我在 Visual Foxpro 6 中创建了一个光标,如下所示。
select month, memid, mname, bt, st, bh, sh, totk, toth, sum(totk*0.025)/100 as laga, sum(toth*0) as hchg, sum(totk*0.050)/100 as Tax ;
from abc2 ;
group by memid ;
order by 2 ;
into curs abc3
IF !USED("abc3")
USE abc3 in 0
ENDIF
select abc3
go top
do while not eof()
update abc3 set month = Thisform.txtReportHeader.Value
skip
ENDDO
“update abc3 set Month = Thisform.txtReportHeader.Value”行给了我一个错误,说我无法更新光标。如何使用文本字段“Thisform.txtReportHeader.Value”的值更新此列?
要使游标可更新,您需要使用 READWRITE 子句。即:
select * from myTable into cursor crsX READWRITE
但是,如果我没记错的话,READWRITE是在VFP7中引入的。如果是正确的,那么您应该使用老技巧使其可更新:
所以你的代码变成:
Select Month,memid,mname,bt,st,bh,sh,totk,toth,Sum(totk*0.025)/100 As laga,Sum(toth*0) As hchg,Sum(totk*0.050)/100 As Tax ;
from abc2 ;
group By memid ;
order By 2 ;
into Curs abc3_tmp ;
nofilter
USE DBF('abc3_tmp') IN 0 AGAIN ALIAS abc3
Update abc3 Set Month = Thisform.txtReportHeader.Value
* You don't need to select it to update it.
* And you also don't need a loop to do that
* If you wanted to limit the updated rows you would use a WHERE clause
*Select abc3
PS:虽然这种 SQL 在 VFP7 及更早版本中可以工作并且不会给出错误,但请尝试编写有效的 SQL,不要有任何歧义。也就是说,将所有非聚合列包含在分组依据中。如果不能,请三思,您的查询可能有问题。