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, and I am also a naturalized Swedish citizen. I am a former Oracle ACE and, to keep up with academic research, I…
Year: 2023
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, and I am also a naturalized Swedish citizen. I am a former Oracle ACE and, to keep up with academic research, I am a Computer Scientist with an MSc…
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:…
EXAM PREPARATION – AWS Certified Database – Specialty (DBS-C01)
The AWS Certified Database – Specialty (DBS-C01) y exam has been on my bucket list for a few months. I tried it for the first time on Aug 09, 2022, and I failed. Although I considered that I was not that bad at all, I scored 681, where the minimum passing score is 750: The approach that I took for my first attempt was to buy some courses about the certification at Udemy, which I will no longer share the courses here not to do free merchandising 🙂 , and…
Enabling Active Data Guard in Physical Standby Database
Active Data Guard is the option when the standby database is configured to be in its status open with read-only mode. As explained below in the white paper “Oracle (Active) Data Guard 19c Real-Time Data Protection and Availability,” there are some benefits, dated March 2019: With this in mind, the current post is about enabling your Physical Standby database as an Active Data Guard. Taking as a primary step that you already have a configured Physical Standby database, this post follows the procedures below: All these steps mentioned above, except…
Index WRH$_SYSMETRIC_HISTORY_INDEX Status Unusable After Database Upgrade From 12c To 19c
Upgrading Oracle database 12.2 to 19.10 came with some surprises, and one of them was the invalid status of the index WRH$_SYSMETRIC_HISTORY_INDEX owned by the user SYS. Rebuilding the index helped only temporarily, so I decided to recreate the index by following the procedure below: — Confirmation of the invalid index: — Action plan: For more information, please check the following MOS notes below: Index WRH$_SYSMETRIC_HISTORY_INDEX Status Unusable (Doc ID 2426391.1)WRH$_SYSMETRIC_HISTORY_INDEX Index Does Not Get Partitioned After Database Upgrade From 12c To 19c (Doc ID 2777641.1)Index WRH$_SYSMETRIC_HISTORY_INDEX Status Unusable (Doc…
Enabling SPOOL output using RMAN
I had a performance problem in one of the routine backups, so I opened a Service Request (SR) at MOS (My Oracle Support). After a few hours from the moment I opened the SR, I got a request to upload the output of a few commands. Therefore, I used a SPOOL output to create it. For those unfamiliar with how to create a SPOOL output in the RMAN utility, follow below how you can accomplish this task: brunorsHi! I am Bruno, a Brazilian born and bred, and I am also…
Bug ORA-38881 during “drop tablespace” even though there is NO Guaranteed Restore Point (GRP) – Fixed in version 19.17
I just upgraded one Oracle Database system from 12.2 to 19.10. I was happy with the result until one database procedure started to fail with the message “ORA-38881: Kan inte radera tabellutrymmet TECH_29102_9292 i den primära databasen pga. garanterade återställningspunkter.” . For those unfamiliar with the Swedish language, this is the same error message as “Oracle Error ORA-38881: Cannot drop tablespace string on primary database due to guaranteed restore points.”. I started doing some investigation until I found that there is a BUG:14163359 fixed on version 19.17 of the Oracle databases. And…