Subject Possibility to increase the maximum number of tables
Author hi.egor
From the first look at the system tables and their relations the reason of this limit is related to the datatype SHORT of column RDB$RELATION_ID of table RDB$RELATIONS and other related columns from tables ("RDB$DATABASE", "RDB$FORMATS", "RDB$PAGES"). Also I noticed that relations between different internal DB objects (such as columns, tables, indexes) are based on the "Table Name" (RDB$RELATION_NAME), but not "Table ID" (RDB$RELATION_ID). Looks like the primary used of RELATION_ID is to identify the PAGE in the data file.
Consider these thoughts it seems to be not such a big and complex task to change SHORT datatype to for example LONG for RELATION_ID column (and related to it source code) to increase the maximum number of tables.