property IsUniDirectional (problems with) No member is provided to
access proper
lazarus / 16-Databases

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lazguy · 2010-08-28 12:00

I saw in Delphi´s Guide that using the property IsUniDirectional can
improve the query´s speed. So I tried to use that. But I´m having
problems. When I build the program in Lazarus it causes the following
error:

ERROR: No member is provided to access property

Here is the code:

Code: [Select]    Con:=TZConnection.Create(nil);
    Con.Protocol:='sqlite-3';
    Con.Database:=extractfilepath(paramstr(0))+'control.s3db';
    Con.Connect;
    zqry:=TZQuery.Create(nil);
    zqry.Connection:=Con;
    zqry.IsUniDirectional := true;

( ... rest of code )


Code: [Select]    conAjustAux:=TSQLite3Connection.Create(nil);
    conAjustAux.DatabaseName:=TempFile1;
    tranAjustAux:=TSQLTransaction.Create(nil);
    tranAjustAux.DataBase:=conAjustAux;
    qryAjustAux:=TSQLQuery.Create(nil);
    conAjustAux.Open;
    qryAjustAux.Transaction:=tranAjustAux;
    qryAjustAux.DataBase:=conAjustAux;
    qryAjustAux.IsUniDirectional:=true;

(... rest of code )

Can someone help me?

Thank you in advance.

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webcss · 2010-08-28 14:27

Seems to be a bug. Which version (Lazarus/ fpc) do you use?

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lazguy · 2010-08-30 22:19

Thank you, webcss.

I am using Lazarus 0.9.28.2
FPC 2.2.4
SQLDBlaz 1.0.1
Zeos DBO 6.6.6

The database is SQLite 3

I will run on Windows and Linux.

Who can help me ?

Thank you very much in advance.

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Lacak2 · 2010-08-31 05:29

In case of sqlDB there is in db.pas in TDataSet defined property
IsUniDirectional as:

property IsUniDirectional: Boolean read FIsUniDirectional default
False;

You can see, that there is no write method, so you can not set
IsUniDirectional property.
May, be that this is bug, becasue there is unused protected method
SetUniDirectional.
It can be easy fixed:

property IsUniDirectional: Boolean read FIsUniDirectional write
SetUniDirectional default False;

IMHO you can report it as bug in bug tracker ...

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lazguy · 2010-08-31 13:00

Thank you Lacak2.

Maybe, if the protected method SetUniDirectional is unused, it is not
100% ready. So, if I use it, maybe it will not do what I expect it to
do. Don´t you think it is so much curious that both (Zeos and SQLDB)
causes the same error message? So maybe the problem is with FPC and
not only with SQLDB. In my opinion if the problem is only with SQLDB,
Zeos should work, but this is not true.
Maybe the method SetUniDirectional was intentionally deactivated due
to problems in FPC.

Who can help me?

Thank you very much in advance.

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Lacak2 · 2010-09-06 10:08

Quote from: lazguy on August 31, 2010, 03:00:19 pm Don´t you think it
is so much curious that both (Zeos and SQLDB) causes the same error
message?
Yes it is interesant ;-)

Quote from: lazguy on August 31, 2010, 03:00:19 pm So maybe the
problem is with FPC and not only with SQLDB. In my opinion if the
problem is only with SQLDB, Zeos should work, but this is not true.
Maybe the method SetUniDirectional was intentionally deactivated due
to problems in FPC.
I do not think, that problem is in FPC


Quote from: lazguy on August 31, 2010, 03:00:19 pmWho can help me?
In case of sqlDB you can post bug-report ... and wait how it will be
solved
In case of Zeos you can ask in Zeos forums ...

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lazguy · 2010-09-15 13:57

I have disappeared. I´m sorry, but i was busy.

Thank you, Lacak2.

I will make more researches.

If someone have the answer, please don´t be shy and help me.


Have a nice day!!