如果 table2 用到 table1 外鍵非 table2 主鍵欄位,可以先 update 為空,然後再 drop table1,否則drop table2 的外鍵關係 再 drop table1。
DELETE FROM tblRoadList where RoadID='0283' cascade;
alter table 2 drop constraint FK_TBLSECTL_REFERENCE_TBLROADL; alter table 2 add constraint FK_TBLSECTL_REFERENCE_TBLROADL foreign key(...) references 1(...) on delete cascade; 层叠删除。
alter table 2 add constraint FK_TBLSECTL_REFERENCE_TBLROADL foreign key(...) references
1(...) on delete cascade;
层叠删除。