Hopefully someone knows about these things and will be able to give me a pointer. I'm presenting a grid to users to allow them to add or delete from a selection. Using Mike Skolnik's DBGrid I can have a tick box for selected rows. I've tried two approaches:
Companies.First;
while not Companies.Eof do begin
if CompanyIP.Find(Companies_ID.AsString, Junk) then CompanyList.SelectedRows.CurrentRowSelected := True;
Companies.Next;
end;

for Cntr := 0 to CompanyIP.Count - 1 do begin
if Companies.Locate('_ID', StrToIntDef(CompanyIP[Cntr], -1), []) then CompanyList.SelectedRows.CurrentRowSelected := True;
end;


The second is faster but still to slow. I have to use Locate rather than FindKey because the table is presented in company name sequence rather than id sequence. _ID is the primary key. DBGrids don't come with a beginupdate / end update. I'm using DisableControls at the start of the loop and enabling at the end.

Since its altering a visual control I can't push it off into a background thread (it may be possible but I don't know how).


All sensible suggestions will be warmly received (especially if they work).

Roy Lambert

Found one alternative which is a bit faster


Companies.Filter := '_ID IN ('+CompanyIP.CommaText+')';
Companies.Filtered:=True;
Companies.First;
while not Companies.Eof do begin
 CompanyList.SelectedRows.CurrentRowSelected := True;
 Companies.Next;
end;
Companies.Filtered:=False;
Companies.Filter:='';
Companies.First;


but still looking for something better.

Roy Lambert

Roy,

Where is the CompanyIP list coming from ?

--
Tim Young
Elevate Software
www.elevatesoft.com

Tim

>Where is the CompanyIP list coming from ?

Its a sorted stringlist. On opening the form its derived from a query

SELECT
LIST(CAST(_fkCompanies AS VARCHAR) USING #13) AS _CompanyIP,
LIST(CAST(_fkContacts AS VARCHAR) USING #13) AS _ContactIP
FROM Calls
WHERE
_fkProjects = :ProjectID


but then as companies are added to / deleted from the plan during the session the stringlist is adjusted.

Essentially its the approach I use to obtain allow a table to be used when I want to filter it in a way that involves JOINs

Roy Lambert

Roy,

<< Its a sorted stringlist. On opening the form its derived from a query >>

If you were to use a temporary table instead, you could leverage that to use
joins/sub-queries against it that might be a bit faster.

--
Tim Young
Elevate Software
www.elevatesoft.com

Tim

><< Its a sorted stringlist. On opening the form its derived from a query >>
>
>If you were to use a temporary table instead, you could leverage that to use
>joins/sub-queries against it that might be a bit faster.

Your memory is fading From my previous post

"Essentially its the approach I use to obtain allow a table to be used when I want to filter it in a way that involves JOINs"

Note the concept of filter in there. Until you let me use joins in a filter and keep table sensitivity I have to stick with this approach.

Roy Lambert

Roy
> Found one alternative which is a bit faster
>
>
> Companies.Filter := '_ID IN ('+CompanyIP.CommaText+')';
> Companies.Filtered:=True;
> Companies.First;
> while not Companies.Eof do begin
>   CompanyList.SelectedRows.CurrentRowSelected := True;
>   Companies.Next;
> end;
> Companies.Filtered:=False;
> Companies.Filter:='';
> Companies.First;
>
>
> but still looking for something better.

What takes the time, the setting of the filter or the iteration setting of the selected status?

John

John



>What takes the time, the setting of the filter or the iteration setting of the selected status?

Good question. A couple of weeks ago I might have been able to answer it. When I've finished messing with my accounts for the taxman I'll add some gettickcounts in and let you know.

Roy Lambert

Roy

> Good question. A couple of weeks ago I might have been able to answer it. When I've finished messing with my accounts
for the taxman I'll add some gettickcounts in and let you know.
>


It's not January 30th yet is it ?

John

John


The answer is - I'm confused

The form involved is used for planning which companies to add to a call plan. There are c7,000 companies. The form inherits from my standard company form but adds check boxes to a dbgrid. The initialisation puts ticks into the checkboxes for those companies that are already in the plan.

The problem splits into three parts

Part 1:
Populate the stringlist with IDs of the companies already in the plan - this is done using SELECT LIST..... and is pretty fast.

Part 2:
Use the above stringlist to set a filter on the companies table

Part 2:
walk through the filtered table ticking the checkboxes

I tried two different plans and ran it twice for each and here's where the fun starts

Plan 1 - 629 companies in the plan

Part 1 - 63, 47
Part 2 - 141,140
Part 3 - 483, 484

Plan 2 - 25 companies in the plan

Part 1 - 16, 32
Part 2 - 640, 531
Part 3 - 0, 15

These were done using a local database

So I then tried it out over my 100Mb LAN

Plan 1
Part 1 - 63,31,31
Part 2 - 32, 31, 31
Part 3 - 468, 328, 328

Plan 2
Part 1 - 436, 15, 16
Part 2 - 94, 109, 93
Part 3 - 0, 0, 0

Roy Lambert