SQL where only part of string is selected

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ASKER

I'm using an MS Access database.

ASKER

Found one..
SELECT Distinct MID(Bedrijven.Bedrijfsnaam,1,1) FROM Bedrijven Order by 1;

hmm, guess acces has similar function, not in mind yet

about the array,
you could declare the array also like

Buttons : array[ord('A')..ord('Z')] of TdxBarButton;

disable would the be

for i := ord('A') to ord('Z') do
Bottons[i].enabled := false;

iteration then

while not dataset.eof do
Buttons[ord(dataset.fields[0].asstring[1])].enabled := true;

meikl ;-)

oops, you found one :-))
not seen your comment before

ASKER

Where do I place the init array?

Buttons[0] := mbA
Buttons[1] := mbB
etc.

ASKER

One more question:
I also have a button with 0 (zero) which is used for all numeric values.
Ho to add that to the array etc.?

>Where do I place the init array?
best in the oncreate-event of your form,
this must be done only once

>also have a button with 0 (zero)
bad, in this case an array is useless or we have some empty slots

chars 0-9 are ords 48-57
chars A-Z are ords 65-90

seven slots would be unused (58-64) chars :;<=>?@

i think about that

meikl ;-)

ASKER

This code is looping forever. But we are getting there.
while not dataset.eof do
Buttons[ord(dataset.fields[0].asstring[1]) - 64].enabled := true

SOLUTION

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ASKER

So only the part with the 0 (zero) value remains.
The rest is working perfectly. Thanks a lot.

Stef

ASKER CERTIFIED SOLUTION

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ASKER

Yes that seems to be the solution if not the 0 (zero) should be set to True when any numeric value is the first character.
So 0,1,2,3,4,5,6,7,8 and 9.

SOLUTION

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ASKER

Well Meikl, you earned your point with ease.
Thank you.
Stef

glad you got it work :-))

good luck again

meikl ;-)

ASKER

Just some small adjustment:
The offset must be 64 after all.

// Deze procedure zet de verschillende filterknoppen aan waarvoor
// daadwerkelijk gegevens beschikbaar zijn.
With DM.QAlgemeenGebruik do
begin
Close;
SQL.Clear;
SQL.Add(' SELECT Distinct MID(Bedrijven.Bedrijfsnaam,1,1) AS BeginLetter FROM Bedrijven Order by 1 ');
Open;
end;
for i := 0 to 26 do
MyButton[i].enabled := false;
DM.QAlgemeenGebruik.First;
while not DM.QAlgemeenGebruik.Eof do
begin
if DM.QAlgemeenGebruik.Fields[0].asstring[1] in ['0'..'9'] then //change here
MyButton[0].enabled := true
else
MyButton[Ord(DM.QAlgemeenGebruik.Fields[0].asstring[1]) - 64].enabled := true; //offset should be 64
DM.QAlgemeenGebruik.Next; //missed this
end;