SAP 中执行外部 SQL 查询的方法及问题

目前的问题是，此处理方法，暂时还不确认如何和外部DB 进行配置？

"Set Connection to Quotation DB 联接外部数据库及Server ：？可能需要对应的 dll 和SAP 关联

" 先设定
concatenate 'QTN_' sy-mandt into lv_qtn.
case s_vbeln-low(1).
when '5'.
concatenate lv_qtn '_EIL' into lv_qtn.
when '6'.
concatenate lv_qtn '_CAL' into lv_qtn.
when '3'.
concatenate lv_qtn '_CSL' into lv_qtn.
when '8'.
concatenate lv_qtn '_CM' into lv_qtn.
endcase.

" 联接

if wa_sql_flag = 'X'.
EXEC SQL.
connect to :lv_qtn
ENDEXEC.

EXEC SQL.
SET CONNECTION :lv_qtn
ENDEXEC.
endif.

...

*"Disconnect Quotation DB ：最后需要断开联接
**************************************************
if wa_sql_flag = 'X'.
EXEC SQL.
DISCONNECT :lv_qtn
ENDEXEC.
endif.
**************************************************

中间的执行语名示例：

EXEC SQL PERFORMING loop_fab_output.
SELECT quotation_no, scenario_no, rec_level, major_trim_type,
material_type, consum_per_doz, uom, total
INTO :wa_qtn_fab
FROM qn_major_fabric_dtl
WHERE quotation_no = :lv_qtnno
AND scenario_no = :lv_scrno
AND rec_level = :lv_reclv
ENDEXEC.

FORM loop_fab_output.
clear it_qtn_fab.
it_qtn_fab-vbeln = it_vbak-vbeln.
it_qtn_fab-quotation_no = wa_qtn_fab-quotation_no.
it_qtn_fab-scenario_no = wa_qtn_fab-scenario_no.
it_qtn_fab-rec_level = wa_qtn_fab-rec_level.
it_qtn_fab-mat_type = wa_qtn_fab-mat_type.
it_qtn_fab-material = wa_qtn_fab-material.
it_qtn_fab-width = 'N/A'.
it_qtn_fab-consum = wa_qtn_fab-consum.
it_qtn_fab-uom = wa_qtn_fab-uom.
it_qtn_fab-total = wa_qtn_fab-total.
collect it_qtn_fab.
ENDFORM. " loop_fab_output