I was managing an environment where we needed to investigate the redo log switch frequency in our environment due to some graph spikes visualized using Grafana dashboards. A simple SELECT command using the view V$LOG_HISTORY is required to accomplish this goal. Therefore, below is presented this SQL SELECT command and the output: I hope this post helps you! brunorsHi! I am Bruno, a Brazilian born and bred. Former Oracle ACE, Computer Scientist, MSc in Data Science, over ten years of experience in companies such as IBM, Epico Tech, and Playtech…
Month: April 2023
Archive log not deleting within retention policy
I was managing an ORACLE RAC database configured with Oracle Data Guard when I discovered the archive log was not being deleted after the retention policy of 2 days in our backup configuration. Therefore, I started the investigation by collecting some information from the alert log. And the first initiative I took was to verify if the database had been deleting old archives when there was a space pressure in the recovery area as below: It is a cheerful and ordinary Oracle database approach to automatically deleting unneeded files. The…
Managing the availability of a portable collection of schemas, schema objects, and non-schema objects in an Oracle multitenant database
This post serves as a reference to close and open PDB databases. I have been mentoring some colleagues on the way to a data and database management career. As we have been managing Oracle multitenant environments quite often, I decided to create an example where they can easily visualize and have a reference on it. I made another blog post where one can imagine the existence of PDBs (https://www.techdatabasket.com/2018/11/08/how-to-check-if-my-database-is-a-cdb-database-or-not/). Thus, follow below is the representation of the closing and opening of a database instance named TECHDB in an Oracle RAC…
TIDB – CREATE DATABASE command
After creating a local cluster for the TiDB database and visualizing the existing database via the show database command, I decided to create a database. And like many open-source databases, TiDB simplifies this activity by using a simple command as “create database.” Therefore, this post shows how quickly create a new database followed by the latest display of the existing databases: brunorsHi! I am Bruno, a Brazilian born and bred. Former Oracle ACE, Computer Scientist, MSc in Data Science, over ten years of experience in companies such as IBM, Epico Tech, and…
TiDB – SHOW DATABASES Command
After creating a local TiDB platform, I would like to get started with some typical commands, such as listing the databases. Therefore, this post presents an example of how to display the databases to the connected user who has access: Note*: “The information_schema database always appears first in the list of databases.” Source: https://docs.pingcap.com/tidb/dev/sql-statement-show-databases brunorsHi! I am Bruno, a Brazilian born and bred. Former Oracle ACE, Computer Scientist, MSc in Data Science, over ten years of experience in companies such as IBM, Epico Tech, and Playtech based in three different countries (Brazil,…
Quickly deploy of a TiDB database for mac OS (macOS) – local test cluster
This post is about deploying a TiDB database in a non-productive environment. I intend to try the features of Hybrid Transactional and Analytical Processing (HTAP) workloads of this open-source distributed SQL database. It was mind-blowing when I heard about the possibility of a database maintaining the scalability of a NoSQL database while keeping the ACID transactions of a relational database. Therefore, I will follow the procedure “Deploy a local test cluster” found on the official documentation for MacOS as below: 1- Download and install TiUP: Command: Execution: 2- Declare the…
EXAM PREPARATION – AWS Certified Machine Learning – Specialty
I have been studying not only for this certification of Machine Learning but for other in Data Engineering since I started my master’s studies in Data Science a few years ago. And the reason behind that is that I was already working with the AWS console and was overwhelmed with the changing data management I saw while a database administrator. I still remember everyone talking about this Machine Learning thing, and I had no clue back then what it was. I was seen many database administrators mistakenly changing their role…
Transforming .CSV format file in Apache Parquet format via Amazon Glue
I had the task of storing a .CSV format file in an Amazon S3 storage, but the pre-requisite was converting this .CSV format file to Apache Parquet format. Thinking from this perspective, I assume that one of the reasons for this conversion is to reduce costs, and for that, the tool Amazon Glue is the perfect tool to accomplish this task. I thought to describe and show my implementation here, but I realized that there are many how-tos that I followed, and their link is shared below as a source:…