[progress Communities] [progress Openedge Abl] Forum Post: Buffers Not Released In Dynamic...

[Patrick Tingen]

In one of my programs I was looking for the table a certain list of fields belonged to. To translate this to the sports db, imagine this list of fields: "order-num,promise-date". There is only one table in the sports db that contains both fields and that is 'order'. Some fields might occur in more than one table, but in our database this is a bit easier since all field names are unique (Mfg/Pro database). Since there can be invalid entries in the list of fields, I try to ignore those and I set the table to the first one that has 2 hits from the list. When I try to solve this dynamically (I have more than 1 database) I run into the problem that a secondary dynamic buffer is not released on consecutive iterations (both v10 and v11). So on iteration 2 the program tries to find the field 'hello-world', which obviously does not exist. But the _file buffer that was found in the previous iteration is still available. Below is a reproduction on the sports db. My question is: is this expected / desired behaviour? At least it is not intuitive. DEFINE VARIABLE cWhere AS CHARACTER NO-UNDO. DEFINE VARIABLE hQuery AS HANDLE NO-UNDO. DEFINE VARIABLE hField AS HANDLE NO-UNDO. DEFINE VARIABLE hFile AS HANDLE NO-UNDO. DEFINE VARIABLE cFields AS CHARACTER NO-UNDO INITIAL 'promise-date,hello-world'. DEFINE VARIABLE i AS INTEGER NO-UNDO. CREATE BUFFER hFile FOR TABLE "_File". CREATE BUFFER hField FOR TABLE "_Field". DEFINE VARIABLE cField AS CHARACTER NO-UNDO. CREATE QUERY hQuery. hQuery:SET-BUFFERS(hField,hFile). /* Dynamic solution */ DO i = 1 TO NUM-ENTRIES(cFields): cWhere = SUBSTITUTE( "FOR EACH _field WHERE _field._field-name = '&1', FIRST _file OF _field", ENTRY(i,cFields)). hQuery:QUERY-PREPARE(cWhere). hQuery:QUERY-OPEN(). hQuery:GET-FIRST(NO-LOCK). IF hFile:AVAILABLE THEN MESSAGE 'Dynamic Query' SKIP(1) i ENTRY(i,cFields) '/' hFile::_file-name VIEW-AS ALERT-BOX INFO BUTTONS OK. hQuery:QUERY-CLOSE(). END. /* Static solution */ DO i = 1 TO NUM-ENTRIES(cFields): FOR EACH _field WHERE _field._field-name = ENTRY(i,cFields) , FIRST _file OF _field: MESSAGE 'Static Query' SKIP(1) i ENTRY(i,cFields) '/' _file._file-name VIEW-AS ALERT-BOX INFO BUTTONS OK. END. END.

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