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Author Firebird-Blob-Editor...
Angelo Bocchini

2005-12-21, 7:23 am

Hallo,
I have a problem with a blob field with Firebird.
If I have:

( look at select...)

this.ANA1 = new QUERY()
this.ANA1.parent = this
with (this.ANA1)
left = 45.1429
top = 7.0455
database = form.test1
sql = "select * from ANA ORDER BY DITTA" <<<<<<<<<<<<<<
active = true
endwith

and in a form I have an editor linked to the field Note,
(that's a blob field), as I write in the editor and Iskip,
(form.rowset.next()), it's all OK.

instead if:

this.ANA1 = new QUERY()
this.ANA1.parent = this
with (this.ANA1)
left = 45.1429
top = 7.0455
database = form.test1
sql = "select * from ANA " <<<<<<<<<<<<<<<<<<<
active = true
endwith

, so without ORDER BY
as I write in the editor, and I skip I have an error like

At beginning of table

and there is nothing I can do. I must close all.

Do someone know wy ????

thank in advance,
ciao
Angelo Bocchini
GENESI
angelo@genesigroup.it


*Lysander*

2005-12-21, 7:23 am

In article <tKs3KPhBGHA.1448@news-server>, genesi@genesigroup.it says...

> Do someone know wy ????


BDE has problems with handling the pointers to the memo-data.
But this is only with _DATALINKED_ editors.

This is not a dBase-problem, because it also happens in Delphi, when=20
using BDE or dBExpress-components (ADO does not report this error).

You _CAN_ try to increase the values for "BLOBs to cache" and for=20
"rowset size" in the BDE-Alias for your Firebird aliases.

In some cases this will help, but the general recommendation is to NOT=20
use datalinked editors to memo-fields.
=20

--=20
ciao,
Andr=E9
Jun S. Pomer

2005-12-21, 11:23 am

Hi,

I use Blob field with Subtype text with no problem even it is datalinked.

Regards André.

Hope it helps.

Jun


"*Lysander*" <nobody@nowhere.com> wrote in message
news:MPG. 1e1362aa4d6045799899
b1@news.dbase.com...
In article <tKs3KPhBGHA.1448@news-server>, genesi@genesigroup.it says...

> Do someone know wy ????


BDE has problems with handling the pointers to the memo-data.
But this is only with _DATALINKED_ editors.

This is not a dBase-problem, because it also happens in Delphi, when
using BDE or dBExpress-components (ADO does not report this error).

You _CAN_ try to increase the values for "BLOBs to cache" and for
"rowset size" in the BDE-Alias for your Firebird aliases.

In some cases this will help, but the general recommendation is to NOT
use datalinked editors to memo-fields.


--
ciao,
André


*Lysander*

2005-12-21, 11:23 am

In article <XPS460kBGHA.1800@news-server>, jspomer@softworks.com.ph=20
says...
> Hi,
>=20
> I use Blob field with Subtype text with no problem even it is datalinked.


Thanks for the info.

I do not use datalinked memos at all, so I don't have experience in=20
that. I was taking this info from the BDE-group on the Borland-servers.

As I understand, this problem does not occur always, but only after=20
certain amount of scrolling BACK through the rowset.=20

Do your datalinked memofields have a navigation-control attached on=20
themselves or on the form, which makes it possible to click 30 times or=20
so "back" 1 record, and from record to record make any changes to the=20
value of the memofield?

Does it work without problem?
Because this was described by Borland as a problem.

--=20
ciao,
Andr=E9
Jun S. Pomer

2005-12-21, 1:23 pm

Hi André,

I do not received any complains/error regarding memofields. It is attached
in the navigator control.

BTW, Its true that I do not need a lot of index for searching. I use order
by with accending, decending options.

Thanks.

Jun

"*Lysander*" <nobody@nowhere.com> wrote in message
news:MPG. 1e13ad029c51e0c69899
b3@news.dbase.com...
In article <XPS460kBGHA.1800@news-server>, jspomer@softworks.com.ph
says...
> Hi,
>
> I use Blob field with Subtype text with no problem even it is datalinked.


Thanks for the info.

I do not use datalinked memos at all, so I don't have experience in
that. I was taking this info from the BDE-group on the Borland-servers.

As I understand, this problem does not occur always, but only after
certain amount of scrolling BACK through the rowset.

Do your datalinked memofields have a navigation-control attached on
themselves or on the form, which makes it possible to click 30 times or
so "back" 1 record, and from record to record make any changes to the
value of the memofield?

Does it work without problem?
Because this was described by Borland as a problem.

--
ciao,
André


*Lysander*

2005-12-21, 1:23 pm

In article <5lWhlnlBGHA.1448@news-server>, jspomer@softworks.com.ph=20
says...

> I do not received any complains/error regarding memofields. It is=20

attached
> in the navigator control.
>=20
> BTW, Its true that I do not need a lot of index for searching. I use orde=

r
> by with accending, decending options.


Thanks for the feedback, in both topics.

About the memofields it will be good to know for others, who are using=20
datalinked memos.
I hope that Angelo can solve his problem.

About your test that you need less indexes this is very good=20
confirmation. My tests were showing the same effect. This makes=20
switching to Firebird much easier, because you do not need to worry=20
about too many indexes with the same name.
dBase-tables do not complain when you have two indexes with the same=20
name on two different tables.


--=20
ciao,
Andr=E9
*Lysander*

2005-12-21, 1:23 pm

In article <5lWhlnlBGHA.1448@news-server>, jspomer@softworks.com.ph=20
says...
> Hi Andr=E9,
>=20
> I do not received any complains/error regarding memofields. It is attache=

d
> in the navigator control.


But you are using the tables "as they are" (mixed/natural order) or are=20
you using any "order by", because Angelo already narrowed the error to=20
such cases when not using any index and not any "order by".

--=20
ciao,
Andr=E9
*Lysander*

2005-12-21, 1:23 pm

In article <tKs3KPhBGHA.1448@news-server>, genesi@genesigroup.it says...

> , so without ORDER BY
> as I write in the editor, and I skip I have an error like
>=20
> At beginning of table
>=20
> and there is nothing I can do. I must close all.
>=20
> Do someone know wy ????


Which indexes are on the ANA-table?
Every Firebird-table _should_ have a primary key.
If the ANA-table does not have one, try to create one and see if this=20
will help.
If not, also try the changes in the BDE-Alias as suggested earlier.

Select "*" without "order by" opens the table _automagically_ with=20
primary key index.=20
Select "field1, field2, field3,..." without "order by" opens the table=20
withOUT any index.


--=20
ciao,
Andr=E9
Angelo Bocchini

2005-12-21, 1:23 pm

Andre',
there is a primary key ( the field DITTA).
( the TEST table has only two fields, DITTA (char)
and NOTE (blob))

The problem occours ONLY after modifing
trough the editor the memo field, and moving
to another record.

ciao

--
Angelo Bocchini
GENESI
angelo@genesigroup.it
"*Lysander*" <nobody@nowhere.com> ha scritto nel messaggio
news:MPG. 1e13bbbd537a0a799899
b6@news.dbase.com...
In article <tKs3KPhBGHA.1448@news-server>, genesi@genesigroup.it says...

> , so without ORDER BY
> as I write in the editor, and I skip I have an error like
>
> At beginning of table
>
> and there is nothing I can do. I must close all.
>
> Do someone know wy ????


Which indexes are on the ANA-table?
Every Firebird-table _should_ have a primary key.
If the ANA-table does not have one, try to create one and see if this
will help.
If not, also try the changes in the BDE-Alias as suggested earlier.

Select "*" without "order by" opens the table _automagically_ with
primary key index.
Select "field1, field2, field3,..." without "order by" opens the table
withOUT any index.


--
ciao,
André


*Lysander*

2005-12-22, 7:23 am

In article <fEKUm#lBGHA.1300@news-server>, genesi@genesigroup.it says...
> Andre',
> there is a primary key ( the field DITTA).
> ( the TEST table has only two fields, DITTA (char)
> and NOTE (blob))
>=20
> The problem occours ONLY after modifing
> trough the editor the memo field, and moving
> to another record.


This is exactly how problems are described by Borland.
This happens with using BDE and ANY SQL-server, not only with Firebird.

Try changing the settings for "blobs to cache" and for "rowset size".

It is not a common/normal setup to scroll through a table with a form,=20
if the table has only one memo-field.

The primary key field should have no meaning at all, and - in fact -=20
should not even be seen by the user, and of course not be editable.

--=20
ciao,
Andr=E9
Jun S. Pomer

2005-12-27, 3:23 am

Hi André,

I used "order by/order by <fields> desc" with no problem.

Happy New Year!

Thanks.

Jun


"*Lysander*" <nobody@nowhere.com> wrote in message
news:MPG. 1e13bafabc8517e19899
b5@news.dbase.com...
In article <5lWhlnlBGHA.1448@news-server>, jspomer@softworks.com.ph
says...
> Hi André,
>
> I do not received any complains/error regarding memofields. It is attached
> in the navigator control.


But you are using the tables "as they are" (mixed/natural order) or are
you using any "order by", because Angelo already narrowed the error to
such cases when not using any index and not any "order by".

--
ciao,
André


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