EHN: Add new base schema (db_5_0.sql) for installation

Summary

#32 (closed)

The Schema had once (until 2016 A.D.) a table named "groups" which is a keyword since MySQL 8. It is not part of the currenty schema (v5.0.0) anymore, but it has been created (as part of schema (v.2.0.1) and then been removed again in a patch from 2016-04. This is why the installation fails on MySQL 8 (and will likely fail on future MariaDB versions).

This MR adds a new schema installer (on the basis of our schema v5.0.0, without the groups table) and removes tables and functions which turned out to be unused during the review of the new db_5_0.sql file.

Focus

Obviously, there is not much really changing here. The new db_5_0.sql which replaces db_2_0.sql is just a dump of fresh installation with the old installer. A few tweaks had to be made (order of table creation and some tweaks to set some INT UNSINGED AUTOINCREMENT values to zero).

Just note that

• the function retrieveGroup was referencing the (deleted) groups table.
• the table logging is an unused remnant of a never-finished logging persistence functionality (We use a proper logging framework now, which has its own persistence functionality).

Test Environment

No manual testing required. Just make sure that the complete pipeline succeeds (mysqlbackend, deploy, pyinttests)

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  • Intent of new code
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