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This test fails for 7496a/rev.14703 and trunk/rev.14704.

DEFINE TEMP-TABLE tmp1 NO-UNDO FIELD f1 AS INTEGER f2 AS CHARACTER INDEX idx1 IS UNIQUE f1.
CREATE tmp1. ASSIGN tmp1.f1 = 1 tmp1.f2 = 'one'.
CREATE tmp1. ASSIGN tmp1.f1 = 2 tmp1.f2 = 'two'.
CREATE tmp1. ASSIGN tmp1.f1 = 3 tmp1.f2 = 'three'.
RELEASE tmp1.

DEFINE QUERY q FOR tmp1.
QUERY q:FORWARD-ONLY = TRUE.
OPEN QUERY q FOR EACH tmp1.

GET FIRST q.
DO WHILE AVAILABLE(tmp1):
    MESSAGE tmp1.f1 tmp1.f2.
    GET NEXT q.
END.
GET LAST q.
MESSAGE tmp1.f1 tmp1.f2.

CLOSE QUERY q.

4GL Output:

1 one
2 two
3 three
Cannot LAST or PREV Query q when FORWARD-ONLY or -noautoreslist  or BREAK BY enabled. (12393)

7496a/rev.14703 and trunk/rev.14704 output:

1 one
2 two
3 three
Cannot LAST or PREV Query q when FORWARD-ONLY or -noautoreslist  or BREAK BY enabled. (12393)
** No tmp1 record is available. (91)
** No tmp1 record is available. (91)
? ?

Error 12393 is thrown when GET LAST is executed, the No record available error shows up when trying to display the values from an empty buffer. On second thought, there should be no problem with the cursor invalidation (the issue name can be changed into something more descriptive).

Another simpler test:

DEFINE TEMP-TABLE tmp1 NO-UNDO FIELD f1 AS INTEGER f2 AS CHARACTER INDEX idx1 IS UNIQUE f1.
CREATE tmp1. ASSIGN tmp1.f1 = 1 tmp1.f2 = 'one'.
CREATE tmp1. ASSIGN tmp1.f1 = 2 tmp1.f2 = 'two'.
CREATE tmp1. ASSIGN tmp1.f1 = 3 tmp1.f2 = 'three'.
// RELEASE tmp1. // <- buffer is not released anymore like in the first example

DEFINE QUERY q FOR tmp1.
QUERY q:FORWARD-ONLY = TRUE.
OPEN QUERY q FOR EACH tmp1.

GET LAST q.
MESSAGE tmp1.f1 tmp1.f2.

CLOSE QUERY q.

4GL output:

Cannot LAST or PREV Query q when FORWARD-ONLY or -noautoreslist  or BREAK BY enabled. (12393)

7496a/rev.14703 and trunk/rev.14704 output:

Cannot LAST or PREV Query q when FORWARD-ONLY or -noautoreslist  or BREAK BY enabled. (12393)
3 three

Is there a problem in changing recordOrShowError into recordOrThrowError?

Danut, do you have an example in which doing this change results in other regressions? If yes, can you post an example where recordOrThrowError is not right?

Alexandru Lungu wrote:

Is there a problem in changing recordOrShowError into recordOrThrowError?

Danut, do you have an example in which doing this change results in other regressions? If yes, can you post an example where recordOrThrowError is not right?

Here's an example where the execution is not interrupted by the exception:

DEFINE TEMP-TABLE tmp1 NO-UNDO FIELD f1 AS INTEGER.
DEFINE VARIABLE hq AS HANDLE NO-UNDO.

CREATE tmp1. ASSIGN tmp1.f1 = 1.
RELEASE tmp1.

DEFINE QUERY q FOR tmp1 SCROLLING.
hq = QUERY q:HANDLE.

hq:FORWARD-ONLY = TRUE.
hq:QUERY-PREPARE("FOR EACH tmp1").
hq:QUERY-OPEN().
hq:GET-LAST().
MESSAGE tmp1.f1.
hq:QUERY-CLOSE().

MESSAGE "test".

DELETE OBJECT hq.

Danut, can you attempt making the query forward-only after you prepare it, but before opening? Is there any difference?

Alexandru Lungu wrote:

Is the fact that in the second example the query is scrolling?

It doesn't matter if the query is scrolling.

Or maybe because the table has another structure (does the index or uniqueness matter)?

Structure/index/uniqueness does not matter, I tried to bring the example in #7722-3 to use the same structure but I get the same expected results from both.

Or maybe because the second query is dynamic?

This should be the case.

Danut, can you attempt making the query forward-only after you prepare it, but before opening? Is there any difference?

Yes, the dynamic query FORWARD-ONLY flag is set before the query is prepared, but this also doesn't change the results when it is done after it.

This might be strictly a difference between the types of queries used in both examples.

Alexandru Lungu wrote:

Can you extend your testing for other kind of errors thrown by QueryWrapper? For instance:

• can you check with other statements like get-first, get-next, get-prev and forward-only?
• can you check get-next, get-prev, get-last and get-first with a closed query that is either static or dynamic?
• can you attempt reposition on a closed query that is either static or dynamic?
• use GET-BUFFER-HANDLE, SET-BUFFERS, INDEX-INFORMATION, SKIP-DELETED-RECORD on either static or dynamic?
• can you use the ON ERROR, LEAVE clause for a wrapping block? Are the either static or dynamic queries honoring ON ERROR?

• GET-BUFFER-HANDLE will not be interrupted if a wrong parameter value is given, the same applies for INDEX-INFORMATION.
• I don't know how SET-BUFFERS should be tested, I did it together with GET-BUFFER-HANDLE where I tried to run the function with and without any buffers set. GET-BUFFER-HANDLE didn't throw any errors for a HANDLE with no buffers, it just printed ? for any given value (int/buffer name).
• When using ON ERROR UNDO, LEAVE with both static and dynamic queries the messages after the block are displayed. In the case of static queries, messages that are in the same DO ON ERROR UNDO, LEAVE block are not displayed after the error is thrown.
• Trying to access records after closing the a dynamic query doesn't interrupt the execution, while for static queries it is. Repositioning in a query acts in the same manner.
• Finally, I found a test which doesn't interrupt for both queries. It's a simple example where you run GET-NEXT 3 times on a temporary table with 2 records (scrolling/forward-only/preselect are not required to reproduce). Both tests display No record available is displayed and any message before closing the query.