C ++ builder learn how to use stored procedures to prevent repeated login by the same person!

// Stored Procedure

/* If Exists (select name from sysobjects where name = 'addonearticle' and type = 'P') drop procedure addOneArticle */
/* If Exists (select name from sysobjects where name = 'session' and type = 'P') drop procedure Session */
/* Exec ('drop procedure dbo. session ')*/
Use highway_test_new
Set ANSI_NULLS ON
Set QUOTED_IDENTIFIER ON
If Exists (select id from dbo. sysobjects where id = object_id ('dbo. session') and type = 'P ')
BEGIN
Exec ('drop procedure dbo. session ')
Return
END

GO
Create procedure Session
@ Username varchar (50), @ I _result INT OUTPUT
AS
BEGIN
DECLARE @ v_ SQL varchar (200)
If object_id ('tempdb. DBO. # user' + @ username) is null
Begin
Set @ v_ SQL = 'create table # user' + @ username + '(username varchar (100 ))'
Exec (@ v_ SQL)
Set @ I _result = 0
End
Else
Set @ I _result = 1
End
//

Implementation Code

Bool verifyuserlogin (tmsconnection * pconn, tmsstoredproc * ptsp, ansistring strusername)
{
If (pConn = NULL | ptsp = NULL)
Return false;
Ptsp-> StoredProcName = "Session ";
Ptsp-> Connection = pConn;
Ptsp-> ParamByName ("@ username")-> AsString = strUserName;
Ptsp-> ExecProc ();
Int iRet;
IRet = ptsp-> ParamByName ("@ I _result")-> AsInteger;
If (iRet = 1) // the same user is logged on
{
Return false;
}
Else if (iRet = 0)
{
Return true;
}
Return false;
}