delphi - Getting database field value not working -


i using ado connection adoquery , dsr , adotable

i have database bookingnumbers field in table client.

i last bookingnumber in field , store in variable.

the booking number saved text on access.

so far have:

var snum : string; .... snum := datamodule1.tblclient['bookingnumber'].last;

but not working.

please help?

it not idea try , find maximum value of field navigating dataset, if dataset isn't ordered field in question. try instead:

function tform1.getmaxbookingnumber : integer; var   q : tadoquery; begin   q := tadoquery.create(nil);   q.connection := datamodule1.adoconnection1;  //  or whatever name of connection   try     q.sql.text := 'select max(bookingnumber) client';     q.open;     // `not isnull` in following allows table being empty     if not q.fields[0].isnull        result := q.fields[0].asinteger     else       result := -1;       q.free;   end; end;

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