Question

I am trying to save more than 500 records at once in sqlite, code that I have wrote so far is given below

The method name closeDatabase closes any open connection of the database the variable ContactID is nothing but an Array which is populated with ContactID of people present in my address book.

 sqlite3_exec(databaseRefObj, "BEGIN TRANSACTION", 0, 0, 0);

                for (NSString *contactIDstr in contactID)
                {
                    const char *insertintoGropsMember = "My insert query here";
                    NSString *groupIDstr = [NSString stringWithFormat:@"%d",grpID];

                    [self closeDatabase];

                    if(sqlite3_prepare_v2(databaseRefObj, insertintoGropsMember, -1, &sqlstatement, NULL)==SQLITE_OK)
                    {
                        sqlite3_bind_text(sqlstatement, 1, [groupIDstr UTF8String], -1, SQLITE_TRANSIENT);
                        sqlite3_bind_text(sqlstatement, 2, [contactIDstr UTF8String], -1, SQLITE_TRANSIENT);
                        sqlite3_step(sqlstatement);
                    }
                    else
                    {
                        successFlag = NO;
                    }


                    sqlite3_finalize(sqlstatement);
                    sqlite3_close(databaseRefObj);
                }

                sqlite3_exec(databaseRefObj, "END TRANSACTION", 0, 0, 0);

The process of data insertion is quite slow here and I would like to know where am I going wrong or what steps should I follow to optimize my sqlite performance.

Please note that I am not using any kind of index on the column on which I want to perform the insert.

Answer 1

I can see several issues with your code:

• You appear to be closing the database during processing.
• You aren’t taking advantage of the statement prepare/multiple binding capability.
• You are binding the integers as text, when sqlite3 will happily bind integer values

Try this code:

BOOL ok = YES;
sqlite3_exec(databaseRefObj, "BEGIN TRANSACTION", 0, 0, 0);
const char *insertintoGropsMember = "My insert query here";
if (sqlite3_prepare_v2(databaseRefObj, insertintoGropsMember, -1, &sqlstatement, NULL) == SQLITE_OK)
{
    for (NSString *contactIDstr in contactID)
    {
        sqlite3_bind_int(sqlstatement, 1, grpID);
        sqlite3_bind_text(sqlstatement, 2, [contactIDstr UTF8String], -1, 0);
        if (sqlite3_step(sqlstatement) != SQLITE_DONE)
        {
            NSLog(@"Error inserting row: %s", sqlite3_errmsg(databaseRefObj));
            ok = NO;
            break;
        }
        sqlite3_reset(sqlstatement);
    }
    sqlite3_finalize(sqlstatement);

    sqlite3_exec(databaseRefObj, ok ? "COMMIT" : "ROLLBACK", 0, 0, 0);
}
else
{
    NSLog(@"Error preparing statement: %s", sqlite3_errmsg(databaseRefObj));
}