firedac调用ORACLE的存储过程

firedac调用ORACLE的存储过程

EMB官方原文地址:http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Using_Oracle_with_FireDAC

笔者下面做的是中文翻译:

ORALCE的存储过程,相比MSSQL,多了一个PACKAGE(包)。

因此FIREDAC调用也稍有点不同。

ORACLE创建存储过程的样例脚本如下:

CREATE OR REPLACE PACKAGE FDQA_TestPack AS
  TYPE TVC2Tbl IS TABLE OF VARCHAR2(50) INDEX BY BINARY_INTEGER;
  PROCEDURE TestPLSQLArray(ATable in out TVC2Tbl);
END ADQA_testpack;
/

CREATE OR REPLACE PACKAGE BODY FDQA_TestPack AS
  PROCEDURE TestPLSQLArray(ATable IN OUT TVC2Tbl) IS
  BEGIN
    for i in ATable.First .. ATable.Last loop
      ATable(i) := '*' || ATable(i) || '*';
    end loop;
  END;
END FDQA_testpack;
/

 firedac调用ORACLE存储过程的代码如下:

FDStoredProc1.PackageName := 'MYPACK';
FDStoredProc1.StoredProcName := 'CLNTPROC';
FDStoredProc1.Prepare;
FDStoredProc1.ParamByName('AREC$CLIENT_ID').Value := 100;
FDStoredProc1.ParamByName('AREC$NAME').Value := 'Client 1';
FDStoredProc1.ParamByName('AREC$ACT').Value := True;
FDStoredProc1.ExecProc;

  调用ORACLE高级游标返回数据集

CREATE PROCEDURE TestRefCrs (ACrs1 IN OUT SYS_REFCURSOR, ACrs2 IN OUT SYS_REFCURSOR) AS
BEGIN
  OPEN ACrs1 FOR SELECT * FROM "Orders";
  OPEN ACrs2 FOR SELECT * FROM "Order Details";
END;

  用FDStoredProc调用:

FDStoredProc1.FetchOptions.AutoClose := False;
FDStoredProc1.StoredProcName := 'TESTREFCRS';
FDStoredProc1.Open;
// work with "Orders" table data
FDStoredProc1.NextRecordSet;
// work with "Order Details" table data
FDStoredProc1.Close;

  用FDQuery调用:

FDQuery1.FetchOptions.AutoClose := False;
FDQuery1.Open('BEGIN TestRefCrs(:p1, :p2); END;');
// work with "Orders" table data
FDQuery1.NextRecordSet;
// work with "Order Details" table data
FDQuery1.Close;

  

CREATE PROCEDURE TestDynCrs (ASQL IN VARCHAR2, ACrs OUT SYS_REFCURSOR) AS
BEGIN
  OPEN ACrs FOR ASQL;
END;

  调用:

FDQuery1.FetchOptions.AutoClose := False;
FDQuery1.SQL.Text := 'BEGIN TestDynCrs(:p1, :p2); END;';

FDQuery1.Params[0].AsString := 'SELECT * FROM "Orders"';
FDQuery1.Open;
// work with "Orders" table data
FDQuery1.Close;

FDQuery1.Params[0].AsString := 'SELECT * FROM "Order Details"';
FDQuery1.Disconnect;
FDQuery1.Open;
// work with "Order Details" table data
FDQuery1.Close;

  

Working with Oracle Nested Cursors

FireDAC supports CURSOR type columns in SELECT lists. There may be multiple CURSORs in the list. But a CURSOR nested into a CURSOR is not supported. FireDAC sets such columns to dtRowSetRef and creates a TDataSetField for them. To process their row sets, the application should use the TFDMemTable, and set its DataSetField property to a TDataSetField reference.

While the application navigates through the main dataset, the nested datasets will be automatically open and refreshed to provide the nested cursor records for a current record of the main dataset.

For examples, see the FireDAC\Samples\DBMS Specific\Oracle\NestedCursors demo.

转载于:https://www.cnblogs.com/hnxxcxg/p/9968701.html

一个使用ADO连接池的示例,演示了TADOStoredProc动态参数的使用,带重连机制 =================== unit UnitDemo; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; type TForm2 = class(TForm) Button1: TButton; procedure Button1Click(Sender: TObject); procedure FormCreate(Sender: TObject); procedure FormDestroy(Sender: TObject); private { Private declarations } public { Public declarations } end; var Form2: TForm2; //数据库服务器 gDBServer: String = '127.0.0.1'; //数据库名称 gDBName: String = 'master'; //数据库用户名 gDBUser: String = 'sa'; //密码 gDBPass: String = '2001'; implementation {$R *.dfm} uses ADODB, UnitADOConnectionPool; const CreateSQL = 'create procedure TestMyPool (@type sysname) '#13#10+ 'as'#13#10+ 'select * from sysobjects where xtype=@type'#13#10+ 'return @@rowcount'; DeleteSQL = 'if Exists(select 1 from sysobjects where xtype=N''P'' and name=N''TestMyPool'')'#13#10+ ' drop procedure TestMyPool'; var gPoolMan: TADOConnPoolMan = Nil; procedure TForm2.Button1Click(Sender: TObject); var ADOObject:TADOConnPoolObject; ADOStoredProc:TADOStoredProc; Running :Integer; I: Integer; begin //取得一个存储过程资源(含一数据库有效连接) ADOObject := gPoolMan.CreateSP('TestMyPool'); if ADOObject = Nil then //取得资源失败 Exit; try ADOStoredProc := ADOObject.ExecObject as TADOStoredProc; Running := 2;//允许重试(两次)操作,以便在操作失败之后达到重连 while Running>0 do begin Dec(Running); if ADOObject.NeedRefresh then begin//判断是否有重连标志(比如数据库断开等,可能需要进行重连) if Not ADOObject.Reconnect then Exit; ADOObject.NeedRefresh := Not ADOStoredProc.Parameters.Refresh; if ADOObject.NeedRefresh then Exit; end; for I := 1(*Zero is the *Result* Parameter*) to ADOStoredProc.Parameters.Count - 1 do begin //========================= //传递参数 ADOStoredProc.Parameters.Items[I].Value := 'U'; //========================= end; if Running 0 then try //执行存储过程 ADOStoredProc.Open; //执行存储过程成功,退出循环进入后续的数据处理 break; except On E:Exception do begin //执行失败非程序级的异常通常有两种可能: //1.数据库连接断开 //2.自适合的参数传递当中可能存储过程已更新,参与不一致 //设置重连标志 ADOObject.NeedRefresh := True; //=================== //这里记录数据库操作失败日志 //=================== end; end; Exit; end; //========================== //从ADOStoredProc当中读取记录 ShowMessage(IntToStr(ADOStoredProc.Parameters.ParamByName('Result').Value)); //========================== //关闭存储对象的资源 ADOStoredProc.Close; finally //调用结束,释放资源 ADOObject.Free; end; end; procedure TForm2.FormCreate(Sender: TObject); var ADOConn:TADOConnection; begin (****************BEGIN*******************) (*注:仅为测试准备 *) //初始化测试环境 ADOConn := Nil; if Not TADOConnPoolMan.ConnectADO( gDBServer,gDBUser,gDBPass,gDBName,true,ADOConn) then Exit; try ADOConn.Execute(DeleteSQL); ADOConn.Execute(CreateSQL); finally try ADOConn.Close; except end; ADOConn.Free; end; (*****************END********************) //初始化连接池 gPoolMan := TADOConnPoolMan.Create(gDBServer,gDBUser,gDBPass,gDBName,true); end; procedure TForm2.FormDestroy(Sender: TObject); var ADOConn:TADOConnection; begin //释放连接池 if Assigned(gPoolMan) then gPoolMan.Free; (****************BEGIN*******************) (*注:仅为测试准备 *) //清理测试环境 ADOConn := Nil; if Not TADOConnPoolMan.ConnectADO( gDBServer,gDBUser,gDBPass,gDBName,true,ADOConn) then Exit; try ADOConn.Execute(DeleteSQL); finally try ADOConn.Close; except end; ADOConn.Free; end; (*****************END********************) end; end.
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