Mysql，Oracle，Sqlserver数据库连接

.NET的Sqlserver连接串：

       'Dim constr As String = "Data Source=localhost;Initial Catalog=Hotel;user id =sa; password=123"

        '上面一句话可以在配置文件中获取

        Dim constr As String = Configuration.ConfigurationManager.ConnectionStrings("MyConnectionString").ConnectionString

        '建立连接

        Dim conn As SqlConnection = New SqlConnection()

        conn.ConnectionString = constr

        '创建命令对象

        Dim cmd As SqlCommand = New SqlCommand()

        cmd.Connection = conn

        cmd.CommandText = "select * from UserDetail where userName='" & namestr & "'"

        'DataReader是一种常用的数据库读取工具

        Dim reader As SqlDataReader

        Try

            conn.Open()

            reader = cmd.ExecuteReader()

            If reader.Read() Then

                If passstr = reader("userPwd") Then

                    MsgBox("登陆成功")

                Else

                    MsgBox("密码错误")

                End If

            Else

                MsgBox("没有此用户")

            End If

        Catch ex As Exception

            Throw New ApplicationException(ex.ToString())

        Finally

            reader.Close()

            conn.Close()

        End Try

    End Sub

配置文件中加上：

<connectionStrings >

<add name ="MyConnectionString" connectionString ="Data Source=localhost;Initial Catalog = Hotel; Integrated Security =SSPI"/>

</connectionStrings>

java的Sqlserver连接串：

Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");

Connection  conn=DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost:4720;databaseName=mydata","sa","root")

Mysql连接串：

Class.forName("com.mysql.jdbc.Driver");

conn=DriverManager.getConnection("jdbc:mysql://localhost/mydata?user=root&password=root");

或者："jdbc:mysql://localhost:3306/mydata","root","root"

Oracle链接：

Class.forName("oracle.jdbc.driver.OracleDriver");或者：new oracle.jdbc.driver.OracleDriver();

Connection conn = DriverManager.getConnection("jdbc:oracle:thin:localhost:1521:orcl", "scott","orcl");