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How to create a database in code

How to create a database in code

Question:
I was a VB programmer, until my recent shift to Delphi 2.0. How can I create a database in code?

Answer:
It depends on the type of database youwant to build. However, I can show you how to do it with a Paradox table.

What you have to do is declare a TTable variable, create an instance, thenwith the TTable’s FieldDefs property, add field definitions. Finally, you’llmake a call to CreateTable, and your table will be created. Here’s someexample code:

{ “Add” is the operative function here.  Add(const Name: string; DataType: TFieldType; Size: Word; Required: Boolean);}procedure CreateATable;var  tbl : TTable;begin  tbl := TTable.Create(Application);  with tbl do begin    Active := False;    DatabaseName := ‘‘;    TableName := ‘‘;    TableType := ttParadox;    with FieldDefs do begin      Clear;      Add(‘LastName’, ftString, 30, False);      Add(‘FirstName’, ftString, 30, False);      Add(‘Address1’, ftString, 40, False);      Add(‘Address2’, ftString, 40, False);      Add(‘City’, ftString, 30, False);      Add(‘ST’, ftString, 2, False);      Add(‘Zip’, ftString, 10, False);    end;    {Add a Primary Key to the table}    with IndexDefs do begin      Clear;      Add(‘Field1Index’, ‘LastName;FirstName’, [ixPrimary, ixUnique]);    end;        CreateTable; {Make the table}  end;end;
The procedure above makes a simple contact table, first by defining thefields to be included in the table, then creating a primary key. As you cansee, it’s a pretty straightforward procedure.

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