Oracle – loop through list of databases to check status

I have a table with database names and connection strings. Do you know any method to loop through the list of database names (and/or the connection details) and test database connectivity (just need to know if database is up)? The only problem is that I do not have DBLinks pointing to these databases, but we do use OID if that could be of any help/use.


Many databases combined with MariaDB Spider engine tables [on hold]

We are in the process of refactoring the architecture of our main ETL process in our company.

Basically, the process:

  1. Extracts data from WebServices, MySQL Databases, etc.
  2. The data gets standarized.
  3. The data gets saved in our database.

The data sources are other businesses integrations. We develop a new integration for every client. A integration is given by an extractor application, specifically adaptaed to the sources endpoints (mainly some WebServices). The data extracted is then sent to AWS SQS queues for standarization. The standarizer app runs every hour consuming the messages. Once they’re standarized, messages are sent to another queue (the saver queue). Every hour, the saver app runs and process the messages, saving the content in our database.

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Since we’re growing in the number of business integrations, our database is getting some stress during the ETL process and we fear the we’ll end up in a bottleneck. Mainly because of the huge amount of write IOPS that the saver introduces in the main database.

I’m currently in charge of the refactor and I came up with the following architecture design. Given the modular design of the saver and standarizer, they could be “packed” in a app stack alogn with the extractor and a dedicated database for each business. Like so:

enter image description here

The ? labeled box is because the consumer API executes some query over the database that required that all the data is stored on a single database (some reducing, grouping, etc), so, a service of some kind should be present there to let the Consumer API app execute those queries as if a single database is still present.

Doing some research I found MariaDB’s Spider storage engine as an option. Basically, what I was thinking is to mount a EC2 instance with MariaDB installed, and define tables that are partitioned across the businesses databases. That way, the Consumer API will think that only a single database exists, and would let MariaDB take care of the SQL request distributed across each database.

My question is:

Is this a valid use case for the Spider engine?+

To take in mind:

  1. We are not in a position of implementing a ESB (small team, low cost)
  2. We must avoid refactoring the SQL queries of the Consumer API.

Thanks in advance.

Associative Qualities in Relational and Dimensional Databases

Aside from how these structures differ in application (what they do), is it accurate to state that Dimensional Models represent composite entities (collection of primary keys) embodied by a fact table interconnected with its dimensions (foreign keys) and attributes – a “star” schema of relations?

Hoping for general conversation to define the interrelated concepts.

Is back-end only working on DataBases? [on hold]

I have a problem to exactly understand what is the back-end developer meaning? What do exactly back-end developers do? Is their job only working on DataBases?

When I see front-end developers, they design and make the UI, then they even write the codes of buttons, Menus, drawers, progressbars, tabs, etc to make them working.

So the question comes to my mind, what really back-end developers do and is their job only working on Databases or they do have more jobs that I didn’t mention in my above example?

Or maybe better to ask: What part of a project/software is called back-end?

2013 to 2016: Upgrade all DB’s? Or just Content Databases?

I am in the process of completing a Farm Upgrade from 2013 to 2016. I have the new 2016 Farm built and configured, and am ready to transfer the databases.

I know that I don’t need to move the following: (Already created on new 2016 farm). Sharepoint_Config, Sharepoint_AdminContent.

I know that I do need to move the following: WSS_Content_xxxxxxxxxxxxxx, WSS_Content_MySites, WSS_Logging, Search_Service_Application, Secure_Store.

However: Should I also move the following?

SbGatewayDatabase, SbManagementDB, SBMessageContainer01, SocialDB, ProfileDB, WFInstanceManegment, WFResourceManagement.

Multiple db.crypt12 databases in the whatsApp Databases folder

I’m trying to reduce space eaten by the whats-app application on my phone & PC
I see Multiple db.crypt12 databases in the whats-app Databases folder
This is probably due to me copying the app folders to my PC over the years for backup..
Is it possible to remove the least used once?
is it correct that whats-app is using only one of the databases?

whats-app databases

How do I remove apache2 without losing lampp and databases?

I installed lampp (7.3) on ubuntu (18.4). Then I started lampp (sudo /opt/lampp/lampp start) and created my projects and databases with mysql. I could see my projects and databases with visiting (localhost) and (localhost/phpmyadmin). After that, I installed apache2 (2.4.29) to just test it. Now, when I want to start lampp with this command “sudo /opt/lampp/lampp start”, it starts apache2 instead of lampp and I can’t access my projects and tables with (localhost or localhost/phpmyadmin).

  1. Can I access my “lampp tables” in apache2?
  2. If I want to keep my lampp, is it necessary to remove apache2?
  3. Which command can start lampp instead of apache2?
  4. How can I remove apache2 without removing lampp?