AWS Athena @ Freshers.in

Amazon Athena quick reference and cheat sheet

1. Amazon Athena is an interactive query service to analyze data in Amazon S3 using standard SQL. 2. Athena is…

python @ Freshers.in

Python throwing as NameError: name ‘__file__’ is not defined – Solution

On Executing  os.path.dirname(os.path.realpath(__file__)) in python interactive shell, you will get the error NameError: name ‘__file__’ is not defined. This is…

amazon_api_gateway @ Freshers.in

Amazon API Gateway quick reference and cheat sheet

1. Amazon API Gateway is an AWS service for creating, publishing, maintaining, monitoring, and securing REST, HTTP, and WebSocket APIs…

Hive @ Freshers.in

How to drop multiple partition in Hive by giving condition.

Hive Partitions is a good and easy way to organizes Hive tables into partitions by dividing tables into different parts…

Hive @ Freshers.in

How to delete a partition data as well from Hive external table on DROP command?

As you know external tables are tables where  Hive does not manage the data of the External table. So when…

Hive @ Freshers.in

How to convert a hive managed table to external table without recreating it ?

In Hive, Managed tables / Internal table are Hive owned tables and the tables data are managed and controlled by…

AWS Redshift @ Freshers.in

How to do Force serialization in AWS Redshift table by locking all tables?

You can force serialization by locking all tables in each session. The LOCK command blocks operations that would result in…

AWS Redshift @ Freshers.in

Serializable isolation violation on table in Redshift : ERROR: 1023 : Resolved solution

When you run concurrent Amazon Redshift operations in different sessions, there is a probability of getting “ERROR: 1023 DETAIL: Serializable…

PySpark @ Freshers.in

How to concatenate multiple columns in a Spark dataframe

concat_ws : With concat_ws () function you can  concatenates multiple input string columns together into a single string column, using…