Access VBA connection to test existence of SQL Server -


i have access application needs connect 1 of several possible sql servers (i.e., connect linked tables) , have list of possible sql server instance names. when application launches, needs go see of possible servers available. considering sluggishness of solutions using sqlbrowseconnect or netserverenum, i'm wondering if there clean , fast way 'ping' sql server based on name.

we use pass-through query, verifyconnection, opens small table.

the test alters connection , checks if can read table:

public function issqlserver( _     byval testnewconnection boolean, _     optional byval hostname string, _     optional byval database string, _     optional byval username string, _     optional byval password string, _     optional byref errnumber long) _     boolean      const cstrquery     string = "verifyconnection"      dim dbs             dao.database     dim qdp             dao.querydef     dim rst             dao.recordset      dim booconnected    boolean     dim strconnect      string     dim strconnectold   string     dim boocheck        boolean      set dbs = currentdb     set qdp = dbs.querydefs(cstrquery)      if hostname & database & username & password = ""         if testnewconnection = false             ' verify current connection.             boocheck = true         else             ' fail. no check needed.             ' new connection cannot checked empty parameters.         end if     else         strconnectold = qdp.connect         strconnect = connectionstring(hostname, database, username, password)         if strconnect <> strconnectold             if testnewconnection = false                 ' fail. no check needed.                 ' tables connected database.             else                 ' check new connection.                 qdp.connect = strconnect                 boocheck = true             end if         else             ' check current connection.             strconnectold = ""             boocheck = true         end if     end if      on error goto err_issqlserver      ' perform check of new connection or verify current connection.     if boocheck = true         set rst = qdp.openrecordset()         ' tried connect ...         if errnumber = 0             if not (rst.eof or rst.bof)                 ' success.                 booconnected = true             end if             rst.close         end if          if strconnectold <> ""             ' restore old connection parameters.             qdp.connect = strconnectold         end if     end if      set rst = nothing     set qdp = nothing     set dbs = nothing      issqlserver = booconnected  exit_issqlserver:     exit function  err_issqlserver:     ' return error.     errnumber = err.number     errormox "tilslutning af database"     ' resume able restore qdp.connect strconnectold.     resume next  end function

this way check complete route way single table.


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