两种链接Sql数据库的语句

<appSettings>
    <add key="EnterpriseOAConnString" value="Data Source=.;Initial Catalog=EnterpriseOA;Persist Security Info=True;User ID=sa;Password=***;Max Pool Size=512;Connect Timeout=30;"/>
  </appSettings>
  <connectionStrings>
    <add name="EnterpriseOAConnString" connectionString="Data Source=.;Initial Catalog=EnterpriseOA;Persist Security Info=True;User ID=sa;Password=***;Max Pool Size=512;Connect Timeout=30;" providerName="System.Data.SqlClient"/>
  </connectionStrings>