After installing JMS MultiSite in a fresh Joomla 3.2.3 config, in your maintenance module I see '14 database changes have errors' directly in the master site. After making slave sites, they have the same problem. They are not fixable and it is hard to find the differences in your suggested SQL commands.

Is it a Joomla 3.2.3 problem? Is it a problem?

TIA.
Best wishes,
Joris

The difference between the Joomla / database fix and the JMS Maintenance / Check DB & Fix DB is that in JMS it parses more SQL statement and does not ignore some MySQL statement like in joomla. That means that you have more reporting with JMS in case where Joomla does not apply all the update.

In the JMS 1.3.30 that will be released soon, we have fixed several things and improve the database structure analysis.
We also improved the "legacy mode" that allow several joomla version working with the same DB.
We expect to explain that later after the joomla day in Paris where we will show that.

Ok. But can I ignore it for now? And go on with building slave sites with same reports? Or indicates this a real problem?

We understand that only proceed with the schema update could be interesting.
For the moment, the "maintenance" is able to use the full "install" sql file to make the comparaison and therefore deduct the equivalent of the update / schema.
It is also possible to compare the structure with the master one.

We noticed that it would be good to add in a future version of JMS the possibility to only process the schema update.

Sorry, but it is hard for me to follow you.

Problem 1 is I do not exactly understand what your maintance module is checking and eventually repairing.

Problem 2 is I cannot estimate the severity of the errors. What does it mean in practice: '14 database changes have errors'?

Problem 3 is I do not understand that there are so many 'errors' in just a fresh install of Joomla and your component, before making any slave site. Have I done something wrong? Is it only your checking algorithm?

So, can I ignore this problem, or do I have to take action? And in that case: wich action?

Everything seems to work fine, but I do not wish to be in trouble after building say 10 slave sites.

The "maintenance menu" is doing something different to the database fix present in the extension manager.
The joomla one only work on the extensions that describe the schema and update.

The JMS "maintenance menu" is able to discover the SQL files that are used when you install an extension and after to compare the "install" SQL with the current DB structure to verify that everything is correct.
This is like that that JMS maintenance is able to detect missing update in Joomla database fix because the Joomla one does not compare with a full install but only some statement with other that may be skipped.

In the JMS "maintenance menu", when something is not understood and skipped, you also have the opportunity to apply it.
In addition, when you detect a problem somewhere, you are also able to execute any free SQL statement to apply on a website.

In addition to this "basic" functionlities, the maintenance menu is also able to create a "legacy DB" that can be used by different joomla version.
Because the DB structure are different between the different Joomla version, the legacy mode is able to compare the structure and just add fields (and not remove drop fields).

The objective of the "maintenance menu" is to be able supervise the consistency of your all websites and provide you a tool to potentially fix it on a specific site or apply a specific DB modification in case where you would find an inconsistency somewhere.

The JMS 1.3.30 is now released and you can now see the detection of schema version.
See the FAQ for the procedure to get the latest version
www.jms2win.com/en/faq/faq-joomla-multi-sites#cat-122