void deleteExternalEntries(Address start, Address end) throws IOException {
		AddressRecordDeleter.deleteRecords(symbolTable, SYMBOL_ADDR_COL, addrMap, start, end, null);
	}
SymbolDatabaseAdapter for version 3

This version added additional sparse columns to store optional data specific to certain
symbol types.  The adhoc string data column was eliminated.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/symbol/SymbolDatabaseAdapterV4.java