Redirecting clients with application code

The following example shows an example of a function in a client application using the DBPATH redirection mechanism that loops as it attempts to reconnect. After it establishes a connection, it also tests the type of the database server to make sure it is not a secondary database server. If the database server is still a secondary type, it calls another function to alert the user (or database server administrator) that the database server cannot accept updates.

/* The routine assumes that the ONEDB_SERVER environment
 * variable is set to the database server that the client 
 * normally uses and that the DBPATH environment variable 
 * is set to the other database server in the pair.
 */

#define SLEEPTIME 15
#define MAXTRIES 10

main()
{
   int connected = 0;
   int tries;
   for (tries = 0;tries < MAXTRIES && connected == 0;tries++)
   {
      EXEC SQL CONNECT TO "superstores";
      if (strcmp(SQLSTATE,"00000"))
      {
         if (sqlca.sqlwarn.sqlwarn6 != 'W')
         {
            notify_admin();
            if (tries < MAXTRIES - 1)
               sleep(SLEEPTIME);
            }
         else connected =1;
         }
      }
   return ((tries == MAXTRIES)? -1:0);
   }

This example assumes the DBPATH redirection mechanism and uses a form of the CONNECT statement that supports the DBPATH redirection method. If you used the connectivity information to redirect, you might have a different connection statement, as follows:

EXEC SQL CONNECT TO "superstores@cliff_ol";