Data Consistency Between 2 Mysql Databases Running Different Versions

I need to migrate an old web application using old php and mysql versions. I am intending to start by migrating the code that interacts with the database to a new server with the latest versions and allow the old server to use an API in the new server. Ideally I would like to have the data consistent between the database in the new server and the one in the old server. It seems that replication only works only when the master is only one version behind the slave. In this case the difference is a way more than one version. I also want changes to the database on the new server to reflect on the database on the old server. Are there any tools/techniques to help with this situation other than ensuring the data consistency programmatically with cron jobs …. If something is not clear please let me know and all suggestions are welcome.

Azure elastic pool: Can I create as many databases as I want?

I am sitting here trying to figure out what the elastic pool in Auzre gives me. I have a customer that wants a guess on pricing if the move to Azure. They have 3 databases, on a server. The server has 96 GBs of RAM and a 3.4 Ghz processor. That is all i know. The three databases is sharing these specs, and each database has it own area of expertise:

  1. one database handles all the CMS data
  2. the second database handles all the commerce data
  3. the third database is a database that stores user info, etc – all data that doesnt fit the two others

I think the usage pattern is pretty diverse, so sometimes the commerce is using a lot of RAM and CPU, other times it is the CMS etc.

I dont think they fit well into a single database, because they are going to need three big databases then, and almost all of them is going to be under utilized all the time. So I thought about elastic pools.

The describtion of ealstic pools fits the above very well: all databases shares eDTUs. Perfect! But one thing the docs doesnt describe is: do i pay for the elastic pool AND pr database? Or do I just create databases on the fly, and all of them shares, that is: the databases is free, but you pay for the eDTU.

I have read this https://docs.microsoft.com/en-us/azure/sql-database/sql-database-elastic-pool – but they don’t describe it.

Hope someone can give me some more info.

Data Model or Data Structure for Stored Procedures in Databases

I know that Relational Algebra is the goto data model for storing information related to SQL queries.

I am however yet to find a standard data model that can encapsulate constructs of stored procedures such as cursors, loops, in/out variables, statements etc.

I might be wrong, but usually people talk about an AST, but is there something more specific? I tried looking into MySQL code to get some idea but wasn’t too successful.

Auto-Shrinking All Databases Files To Their Minimum Size In Sql Server

I restore my all databases in production to my development environment monthly. Development server has 4 TB disk space and there are 4 different instances over it which containt databases on the production server. In Development, i can truncate and shrink some big-sized tables to expand free disk space. The purpose of doing this process is the complaint of software developers about the development server slowness. I talked to system administrator team and they informed me that the slowness was because of the insufficient disk space area. So, i make this work. My question is about how i can shrink all database files to their minimum size after truncating related tables. So, should i make it with powershell, and how?

Why is VACUUM FULL locking ALL databases on the cluster?

From everything I have read about VACUUM FULL, I would expect it to lock the database I’m running it on, but it renders every database in the cluster inaccessible. Is there perhaps something we might have wrong in our configuration? I do have autovacuum on, but we have a few unwieldy databases I’d like to clean up thoroughly. This is PostgreSQL v10. Thanks for any insights.

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.

Thanks!