Like a primary database, you can read records from your secondary
        database either by using the 
            
            
                DB->get()
                
                or
                DB->pget()
                
            methods, 
            
        or by using  
             
            a cursor on the secondary database. 
            
        The main difference between reading secondary and primary databases is that when
        you read a secondary database record, the secondary record's data is not
        returned to you. Instead, the primary key and data corresponding to the
        secondary key are returned to you.
    
For example, assuming your secondary database contains keys related to a person's full name:
#include <db.h> #include <string.h> ... DB *my_secondary_database; DBT key; /* Used for the search key */ DBT pkey, pdata; /* Used to return the primary key and data */ char *search_name = "John Doe"; /* Primary and secondary database opens omitted for brevity */ /* Zero out the DBTs before using them. */ memset(&key, 0, sizeof(DBT)); memset(&pkey, 0, sizeof(DBT)); memset(&pdata, 0, sizeof(DBT)); key.data = search_name; key.size = strlen(search_name) + 1; /* Returns the key from the secondary database, and the data from the * associated primary database entry. */ my_secondary_database->get(my_secondary_database, NULL, &key, &pdata, 0); /* Returns the key from the secondary database, and the key and data * from the associated primary database entry. */ my_secondary_database->pget(my_secondary_database, NULL, &key, &pkey, &pdata, 0);
        Note that, just like 
            
            a primary database,
            
        if your secondary database supports duplicate records then
             
            
                DB->get() 
                 
                and
                DB->pget() 
                 
            
        only return the first record found in a matching duplicates set. If you 
        want to see all the records related to a specific secondary key, then use a
            
            
                cursor opened on the secondary database. Cursors are described in 
                Using Cursors.