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Step-by-Step Guide to Creating an AWS RDS Database Instance

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 Amazon Relational Database Service (AWS RDS) makes it easy to set up, operate, and scale a relational database in the cloud. Instead of managing servers, patching OS, and handling backups manually, AWS RDS takes care of the heavy lifting so you can focus on building applications and data pipelines. In this blog, we’ll walk through how to create an AWS RDS instance , key configuration choices, and best practices you should follow in real-world projects. What is AWS RDS? AWS RDS is a managed database service that supports popular relational engines such as: Amazon Aurora (MySQL / PostgreSQL compatible) MySQL PostgreSQL MariaDB Oracle SQL Server With RDS, AWS manages: Database provisioning Automated backups Software patching High availability (Multi-AZ) Monitoring and scaling Prerequisites Before creating an RDS instance, make sure you have: An active AWS account Proper IAM permissions (RDS, EC2, VPC) A basic understanding of: ...

The best helpful HDFS File System Commands (2 of 4)

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#Top-Selected-HDFS-file-system-commands
CopyFrom Local
Works similarly to the put command, except that the source is restricted to a local file reference.
hdfs dfs -copyFromLocal URI
hdfs dfs -copyFromLocal input/docs/data2.txt hdfs://localhost/user/rosemary/data2.txt

HDFS Commands Part-1of 4

copyToLocal
Works similarly to the get command, except that the destination is restricted to a local file reference.
hdfs dfs -copyToLocal [-ignorecrc] [-crc] URI
hdfs dfs -copyToLocal data2.txt data2.copy.txt

count
Counts the number of directories, files, and bytes under the paths that match the specified file pattern.
hdfs dfs -count [-q]
hdfs dfs -count hdfs://nn1.example.com/file1 hdfs://nn2.example.com/file2

cp
Copies one or more files from a specified source to a specified destination. If you specify multiple sources, the specified destination must be a directory.
hdfs dfs -cp URI [URI …]
hdfs dfs -cp /user/hadoop/file1 /user/hadoop/file2 /user/hadoop/dir

du
Displays the size of the specified file, or the sizes of files and directories that are contained in the specified directory. If you specify the -s option, displays an aggregate summary of file sizes rather than individual file sizes. If you specify the -h option, formats the file sizes in a "human-readable" way.

hdfs dfs -du [-s] [-h] URI [URI …]
hdfs dfs -du /user/hadoop/dir1 /user/hadoo

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