FIREDAC FDConnection 连接池 连接串

一、FDConnection 连接池

http://docs.embarcadero.com/products/rad_studio/firedac/frames.html?frmname=topic&frmfile=Defining_Connection.html

http://docwiki.embarcadero.com/RADStudio/XE8/en/Defining_Connection_%28FireDAC%29

http://docwiki.embarcadero.com/RADStudio/Berlin/en/Multithreading_(FireDAC)

FDManager()->ConnectionDefs->ConnectionDefByName("")

FDManager.ConnectionDefs.ConnectionDefByName(cbDB.Text).Params.Pooled := True

oConn.ConnectionDefName;

FDConnection1->Params->Pooled;

$(FDHOME)\FDConnectionDefs.ini

D:\Users\Public\Documents\Embarcadero\Studio\FireDAC\FDConnectionDefs.ini

D:\Users\Public\Documents\Embarcadero\Studio\16.0\Samples\Object Pascal\Database\FireDAC\Samples\Comp Layer\TFDConnection\Pooling

从这个官方例子看出使用连接池比不使用连接池的效率提高4倍。

http://www.cnblogs.com/zhenfei/p/4105515.html

1）FDConnectionDefs.ini文件

[MSSQL_Demo]

DriverID=MSSQL

Server=127.0.0.1

Database=Northwind

User_Name=sa

Password=

MetaDefSchema=dbo

MetaDefCatalog=Northwind

ExtendedMetadata=True

以上代码存为FDConnectionDefs.ini文件放到当前exe目录下，程序会自己找到。小节名称与ConnectionDefByName参数一致。

this->FDManager1->ConnectionDefFileName = "FDConnectionDefs.ini";

this->FDManager1->ConnectionDefs->ConnectionDefByName("MSSQL_Demo")->Params->Pooled = true;

考虑到安全性，密码需要加密，所以建议用方法2或3。

2）代码动态创建IFDStanConnectionDef

uses
  FireDAC.Comp.Client, FireDAC.Stan.Intf;
var
  oDef: IFDStanConnectionDef;
begin
  oDef := FDManager.ConnectionDefs.AddConnectionDef;
  oDef.Name := 'MSSQL_Connection';
  oDef.DriverID := 'MSSQL';
  oDef.Server := '127.0.0.1';
  oDef.Database := 'Northwind';
  oDef.OSAuthent := True;
  oDef.MarkPersistent;
  oDef.Apply;
  .....................
  FDConnection1.ConnectionDefName := 'MSSQL_Connection';
  FDConnection1.Connected := True;

3）连接参数

var
  oParams: TStrings;
begin
  oParams := TStringList.Create;
  oParams.Add('Server=127.0.0.1');
  oParams.Add('Database=Northwind');
  oParams.Add('OSAuthent=Yes');
  FDManager.AddConnectionDef('MSSQL_Connection', 'MSSQL', oParams);
  .....................
  FDConnection1.ConnectionDefName := 'MSSQL_Connection';
  FDConnection1.Connected := True; c++  FDManager()->AddConnectionDef("", "", para);其他

FDManager.ConnectionDefFileName := ExtractFilePath(Application.ExeName) + 'myconndef.ini';
FDManager.ConnectionDefFileAutoLoad := True;
oConn := TFDConnection.Create(nil);
oConn.ConnectionDefName := 'myconn';
oConn.Connected := True;

Create Connection def

void __fastcall TForm35::Button5Click(TObject *Sender)
{
    TStrings *para;
    para = new TStringList();
    para->Add("Server=192.168.1.1");
    para->Add("Database=db");
    para->Add("User_Name=sa");
    para->Add("Password=123");

    FDManager()->AddConnectionDef("sqlPTT", "MSSQL", para);

    FDConnection1->ConnectionDefName = "sqlPTT";
    Label1->Caption = this->FDConnection1->ResultConnectionDef->BuildString();
    delete para;

    int startTime = GetTickCount();
    for (int i = 0; i < 10; i++)
    {
        this->Button1->Click();
    }
    Caption = (GetTickCount() - startTime) / 1000.0;
}

use pool

void __fastcall TForm35::Button1Click(TObject *Sender)
{
    TFDConnection *con;
    con = new TFDConnection(NULL);
    con->ConnectionDefName = FDConnection1->ConnectionDefName;

    TFDQuery *qry;
    qry = new TFDQuery(NULL);
    qry->Connection = con;
    qry->SQL->Text = "select count(*) from tt";
    qry->Open();
    con->Close();

    delete con;
    delete qry;

}

连接池比普通连接块4倍！

连接字符串ConnectString

mssql带端口号

Server={127.0.0.1,9433};User_Name=sa;;Password=123;Database=dbname;DriverID=MSSQL

Name=Unnamed;Database=mydb;User_Name=sa;Password=123;Server=127.0.0.1;DriverID=MSSQL

FDConnection1.ConnectionString := 'DriverID=MSSQL;Server=127.0.0.1;Database=Northwind;User_name=sa;Password=123;';Database=car;User_Name=sa;Password=;Server=127.0.0.1,9433;DriverID=MSSQLmysqlDatabase=testdata;User_Name=root;Password=root;Server=127.0.0.1;DriverID=MySQL;CharacterSet=utf8sqlite:Database=D:\msdb.db;DriverID=SQLite执行十条sql语句性能比较。1、一个连接打开，不关闭，耗时0.184ms2、使用连接池，耗时0.265ms3、不使用连接池，0.71ms oracle连接字符串ip地址输入10.0.0.2:1521/orcl  FDConnection1.Params.DriverID:='SQLite';  FDConnection1.Params.Database := 'Demo.db';以前ADO连接ADOConstr = PromptDataSource(0, ADOConnection1->ConnectionString);DBF连接串Provider = Microsoft.Jet.OLEDB.4.0 ;Data Source ={0};Extended Properties=dBASE IVSQLite连接字符串Name=Unnamed;Database=E:\Bin\posdata.sqlite;DriverID=SQLiteMYSQL连接串Name=Unnamed;Database=tData;User_Name=root;Password=root;Server=127.0.0.1;DriverID=MySQL;CharacterSet=utf8;Port=3306ADO连接字符串

Provider=SQLOLEDB.1;Password=123;Persist Security Info=True;User ID=sa;Initial Catalog=mydb;Data Source=127.0.0.1

ADOExcel

ADOConnectionExcel.ConnectionString:='Provider=Microsoft.Jet.OLEDB.4.0;Data Source='+                            EXLfilename+';Extended Properties=excel 8.0;'+                            'Persist Security Info=false;'                            ; --ORACLEDriverID=OraDatabase=(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521)) )  (CONNECT_DATA = (SERVICE_NAME = orcl)))User_Name=DI_EHRPassword=neusoftAuthMode=NormalCharacterSet=UTF8DB2http://docwiki.embarcadero.com/RADStudio/Rio/en/Connect_to_IBM_DB2_Server_(FireDAC)

Use Cases

• Connect to DB2 using the existing database alias:

DriverID=DB2
Alias=addemo
User_Name=db2admin
Password=mypwd
MetaDefSchema=db2admin

• Connect to DB using full connection information:

DriverID=DB2
Server=127.0.0.1
Database=addemo
Port=50000
Protocol=TCPIP
User_Name=db2admin
Password=mypwd
MetaDefSchema=db2admin

FireDAC EXCEL

FDConnection.Params.Clear;
FDConnection.Params.Add('Database=<myfile>');
FDConnection.Params.Add('ODBCDriver={Microsoft Excel Driver (*.xls, *.xlsx, *.xlsm, *.xlsb)}');
FDConnection.Params.Add('DriverID=ODBC');
FDConnection.Params.Add('ODBCAdvanced=HDR=No');
FDConnection.Open;或者字符串

'ODBCDriver={Driver do Microsoft Excel(*.xls)};Database=E:\2001aa.xls;DataSource=Excel Files;DriverID=ODBC'ADO MSSQL      Provider=SQLOLEDB.1;Password=123;Persist Security Info=True;User ID=sa;Initial Catalog=MYDB;Data Source=127.0.0.1C++        ADOConstr = "Provider=SQLOLEDB.1;Password=%S;" "Persist Security Info=True;User ID=%S;" "Initial Catalog=%S;" "Data Source=%S";        ADOConstr = Format(ADOConstr,            ARRAYOFCONST(((String)Password, (String)UserID, (String)DBName, (String)HostName)));

原文链接: https://www.cnblogs.com/cb168/p/4748801.html

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