Many Ways to Optimize an OLTP Database Running PostgreSQL

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Updated on 2/1/22
Tuning relational databases and related processes can be somewhat simple or very complex. OLTP databases have many processes governing the usage of resources. Optimizing these and keeping locks granular and efficient in accord with business requirements is key to having high performance and reliability.

Studying the business requirements carefully can allow you to redesign the database and the SQL queries to make things happen more efficiently.

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How Do You Install pip on a RHEL Server in AWS?

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Problem scenario
You want to install pip on a RedHat Enterprise Linux server in AWS.  What do you do?

Solution
Prerequisites
This assumes that Python has been installed. If it has not, run this command:
sudo yum -y install python3


Procedures
You may want to try these two commands first:

sudo find / -name pip
sudo find / -name pip3

If the above did not help you,

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What is the Difference between a Readiness Probe and a Liveness Probe in Kubernetes?

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Question
What is a difference between a readinessprobe and a livenessprobe besides how the corresponding fields are used in defining a Pod using YAML?

Answer
At most a failed liveness probe will result in the restarting of a container. At most a failed readiness probe will result in the removing a pod from the endpoint of a service (page 150 of Kubernetes in Action).

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How Do You Open a Port to Connect to a GCP server?

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Problem scenario
You are used to AWS Security Groups. You created a firewall rule in GCP. You cannot seem to reach the GCP server. What is wrong?

Possible Solution
Does the GCP firewall rule use the same shorthand notation like this?
x.x.x.x/32

Inbound rules in AWS Security Groups use the /32 to allow an IP address to connect to an EC-2 instance or service.

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What Database Does Elastic Search Use?

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Question
What SQL database underlies Elastic Search?

Answer
There is no relational database for Elastic Search.

Elastic Search will have a cluster that is composed of nodes. Nodes are composed of indexes. Indexes are supported by shards. Shards have primary and replica copies. The replica copies vary. The shards are essentially Lucene indexes (according to this site).

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In the Context of Linux, what is a System Call?

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Question
In the context of Linux, what is a system call?

Answer
A system call is a special OS function with a human-readable name (according to page 11 of Sobell’s A Practical Guide to Fedora and RedHat Enterprise Linux). Such a function allows for programs to interact with the kernel (according to page 11 of Sobell’s A Practical Guide to Fedora and RedHat Enterprise Linux).

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How Do You Troubleshoot the boto Message “NoRegionError”?

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Problem scenarios (one or both of the following are happening)
#1 You are getting “botocore.exceptions.NoRegionError: You must specify a region” when you run a Python program (that involves boto and AWS).

#2 You are trying to create a session with a Python/boto program. You are printing out the Session information in your Python program using boto but you see this:

Session(region_name=None)

What should you do?

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