Entry

Delphi: Database: Sql: Query: Create: Simple: How to create a simple SQL query in Borland Delphi?

Aug 22nd, 2003 17:28
Knud van Eeden,

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--- Knud van Eeden - 23 August 2003 - 01:55 am -----------------------

Delphi: Database: Sql: Query: Create: Simple: How to create a simple 
SQL query in Borland Delphi?

Steps: Overview:

1. Running your SQL query via component property 'SQL'

2. Running your SQL query programmatically via Delphi source code

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Steps: Worked out:

1. Running your SQL query via component property 'SQL':

 1.1. put a component 'TQuery' on the form (from palette 'BDE')
     -double click on the property 'SQL', and fill in your SQL query

       e.g.

        SELECT COUNT( * ) FROM mytablename;

    -set property 'Active' = true

    -set property 'DatabaseName' to one of your aliases for databases
                                 (e.g. 'mydatabasealias')

http://www.faqts.com/knowledge_base/view.phtml/aid/23861/fid/175

 1.2. put a component 'TDataSource' on the form (from palette 'Data 
Access')

     -set property 'DataSet' = Query1

 1.3. Put a component 'dBGrid' on the form (from palette 'Data 
Controls')

     -set property 'DataSource' = datasource1

 1.4. Put a component 'dBNavigator' on the form (from palette 'Data 
Controls')

     -set property 'DataSource' = datasource1

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This could for example show the output from applying this given SQL 
query to
the given database table, in the dbgrid:

     +---------------------------------------------------+
     |count (*) |                                        |
     |----------|                                        |
     |1         |                                        |
     |----------+                                        |
     +---------------------------------------------------+

---
---

Note:

To run another query, you can change the text in the property 'Sql' on
the component.

For example change this in:

        SELECT * FROM mytablename;

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2. Running your SQL query programmatically via Delphi source code:

If you want to input the SQL query via your Delphi source code,
you could for example put a button on your form:

 2.1 Double click on this button, and put in there the following
     text:

     procedure TForm1.Button1Click(Sender: TObject);
     var s : string;
     begin
      s := 'SELECT COUNT( * ) FROM mytablename;';
      Query1.Active := false;
      Query1.Sql.Clear;
      Query1.Sql.Text := s;
      Query1.ExecSQL;
      Query1.Active := true;
     end;

 2.2 Run and compile this, then press the button.

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This could for example show the output from applying this given SQL 
query to
the given database table, in the dbgrid:

     +---------------------------------------------------+
     |count (*) |                                        |
     |----------|                                        |
     |1         |                                        |
     |----------+                                        |
     +---------------------------------------------------+

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