有这样一个资料表﹕
a int
b int a b
0 1
0 1
0 2
0 2
0 3
0 3
0 3
要修改成﹕
a b
1 1
0 1
1 2
0 2
1 3
0 3
0 3
(如果有多個相同的B的值﹐就只修改其中一具A為1)
我只要修改a 请问这个SQL语句怎幺写
a int
b int a b
0 1
0 1
0 2
0 2
0 3
0 3
0 3
要修改成﹕
a b
1 1
0 1
1 2
0 2
1 3
0 3
0 3
(如果有多個相同的B的值﹐就只修改其中一具A為1)
我只要修改a 请问这个SQL语句怎幺写
thevalueofb=Edit1.text;
with TADOQuery.creat(self) do
begin
connection:=Adoconnection1;
//or connectionstring:='...';
sql.text:='update table set a='''+'1'+''''+' where a in (select top 1 a from table where b='''+Edit1.text+''''+')';
execsql;
end;
thevaluesofb=Edit1.text;
with TADOQuery.create(nil) do
begin
connection:=Adoconnection1;
//or connectionstring:='...';
sql.text:='select top 1 * from table where b='''+thevaluesofb
+'''';
open;
Edit;
Fieldbyname('a').asstring:='1';
post;
end;