Реферат: Как сделать двунаправленный запрос

s ascSelect="select ID, Name from NameList order by ID ASC"

s descSelect="select ID, Name from NameList order by ID DESC"

S ok=##class(%DynamicQuery).SQLPrepare(.descHandle,descSelect)

S ok=##class(%DynamicQuery).SQLExecute(.descHandle)

s descClose=descHandle

S ok=##class(%DynamicQuery).SQLPrepare(.ascHandle,ascSelect)

S ok=##class(%DynamicQuery).SQLExecute(.ascHandle)

s State=$li(ascHandle,1)

s ascClose=ascHandle

; идемна 4 шагавперед

s $li(ascHandle,1)=State

w "4 steps forward",!

f i=1:1:4 d

. d ##class(%DynamicQuery).SQLFetch(.ascHandle,.Row,.AtEnd)

. q:(AtEnd=1)!(Row="")

. s ID=$li(Row,1)

. s Name=$li(Row,2)

. w "ID="_ID_", Name="_Name,!

s State=$li(ascHandle)

; возвращаемся на 2 шага назад

s $li(descHandle,1)=State

w "2 steps backward",!

f i=1:1:2 d

. d ##class(%DynamicQuery).SQLFetch(.descHandle,.Row,.AtEnd)

. q:(AtEnd=1)!(Row="")

. s ID=$li(Row,1)

. s Name=$li(Row,2)

. w "ID="_ID_", Name="_Name,!

s State=$li(descHandle)