ADO.net 中数据库连接方式(微软提供)-.NET教程,数据库应用

在msdn中，.net的数据库连接字符串都有详细的说明，我这里以代码范例的方式罗列一些，具体的每一项代表的意义可以参看msdn.

ado.net 中数据库连接方式(微软提供)

微软提供了以下四种数据库连接方式：

system.data.oledb.oledbconnection

system.data.sqlclient.sqlconnection

system.data.odbc.odbcconnection

system.data.oracleclient.oracleconnection

下面我们以范例的方式，来依次说明：

system.data.sqlclient.sqlconnection

常用的一些连接字符串(c#代码)：

sqlconnection conn = new sqlconnection( "server=(local);integrated security=sspi;database=pubs");

sqlconnection conn = new sqlconnection("server=(local)\netsdk;database=pubs;integrated security=sspi");

sqlconnection conn = new sqlconnection("data source=localhost;integrated security=sspi;initial catalog=northwind;");

sqlconnection conn = new sqlconnection(" data source=(local);initial catalog=xr;integrated security=sspi;

persist security info=false;workstation id=xurui;packet size=4096; ");

sqlconnection myconn = new system.data.sqlclient.sqlconnection("persist security info=false;integrated

security=sspi;database=northwind;server=mysqlserver");

sqlconnection conn = new sqlconnection( " uid=sa;pwd=passwords;initial catalog=pubs;data source=127.0.0.1;connect timeout=900");

更多字符串连接说明请看msdn：

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemdatasqlclientsqlconnectionclassconnectionstringtopic.asp

system.data.oledb.oledbconnection

常用的一些连接字符串(c#代码)：

oledbconnection conn = new oledbconnection(@"provider=microsoft.jet.oledb.4.0;data source=d:\myweb5\grocertogo.mdb");

oledbconnection conn = new oledbconnection(@"provider=microsoft.jet.oledb.4.0;password=;

user id=admin;data source=grocertogo.mdb;");

oledbconnection conn = new oledbconnection("provider=msdaora; data source=oracle8i7;persist security info=false;integrated security=yes");

oledbconnection conn = new oledbconnection("provider=microsoft.jet.oledb.4.0; data source=c:\bin\localaccess40.mdb");

oledbconnection conn = new oledbconnection("provider=sqloledb;data source=mysqlserver;integrated security=sspi");

更多字符串连接说明请看msdn：

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemdataoledboledbconnectionclassconnectionstringtopic.asp?frame=true

system.data.oracleclient.oracleconnection

常用的一些连接字符串(c#代码)：

oracleconnection myconn = new system.data.oracleclient.oracleconnection(

"data source=oracle8i;integrated security=yes");

更多字符串连接说明请看msdn：

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemdataoracleclientoracleconnectionclassconnectionstringtopic.asp?frame=true

system.data.odbc.odbcconnection

常用的一些连接字符串(c#代码)：

odbcconnection conn = new odbcconnection(

"driver={sql server};server=myserver;trusted_connection=yes;database=northwind;");

odbcconnection conn = new odbcconnection(

"driver={microsoft odbc for oracle};server=oracle8i7;

persist security info=false;trusted_connection=yes");

odbcconnection conn = new odbcconnection(

"driver={microsoft access driver (*.mdb)};dbq=c:\bin\nwind.mdb");

odbcconnection conn = new odbcconnection(

"driver={microsoft excel driver (*.xls)};dbq=c:\bin\book1.xls");

odbcconnection conn = new odbcconnection(

"driver={microsoft text driver (*.txt; *.csv)};dbq=c:\bin");

odbcconnection conn = new odbcconnection("dsn=dsnname");

更多字符串连接说明请看msdn：

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemdataodbcodbcconnectionclassconnectionstringtopic.asp?frame=true

其他厂商提供的数据库连接：

db2connection myconn = new ibm.data.db2.db2connection(

"database = sample;uid=<username>; pwd=<password>;");

db2connection myconn = new ibm.data.db2.db2connection("database = sample");

bdpconnection myconn = new borland.data.provider.bdpconnection("assembly=borl

and.data.mssql,version=1.1.0.0,culture=neutral,publickeytoken=91d62ebb5b0d1b1b;ve

ndorclient=sqloledb.dll;osauthentication=false;database=<database>;usernam

e=<user>;hostname=<host>;password=<password>;provider=mssql");

bdpconnection myconn = new borland.data.provider.bdpconnection("assembly=borl

and.data.db2,version=1.1.0.0,culture=neutral,publickeytoken=91d62ebb5b0d1b1b;ve

ndorclient=db2cli.dll;database=<database>;username=<user>;

password=<password>;provider=db2");

connection pooling

在sql server、ole db和.net框架结构中的data provider中，都提供了隐式的连接池连接支持。你可以在connectionstring中指定不同的参数值控制连接池的行为。比如下面的例子使ole db的连接池无效并自动地进行事务处理：

provider=sqloledb;ole db services=-4;data source=localhost;integrated security=sspi;

在sql server.net data provider中提供了以下参数设置控制连接池的行为：connection lifttime、connection reset、enlist、max pool size、min pool size和pooling