATE
FROM product;

CURRENT_DATE returns the CURRENT date.

SELECT p_code,
To_char(launch_dt, 'DD MONTH YYYY') reformatted_dt
FROM product;
TO_CHAR FUNCTION returns date IN char format.

2. Numeric functions

SELECT p_code,
price,
(price - 20),
Abs(price - 20.00)
FROM product;


ABS - FUNCTION returns the absolute value


SELECT p_code,
price,
Round (price, 1)
FROM product;


ROUND FUNCTION - round TO 1 digit.


SELECT p_code,
price,
Sign(price - 15)
FROM product;


SIGN FUNCTION - it returns the sign

SELECT p_code,
price,
Trunc(price, 1)
FROM product;


TRUNC FUNCTION - truncates TO a certain number OF decimal places.


3. CHAR functions

SELECT p_code,
Concat(Concat(p_name, ' -- ') , price)
FROM product;CONCAT FUNCTION - concats two strings.




SELECT p_name,
Lower(p_name),
Upper(p_name)
FROM product;


UPPER FUNCTION : returns upper CASE.
Lower FUNCTION returns lower CASE.




SELECT p_name,
Length(p_name)
FROM product;LENGTH FUNCTION
returns length OF the string.


SELECT Substr(phone, 3)

FROM customer;


SUBSTR FUNCTION : returns a substring FROM the main string.


4. Null related functions

SELECT p_name,
price,
min_price,
COALESCE((price * 0.9), min_price, 5.0) sale_price
FROM product;


COALESCE FUNCTION: returns the first non-NULL value FROM the expression.



Summary
  • Given a list of top built-in functions
  • Example SQL queries on built-in function given for you to read quickly
  • These examples are almost common in any RDBMS

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