SQL Functionality in OOP C++ (Part 3/4 )

Delete Record –

To delete the record or rows or columns in SQL , we can use directly the query but as we are using same functionality in cpp .We need to first create record and then by including SQL libraries in code blocks following with delete record code ,delete function is implemented in our project.

Code-

cout<<"\nDelete Operation\n";

query = "DELETE FROM STUDENT WHERE ID = 2;";

exit = sqlite3_exec(DB, query.c_str(), callback, 0, &messaggeError);

if (exit != SQLITE_OK) {

std::cerr << "Error DELETE" << std::endl;

sqlite3_free(messaggeError);

}

else

std::cout << "Record deleted Successfully!" << std::endl;

Output-

Search –

Using this function of SQL ,we can search any element or elements from the given record and can display it. This is done similarly, in code blocks using SQLite library. Following code will explain the functionality .

Code-

cout<<"\nSearch Operation\n";

string data("CALLBACK FUNCTION");

/* Create merged SQL statement */

query = "SELECT * FROM STUDENT WHERE ID = 20;";

/* Execute SQL statement */

int rc = sqlite3_exec(DB, query.c_str(), callback, (void*)data.c_str(), NULL);

if (rc != SQLITE_OK)

cerr << "Error SELECT" << endl;

else {

cout << "Operation OK!" << endl;   }

Output-

Modify Record-

As name suggest, modify means to make changes and get it replaced in same record is the functionality of this SQL query. This is done by including terms to be modified in code using codeblocks.

Code-

cout<<"\nModify Record\n";

/* Create merged SQL statement */   

query = "UPDATE STUDENT set CGPA = 0 where ID=20;

 "   "SELECT * from STUDENT";

   /* Execute SQL statement */

  rc = sqlite3_exec(DB, query.c_str(), callback, (void*)data.c_str(), NULL);   

 if( rc != SQLITE_OK )

{   

   fprintf(stderr, "SQL error: %s\n", messaggeError);       sqlite3_free(messaggeError);

   }

else

{   

   fprintf(stdout, "Operation done successfully\n");         }

Output-

Diksha Avhad
K3