Executing Multiple queries

I was following a tutorial. it was working great..

my doubht is, to execute single query they executed in this method

"+ (void) getInitialDataToDisplay:(NSString *)dbPath {"  

as "select coffeeID, coffeeName from coffee""

that's fine. but for my next view if I want execute a new query like "select * from coffee where abc = 123".

where should I write this query? I have to create a new method and have to call 开发者_JS百科this new method or what? how can I execute another query?

1) If you're going to use sqlite. I suggest you learn how to add Core Data to your Application.

2) To answer your question. You could add a method to the coffee class to retrieve the data you need. It could be a class method implemented just like:

 + (void) getData:(NSString *)dbPath {
    SQLAppDelegate *appDelegate = (SQLAppDelegate *)[[UIApplication sharedApplication] delegate];

    if (sqlite3_open([dbPath UTF8String], &database) == SQLITE_OK) {

        // <---Modify the sqlite statement below
        const char *sql = "select coffeeID, coffeeName from coffee"; 
        sqlite3_stmt *selectstmt;
        if(sqlite3_prepare_v2(database, sql, -1, &selectstmt, NULL) == SQLITE_OK) {

            while(sqlite3_step(selectstmt) == SQLITE_ROW) {

                NSInteger primaryKey = sqlite3_column_int(selectstmt, 0);
                Coffee *coffeeObj = [[Coffee alloc] initWithPrimaryKey:primaryKey];
                coffeeObj.coffeeName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(selectstmt, 1)]; // <-- create objects in coffeeObj that you want to do something with.

                coffeeObj.isDirty = NO;

                [appDelegate.coffeeArray addObject:coffeeObj];
                [coffeeObj release];
            }
        }
    }
    else
        sqlite3_close(database); //Even though the open call failed, close the database connection to release all the memory.
}

Make sure you add the corresponding method to the .h file as well.