Solved

remove fields form ttable

Posted on 2002-07-01
8
205 Views
Last Modified: 2010-04-04
To obtain points you will create a ttable dynamically and set it to the ‘dbdemos’ alias, open the parts.db table. You will remove the field Cost.

You may have a static datasource and a dbgrid for testing that it actually worked.
0
Comment
Question by:God_Ares
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 5
  • 3
8 Comments
 
LVL 27

Expert Comment

by:kretzschmar
ID: 7121249
>you will create a ttable dynamically and set it to
>the ‘dbdemos’ alias

q : tquery;
begin
  q := tquery.create(self);
  try
    q.databasename := 'dbdemos';
    q.sql.text := 'create table Atable (field1 NUMBER, field2 CHAR(20))';
    q.execsql;
  finally
    q.free;
  end;
end;

just from head, other follows

meikl ;-)
0
 
LVL 27

Expert Comment

by:kretzschmar
ID: 7121251
>You will remove the field Cost.

q : tquery;
begin
 q := tquery.create(self);
 try
   q.databasename := 'dbdemos';
   q.sql.text := 'alter table parts drop costs'; //or alter table parts drop column costs
   q.execsql;
 finally
   q.free;
 end;
end;


just from head

meikl ;-)


0
 
LVL 27

Expert Comment

by:kretzschmar
ID: 7121253
forget the first one, i've misread it

btw. if you want to drop a field the table may not accessed/opened by anyone nor byself

meikl ;-)
0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 7

Author Comment

by:God_Ares
ID: 7121272
sorry kretzschmar it needs to be a ttable. I know it's possible to remove fields (not actually remove fields from db). if you put an ttable on the form and set a table you can 'hide' a field by double clicking on it. you'll get an editor an you may remove fields. that's what i want yet i had trouble figuring out how to do it.

procedeure button1
begin
  t := ttable.create(self);
  t.DatabaseName := 'Dbdemos';
  t.TableName := 'parts.db';
  .....
  your code here
  .....

  DataSource1.DataSet := t;

end;

onclose.
  t.free

0
 
LVL 27

Accepted Solution

by:
kretzschmar earned 100 total points
ID: 7121288
just set its visible-property to false like

table1.fieldbyname('costs').visible := false;

meikl ;-)
0
 
LVL 7

Author Comment

by:God_Ares
ID: 7121323
 t := ttable.create(self);
  t.DatabaseName := 'DBDEMOS';
  t.TableName := 'parts.db';

  t.Open; //<- Nessesary!!

  t.FieldByName('cost').Visible := 1=0;
0
 
LVL 27

Expert Comment

by:kretzschmar
ID: 7121328
yep, should work
0
 
LVL 7

Author Comment

by:God_Ares
ID: 7121336
yep that's it.
0

Featured Post

Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Creating an auto free TStringList The TStringList is a basic and frequently used object in Delphi. On many occasions, you may want to create a temporary list, process some items in the list and be done with the list. In such cases, you have to…
Introduction I have seen many questions in this Delphi topic area where queries in threads are needed or suggested. I know bumped into a similar need. This article will address some of the concepts when dealing with a multithreaded delphi database…
In a recent question (https://www.experts-exchange.com/questions/29004105/Run-AutoHotkey-script-directly-from-Notepad.html) here at Experts Exchange, a member asked how to run an AutoHotkey script (.AHK) directly from Notepad++ (aka NPP). This video…
Finding and deleting duplicate (picture) files can be a time consuming task. My wife and I, our three kids and their families all share one dilemma: Managing our pictures. Between desktops, laptops, phones, tablets, and cameras; over the last decade…

731 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question