break - 带有可选“break by”的进度 4GL 查询

Question

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.

我需要休息时间根据用户输入而变化。

当我尝试定义查询时：

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

那么它不会编译，因为：

BREAK requires query be defined SCROLLING. (14283) 

如何为“break by”设置变量？

Answer 1

查找“查询准备”。这就是让您完全自定义查询的魔力。

我今天早上碰巧在写这样一个查询：

/* 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.

针对“sports2000”运行上面的代码。