public long getMaxKey() {
		return tableRecord.getMaxKey();
	}
Get the maximum record key which has ever been assigned within this table.
This method is only valid for those tables which employ a long key and may
not reflect records which have been removed (i.e., returned key may not 
correspond to an existing record).
@return maximum record key.
Ghidra/Framework/DB/src/main/java/db/Table.java