Hi, I very need help, maybe someone have LimeSurvey database logical model or some UML diagramas of system?

Hi,
if you have LimeSurvey installed you may do it by yourself.
With tools that re-engineer the database like fabforce dbdesigner, or MySQL workbench, or others.

Joffm

Thanks for the answer, Yes I know that, I export MySQL dump file from limesurvey and import in MySQL workbench, but I have only tables I don't see relationships connections.

Are you sure there are some?

Foreign Keys and MyISAM tables?

Joffm

When I import database in MySQL workbench I see only tables like in image without tables realationships.

And I asked: Are you sure there are some?

Foreign keys and MyISAM tables?

Two posts from Stackoverflow:

I can't see any reference elsewhere in the current documentation to indicate that FK constraints are still intended for MyISAM in the future, nor can I see any specific documentation/discussion/record for this change. So yes, I would guess it is no longer planned

I do remember the times when mysql had only myisam and innodedb was in development. MyIsam has no foreign keys because it is old system that does not support relations in database. It will never use foreign keys! To Use it you have innodb. If you don't need all stuff, like relations in DB, use MyISAM to get better performance.