Sqlite (v) Data insertion, update and deletion under Delphi FIREDAC

Add first on a blank form: tfdconnection, Tfdphyssqlitedriverlink, Tfdguixwaitcursor, Tfdquery, Tdatasource, TDBGrid (and associated at design time). You can also copy the contents of the following text box and paste it directly onto the form to quickly complete the add process:Object Dbgrid1:tdbgrid left = top = Width = 361 Height = 329 DataSource = DataSource1 TabOrder = 0 Ti Tlefont.charset = Default_charset Titlefont.color = Clwindowtext Titlefont.height = -11 titlefont.name = ' Tahoma ' Titlefont.style = [] End object Fdconnection1:tfdconnection left = top =-end Object FDPHYSSQLITEDRIVERLINK1:TF Dphyssqlitedriverlink left = 143 top = "End Object Fdguixwaitcursor1:tfdguixwaitcursor" Provider = ' Forms ' Left = The top = "End" Object fdquery1:tfdquery Connection = FDConnection1 left = 344 top = The End object DataSource1 : Tdatasource DataSet = FDQuery1 left = 420 top = On end object Button1:tbutton left = top = Width = 7 5 Height = Caption = ' Button1 ' taborder = 1 OnClick = Button1Click End object Button2:tbutton left = T OP = 136 Width = Height = Caption = ' Button2 ' TabOrder = 2 OnClick = Button2click End Object Button3:tbut ton left = top = The Width = Height = Caption = ' Button3 ' taborder = 3 OnClick = Button3click End Object Button4:tbutton left = top = Equal Width = Height = Caption = ' Button4 ' taborder = 4 OnClick = Button4click End

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Code:

{Create} procedure TForm1.FormCreate (Sender: TObject);
const
  dbPath = 'C: \ Temp \ SQLiteTest.sdb';
  strTable = 'CREATE TABLE MyTable (Id integer PRIMARY KEY AUTOINCREMENT, Name string (10), Age byte)'; // Id, Name, Age three fields // integer PRIMARY KEY AUTOINCREMENT: Increment field begin
  if FileExists (dbPath) then DeleteFile (dbPath);

  FDConnection1.ConnectionString: = 'DriverID = SQLite; Database =' + dbPath;
  FDConnection1.ExecSQL (strTable);

  FDQuery1.Open ('SELECT * FROM MyTable');
end;

{INSERT} procedure TForm1.Button1Click (Sender: TObject);
const
  strInsert = 'INSERT INTO MyTable (Name, Age) VALUES (: name,: age)'; //: name,: age The Format function is also handy.
  FDConnection1.ExecSQL (strInsert, ['AAA', 11]);
  FDConnection1.ExecSQL (strInsert, ['BBB', 22]);
  FDConnection1.ExecSQL (strInsert, ['CCC', 33]);
  FDConnection1.ExecSQL (strInsert, ['DDD', 44]);
  FDConnection1.ExecSQL (strInsert, ['EEE', 55]);
  FDQuery1.Refresh;
end;

{Update} procedure TForm1.Button2Click (Sender: TObject);
begin
  FDConnection1.ExecSQL ('UPDATE MyTable SET Age =: a WHERE Name =: n', [Random (100), 'AAA']);
  FDQuery1.Refresh;
end;

{Remove} procedure TForm1.Button3Click (Sender: TObject);
begin
  FDConnection1.ExecSQL ('DELETE FROM MyTable WHERE Age> 33');
  FDQuery1.Refresh;
end;

{Query the first result that meets the conditions} procedure TForm1.Button4Click (Sender: TObject);
var
  V: Variant;
begin
  V: = FDConnection1.ExecSQLScalar ('SELECT Age FROM MyTable WHERE Name =: x', ['BBB']);
  ShowMessage (V);
end;