h_mohsenian
asked on
Make a Dynamic Database ( Use Alter Table Command from SQL in DELPHI )
I wana make a dynamic DataBase in my program. that means the structure of DataBase( Fields ) can be chnge with User.
This Change Can Make by Some Packages Like DataBase Desktop in Delphi , but I want the User Can Do It In my Program.
For Solving This Problem I used SQL Components, and Do somthing Like This :
Querry1.Close;
Querry1.SQL.Text := 'ALTER TABLE Country ADD column Products char(40)'; //
Querry1.Open;
but it makes Error!
if you Use This Command ('ALTER TABLE') please Help me and if think another way is better please tell me.
Thanks
h_mohsenian
This Change Can Make by Some Packages Like DataBase Desktop in Delphi , but I want the User Can Do It In my Program.
For Solving This Problem I used SQL Components, and Do somthing Like This :
Querry1.Close;
Querry1.SQL.Text := 'ALTER TABLE Country ADD column Products char(40)'; //
Querry1.Open;
but it makes Error!
if you Use This Command ('ALTER TABLE') please Help me and if think another way is better please tell me.
Thanks
h_mohsenian
ASKER CERTIFIED SOLUTION
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kretzschmar
btw. which database?
ASKER
I had a mistake in typing ,
I wrote This Code in my program:
Querry1.Close;
Querry1.SQL.Text := 'ALTER TABLE Country ADD column Products char(40)'; //
Querry1.Open;
And Querry1.Open & Query1.ExecSql have The Same Result.
I wrote This Code in my program:
Querry1.Close;
Querry1.SQL.Text := 'ALTER TABLE Country ADD column Products char(40)'; //
Querry1.Open;
And Querry1.Open & Query1.ExecSql have The Same Result.
ASKER
And About Your Question : 'which database? '
I Make This DataBase With DataBase Desktop in Delphi And The Database That I Used is 'Paradox 7'
I Make This DataBase With DataBase Desktop in Delphi And The Database That I Used is 'Paradox 7'
Hello
Alter table is DDL command, and it's better you use them from the database compoent not from dataset
Database1.Execute('ALTER TABLE Country ADD column Products char(40));
Mohammed
Alter table is DDL command, and it's better you use them from the database compoent not from dataset
Database1.Execute('ALTER TABLE Country ADD column Products char(40));
Mohammed
try this
Querry1.Close;
Querry1.SQL.Text := 'ALTER TABLE Country ADD Products char(40)'; //<-keyword coloumn is not needed
Querry1.ExecSQL; //is a must, never use open with an alter statement
meikl ;-)
Querry1.Close;
Querry1.SQL.Text := 'ALTER TABLE Country ADD Products char(40)'; //<-keyword coloumn is not needed
Querry1.ExecSQL; //is a must, never use open with an alter statement
meikl ;-)
sorry forget the last quote
Database1.Execute('ALTER TABLE Country ADD column Products char(40)');
also insure this table not used by any other dataset, and the database component connected property is true
Database1.Execute('ALTER TABLE Country ADD column Products char(40)');
also insure this table not used by any other dataset, and the database component connected property is true
ASKER
Dear kretzschmar,
as you told The key was Using 'Query1.ExecSql' , not 'Query1.Open' for 'ALTER TABLE'.
But!!!, I Have now a new problem:
when 'Query1.Close' executed 'Query1.Active' Set to 'False', and I 'Alter Table' Works without any problem,
but when I want to Set 'Query1.Active' Again ( Directly or by 'Query1.Open') for setting DBGrid , It Makes Error. What Can I Do?
Thanks
H_MOHSENIAN
as you told The key was Using 'Query1.ExecSql' , not 'Query1.Open' for 'ALTER TABLE'.
But!!!, I Have now a new problem:
when 'Query1.Close' executed 'Query1.Active' Set to 'False', and I 'Alter Table' Works without any problem,
but when I want to Set 'Query1.Active' Again ( Directly or by 'Query1.Open') for setting DBGrid , It Makes Error. What Can I Do?
Thanks
H_MOHSENIAN
ASKER
Dear mnasman ,
I Have Some problems when I Use Database1 ( Instead of a dataset, like TQuery Type ) .
Please Give Me Your E-Mail.
I Have Some problems when I Use Database1 ( Instead of a dataset, like TQuery Type ) .
Please Give Me Your E-Mail.
ASKER
Dear kretzschmar,
as you told The key was Using 'Query1.ExecSql' , not 'Query1.Open' for 'ALTER TABLE'.
But!!!, I Have now a new problem:
when 'Query1.Close' executed 'Query1.Active' Set to 'False', and I 'Alter Table' Works without any problem,
but when I want to Set 'Query1.Active' Again ( Directly or by 'Query1.Open') for setting DBGrid , It Makes Error. What Can I Do?
Thanks
H_MOHSENIAN
as you told The key was Using 'Query1.ExecSql' , not 'Query1.Open' for 'ALTER TABLE'.
But!!!, I Have now a new problem:
when 'Query1.Close' executed 'Query1.Active' Set to 'False', and I 'Alter Table' Works without any problem,
but when I want to Set 'Query1.Active' Again ( Directly or by 'Query1.Open') for setting DBGrid , It Makes Error. What Can I Do?
Thanks
H_MOHSENIAN
you must replace the sql-text with a select statement before opening the query
Ohh h_mohsenian
I'm late, i saw ur comment after u accept the answer
anyway, here's my email : nasman@mogaza.org
you are welcome to ask any time :)
Mohammed
I'm late, i saw ur comment after u accept the answer
anyway, here's my email : nasman@mogaza.org
you are welcome to ask any time :)
Mohammed
ASKER
dear kretzschmar,
you are right and I could solve my problem.
I think you are realy an expert .
Thanks alot
hamed
you are right and I could solve my problem.
I think you are realy an expert .
Thanks alot
hamed
ASKER
dear kretzschmar,
you are right and I could solve my problem.
I think you are realy an expert .
Thanks alot
hamed
you are right and I could solve my problem.
I think you are realy an expert .
Thanks alot
hamed
glad to helped you, hamed
good luck again
meikl ;-)
good luck again
meikl ;-)