进展4GL查询可选

Question

“的突破”我有一个查询：

for each a where ..., 
    each b where ..., 
    each c where ..., 
     break by c.xxx by c.yyy by c.zzz. 

我需要的休息根据用户输入改变。

当我尝试定义查询：

def query qa for a, b, c. 
if ... then open qa for each a... (as above) 

那么它将不能编译，因为：

BREAK requires query be defined SCROLLING. (14283) 

我怎样才能“用破”设定的变量？

Answer 1

查找“query-prepare”。这就是让您完全自定义查询的神奇功能。

我今天早晨要编写这样的查询：

/* dyn.p 
*/ 

define variable tbl as character no-undo. 
define variable brk as character no-undo. 

define variable b as handle no-undo. 
define variable q as handle no-undo. 

tbl = "customer". 
brk = "state". 

create query q. 
create buffer b for table tbl. 

q:set-buffers(b). 

q:query-prepare("for each " + tbl + " break by " + brk). 
q:query-open. 
q:get-next(). 

do while q:query-off-end = false: 

    if q:first-of(1) then clear all. 

    display 
    b:buffer-field('CustNum'):buffer-value() 
    b:buffer-field('Name' ):buffer-value() 
    b:buffer-field('State' ):buffer-value() 
    with 
    down 
    . 

    down 1. 

    q:get-next(). 


end. 

return. 

运行上面的代码，反对“sports2000”。