examples/dbapi/dbapiexample.c

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by www.databasecache.com                           *
   3  *   Contact: praba_tuty@databasecache.com                                 *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15   **************************************************************************/
  16 #include<CSql.h>
  17 int main()
  18 {
  19     //connect to the database first
  20     Connection conn;
  21     DbRetVal rv = conn.open("root", "manager");
  22     if (rv != OK)
  23     {
  24        printf("Error during connection %d\n", rv);
  25        return -1;
  26     }
  27
  28     //get dbmgr to create table and index
  29     DatabaseManager *dbMgr = conn.getDatabaseManager();
  30     if (dbMgr == NULL) { printf("Auth failed\n"); return -1;}
  31
  32     //create table with two fields, f1 integer and f2 string
  33     TableDef tabDef;
  34     tabDef.addField("f1", typeInt, 0, NULL, true);
  35     tabDef.addField("f2", typeString, 20);
  36     rv = dbMgr->createTable("t1", tabDef);
  37     if (rv != OK) { printf("Table creation failed\n"); return -1; }
  38     printf("Table created\n");
  39
  40     //Creating hash index on field f1 of table t1
  41     HashIndexInitInfo *idxInfo = new HashIndexInitInfo();
  42     strcpy(idxInfo->tableName, "t1");
  43     idxInfo->list.append("f1");
  44     idxInfo->indType = hashIndex;
  45     rv = dbMgr->createIndex("indx1", idxInfo);
  46     if (rv != OK) { printf("Index creation failed\n"); return -1; }
  47     printf("Index created\n");
  48
  49     //open the table handle for doing DML operations
  50     Table *table = dbMgr->openTable("t1");
  51     if (table == NULL) { printf("Unable to open table\n"); return -1; }
  52     int id = 0;
  53     char name[20] = "THIRU";
  54     table->bindFld("f1", &id);
  55     table->bindFld("f2", name);
  56     char *tuple;
  57     int ret;
  58     int i;
  59     int icount =0;
  60     char names[10][20]={"Ganga", "Gopal", "Chaitra", "Aruna", "Vinayak", "Shekar",
  61                         "Pramod", "Rakesh", "Murthy", "Amit" };
  62
  63     //insert 10 tuples into the table t1
  64     for(i = 0; i< 10; i++)
  65     {
  66         conn.startTransaction();
  67         id= i;
  68         strcpy(name, names[i]);
  69         ret = table->insertTuple();
  70         if (ret != 0) break;
  71         icount++;
  72         conn.commit();
  73     }
  74     char msgBuf[1024];
  75     sprintf(msgBuf,"Total rows inserted %d \n",icount);
  76     os::write(1,msgBuf,strlen(msgBuf));
  77
  78     //set the condition f1 >=5
  79     Condition p1;
  80     int val1 = 5;
  81     p1.setTerm("f1", OpGreaterThanEquals, &val1);
  82     table->setCondition(&p1);
  83     icount=0;
  84     printf("Selection f1 >= 5 starts on table t1\n");
  85     conn.startTransaction();
  86     table->execute();
  87     printf("Tuple values:\n");
  88     while(true)
  89     {
  90         tuple = (char*)table->fetch() ;
  91         if (tuple == NULL) { break; }
  92         printf("    f1=%d f2=%s\n", id, name);
  93         icount++;
  94     }
  95     table->close();
  96     conn.commit();
  97     sprintf(msgBuf,"Total Rows selected: %d \n", icount);
  98     os::write(1,msgBuf,strlen(msgBuf));
  99
 100     //unset the condtion set as we need to delete all rows
 101     table->setCondition(NULL);
 102     conn.startTransaction();
 103     table->execute();
 104     icount = 0;
 105     while(true)
 106     {
 107         tuple = (char*)table->fetch();
 108         if (tuple == NULL)  { break;}
 109         table->deleteTuple();
 110         icount++;
 111     }
 112     conn.commit();
 113     table->close();
 114     printf("Total Deleted Rows %d\n", icount);
 115
 116     dbMgr->closeTable(table);
 117     dbMgr->dropTable("t1");
 118     printf("Table dropped\n");
 119     conn.close();
 120     return 0;
 121 }