FireDAC 下的 Sqlite [5] - 数据的插入、更新、删除

先在空白窗体上添加: TFDConnection、TFDPhysSQLiteDriverLink、TFDGUIxWaitCursor、TFDQuery、TDataSource、TDBGrid(并在设计时关联好).

你也可以复制下面文本框中的内容, 然后直接往窗体上贴, 以快速完成以上的添加过程:

object DBGrid1: TDBGrid
Left = 16
Top = 88
Width = 361
Height = 329
DataSource = DataSource1
TabOrder = 0
TitleFont.Charset = DEFAULT_CHARSET
TitleFont.Color = clWindowText
TitleFont.Height = -11
TitleFont.Name = 'Tahoma'
TitleFont.Style = []
end
object FDConnection1: TFDConnection
Left = 34
Top = 24
end
object FDPhysSQLiteDriverLink1: TFDPhysSQLiteDriverLink
Left = 143
Top = 24
end
object FDGUIxWaitCursor1: TFDGUIxWaitCursor
Provider = 'Forms'
Left = 260
Top = 24
end
object FDQuery1: TFDQuery
Connection = FDConnection1
Left = 344
Top = 24
end
object DataSource1: TDataSource
DataSet = FDQuery1
Left = 420
Top = 24
end
object Button1: TButton
Left = 400
Top = 88
Width = 75
Height = 25
Caption = 'Button1'
TabOrder = 1
OnClick = Button1Click
end
object Button2: TButton
Left = 400
Top = 136
Width = 75
Height = 25
Caption = 'Button2'
TabOrder = 2
OnClick = Button2Click
end
object Button3: TButton
Left = 400
Top = 192
Width = 75
Height = 25
Caption = 'Button3'
TabOrder = 3
OnClick = Button3Click
end
object Button4: TButton
Left = 400
Top = 240
Width = 75
Height = 25
Caption = 'Button4'
TabOrder = 4
OnClick = Button4Click
end
end

---

代码:

---

{建立}
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 三个字段
                                                                                                      //integer PRIMARY KEY AUTOINCREMENT: 自增字段
begin
  if FileExists(dbPath) then DeleteFile(dbPath);

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

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

{插入}
procedure TForm1.Button1Click(Sender: TObject);
const
  strInsert = 'INSERT INTO MyTable(Name, Age) VALUES(:name, :age)'; //:name, :age 的方式(后面还要以数组的方式给出相应的值), 这比字符串的 Format 函数还要方便.
begin
  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;

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

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

{查询符合条件的第一个结果}
procedure TForm1.Button4Click(Sender: TObject);
var
  V: Variant;
begin
  V := FDConnection1.ExecSQLScalar('SELECT Age FROM MyTable WHERE Name = :x', ['BBB']);
  ShowMessage(V);
end;

//:
select * from test where name = 'ABCDE' COLLATE NOCASE;
create table test (id Integer,name Text COLLATE NOCASE );

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