GeezerVison

BFWQuery

(c) 2010-2014 BareFeetWare
Tom Brodhurst-Hill
[email protected]

Objectives:

1. Makes the power of SQLite available to Cocoa developers as simple as accessing arrays. Initialise a query, then get its resultArray.

2. Internally manages the array without storing all rows in RAM. BFWQuery creates the objects within a row lazily, when requested. So, whether your query resultArray is 10 rows or 10,000 rows, it shouldn’t take noticeably more memory.

Usage:

1. Instantiate a database connection, eg:

@property (nonatomic, strong) BFWDatabase* database;

- (BFWDatabase*)database
{
    if (!_database) {
        _database = [[BFWDatabase alloc] initWithPath:databasePath];
        [_database open];
    }
    return _database;
}

2. Create a query, eg:

BFWQuery* query = [[BFWQuery alloc] initWithDatabase:self.database
                                         queryString:@"select * from Country order by Name where Name = ?"
                                           arguments:@[countryName]];

3. Access rows of the result array:

To get the number of rows in the result array: [query.resultArray count]

To get row 4, value in column "Name": query.resultArray[4][@"Name"]


4. Using BFWQuery in a UITableViewController:

See the BFWQuery sample project for more.

@interface BFWMasterViewController ()

@property (nonatomic, strong) BFWQuery* query;

@end

@implementation BFWMasterViewController

#pragma mark - accessors

- (BFWQuery*)query
{
    if (!_query) {
        _query = [[BFWQuery alloc] initWithDatabase:self.database
                                        queryString:@"select * from Country order by Name"
                                          arguments:nil];
    }
    return _query;
}

#pragma mark - Table View

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return [self.query.resultArray count];
}

- (UITableViewCell*)tableView:(UITableView*)tableView cellForRowAtIndexPath:(NSIndexPath*)indexPath
{
    UITableViewCell* cell = [tableView dequeueReusableCellWithIdentifier:@"Cell" forIndexPath:indexPath];

    cell.textLabel.text = self.query.resultArray[indexPath.row][@"Name"];
    cell.detailTextLabel.text = self.query.resultArray[indexPath.row][@"Code"];
    return cell;
}

Requirements:

1. In Xcode, add libsqlite to your project’s list of frameworks.

2. Add the BFWQuery.h and BFWQuery.m files to your project.

3. Add FMDB to your project, either the source files or the binary.

4. Works on iOS6 and later. It probably also works on iOS 5 and Mac OS X, but not tested.


License:

Use as you like, but keep the (c) BareFeetWare in the header and include “Includes BFWQuery class by BareFeetWare” in your app’s info panel or credits.

Many thanks to Gus Mueller for FMDB and Dr Richard Hipp for SQLite.