That is very dangerous to do, the same bytes might be reused differently in a newer ODS. Either use a normal Firebird table to store version info, or do it outside of the database. Do not hack things in the internal structure.

The page header is not a good place to stick information. It does change to support new features.  However, the database header page has a place that you might be able to use.  The format of the header page is defined in ods.h.   The first part is fixed.  The second part is a string of "clumplets" which are groups of attribute-length-data triplets.  By design, Firebird skips over clumplets it doesn't understand.  You could write a program that adds a new clumplet of a type undefined by Firebird to hold your version information.  It wouldn't survive a gbak backup/restore cycle.

The discussion was about finding portable mechanism to identify the application version of a database.  Are you aware that databases are not portable across machines with different endian characteristics?

Good luck,

Ann 

 

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