DBMONEY: the currency symbol for the money column values in the external data file are in the format specified by the DBMONEY.
DBMONEY：外部数据文件中的货币列值的货币符号采用由DBMONEY指定的格式。
2
They use the percent (%) symbol instead of the ampersand, and can be either named entities or external entities.
它们使用百分号（%）而不是与字符，可以是命名实体或外部实体。
3
The function S1 is defined outside of the current file, and because the compiler doesn't actually know where the external function is, we leave this part of the symbol table blank for now.