public long getDataTypeId() {
		validate(lock);
		// record always present when use of datatype ID is supported (i.e., external location)
		Field value = record.getFieldValue(SymbolDatabaseAdapter.SYMBOL_DATATYPE_COL);
		if (value.isNull()) {
			return -1;
		}
		return value.getLongValue();
	}
@see ghidra.program.model.symbol.Symbol#setPrimary()
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/symbol/SymbolDB.java