examples/dbapi/manDBAPIdelete.c

   1 // DBAPI Demo:  delete and read
   2
   3 #include<CSql.h>
   4 int main()
   5 {
   6         // Connect to the database
   7         Connection conn;
   8     DbRetVal rv = conn.open("root", "manager");
   9     if (rv != OK) return 1;
  10
  11         // get database manager
  12     DatabaseManager *dbMgr = conn.getDatabaseManager();
  13     if (dbMgr == NULL) { printf("Auth failed\n"); return 2;}
  14
  15         // open table
  16     Table *table = dbMgr->openTable("EMP");
  17     if (table == NULL)
  18     {
  19         printf("Unable to open table\n");
  20         dbMgr->dropTable("EMP");
  21         conn.close();
  22         return 3;
  23     }
  24
  25         // allocate fields to bind
  26     int id1 = 0;
  27         float sal=0.0;
  28         char name[20];
  29     int icount =0, i = 0;
  30
  31         // bind the allocated fields
  32     table->bindFld("empId", &id1);
  33     table->bindFld("name", name);
  34     table->bindFld("salary", &sal);
  35
  36     conn.startTransaction();
  37     table->setCondition(NULL);
  38     rv = table->execute();
  39     if (rv != OK)
  40     {
  41        dbMgr->closeTable(table);
  42        dbMgr->dropTable("EMP");
  43        conn.close();
  44        return 4;
  45     }
  46     printf("Scan before deletion\n");
  47     printf("********************\n");
  48     printf("EmpId | name\t| salary\n");
  49     printf("--------------------------\n");
  50
  51     void *fld2ptr, *tuple;
  52     while(true)
  53     {
  54         tuple = (char*)table->fetch() ;
  55         if (tuple == NULL) {break;}
  56         printf("%d  | %s\t| %6.2f\n", id1, name, sal);
  57     }
  58     conn.commit();
  59     rv=table->closeScan();
  60
  61     Condition p1;
  62     int val1 = 1005;
  63     p1.setTerm("empId",OpGreaterThan, &val1);
  64     table->setCondition(&p1);
  65     conn.startTransaction();
  66     rv=table->execute();
  67     if (rv != OK)
  68     {
  69        dbMgr->closeTable(table);
  70        dbMgr->dropTable("EMP");
  71        conn.close();
  72        return 5;
  73     }
  74
  75     while(true)
  76     {
  77         tuple = (char*)table->fetch() ;
  78         if (tuple == NULL) { break; }
  79         table->deleteTuple();
  80     }
  81     conn.commit();
  82     table->closeScan();
  83
  84     conn.startTransaction();
  85     table->setCondition(NULL);
  86     rv = table->execute();
  87     if (rv != OK)
  88     {
  89        dbMgr->closeTable(table);
  90        dbMgr->dropTable("EMP");
  91        conn.close();
  92        return 4;
  93     }
  94     printf("Scan after deletion\n");
  95     printf("********************\n");
  96     printf("EmpId | name\t| salary\n");
  97     printf("--------------------------\n");
  98
  99     while(true)
 100     {
 101         tuple = (char*)table->fetch() ;
 102         if (tuple == NULL) {break;}
 103         printf("%d  | %s\t| %6.2f\n", id1, name, sal);
 104     }
 105     conn.commit();
 106     rv=table->closeScan();
 107     dbMgr->closeTable(table);
 108         dbMgr->dropTable("EMP");
 109     conn.close();
 110     return 0;
 111 }