dstd/bldatabase

BLDatabase

1. This ORM data access
2. Database changes reflect to NSIndexPath that will refresh UI automatically
3. Read write concurrency
4. You could preload a few properties, when you access others properties than load from disk
5. LRU objects cache
6. Based on FMDB

Usage

There six main classes in BLDatabase

1. BLBaseDBObject Represents table and attributes
2. BLDatabase Represents database. Used for creating data connections
3. BLDatabaseConnection Used for creating transaction
4. BLDatabaseTransaction Used for insert, update, delete, find objects
5. BLFetchedResultsController Used for refreshing UI automatically
6. BLFetchRequest Represents sql

Create database model

Create a class extend from BLBaseDBObject

#import "BLBaseDBObject.h"

BL_ARRAY_TYPE(BLAccount);

@interface BLAccount : BLBaseDBObject

@property (nonatomic, copy) NSString *accessToken;
@property (nonatomic, copy) NSString *userId;
@property (nonatomic, copy) NSString *nickname;

@property (nonatomic, strong) BLAccount *relationship;  // one to one
@property (nonatomic, copy) NSString *relationshipId;   // name must be [relationshipname] + [Id]

@property (nonatomic, strong) NSArray<BLAccount> *relationships; // one to many
@property (nonatomic, copy) NSArray *relationshipsIds;           // name must be [relationshipname] + [Ids]

@end

Create table and migration

self.database = [BLDatabase defaultDatabase];
[self.database setSchemaVersion:1
             withMigrationBlock:^(BLDatabaseReadWriteTransaction *transaction, NSUInteger oldSchemaVersion) {
                  [BLTestObject createTableAndIndexIfNeededInTransaction:transaction];
                  [BLAccount createTableAndIndexIfNeededInTransaction:transaction];
             }];

Executing find

// async find
BLDatabaseConnection *connection = [self.database connection];
[connection asyncReadWriteTransaction:^(BLDatabaseReadWriteTransaction *readWriteTransaction, BOOL *rollback) {
    NSArray *result = [BLTestObject findObjectsInTransaction:readWriteTransaction
                                                 withRequest:nil];
}];

// sync find
BLDatabaseConnection *connection = [self.database connection];
[connection syncReadWriteTransaction:^(BLDatabaseReadWriteTransaction *readWriteTransaction, BOOL *rollback) {
    NSArray *result = [BLTestObject findObjectsInTransaction:readWriteTransaction
                                                 withRequest:nil];
}];

Executing insert update delete

// async transaction
BLDatabaseConnection *connection = [database connection];
[connection asyncReadWriteTransaction:^(BLDatabaseReadWriteTransaction *readWriteTransaction, BOOL *rollback) {
  //...
}];

// sync transaction
BLDatabaseConnection *connection = [database connection];
[connection syncReadWriteTransaction:^(BLDatabaseReadWriteTransaction *readWriteTransaction, BOOL *rollback) {
  //...
}];

BLDatabaseConnection *connection = [database connection];
[connection syncReadWriteTransaction:^(BLDatabaseReadWriteTransaction *readWriteTransaction, BOOL *rollback) {
      // insert
      BLTestObject *object = [BLTestObject new];
      object.age = 20;
      object.name = @"test";
      [readWriteTransaction insertObject:object];
      
      // update
      object.age = 30;
      [readWriteTransaction updateObject:object];
      
      // delete
      [readWriteTransaction deleteObject:object];
}];

Relationship

// one to one
BLDatabaseConnection *connection = [database connection];
[connection syncReadWriteTransaction:^(BLDatabaseReadWriteTransaction *readWriteTransaction, BOOL *rollback) {
    BLAccount *account = [BLAccount new];
    NSString *uniqueId = account.uniqueId;
    BLAccount *account1 = [BLAccount new];
    NSString *uniqueId1 = account1.uniqueId;
    account.relationship = account1;
    account1.relationship = account;
    [readWriteTransaction insertObjects:@[account, account1]];
}];

// one to many
BLDatabaseConnection *connection = [database connection];
[connection syncReadWriteTransaction:^(BLDatabaseReadWriteTransaction *readWriteTransaction, BOOL *rollback) {
    BLAccount *account = [BLAccount new];
    NSString *uniqueId = account.uniqueId;
    
    BLAccount *account1 = [BLAccount new];
    NSString *uniqueId1 = account1.uniqueId;
    
    BLAccount *account2 = [BLAccount new];
    NSString *uniqueId2 = account2.uniqueId;
    
    account.relationships = (NSArray<BLAccount> *)@[account1, account2];
    [readWriteTransaction insertObjects:@[account, account1, account2]];
}];

BLFetchedResultsController

// create 
BLFetchRequest *request = [BLFetchRequest new];
request.sqlAfterWhere = nil;
request.fieldNames = @[@"name", @"groupName"];
request.sortTerm = @"name:1";
BLDatabaseConnection *connection = [database connection];

BLFetchedResultsController *controller = [[BLFetchedResultsController alloc] initWithFetchRequest:request
                                                                                   groupByKeyPath:@"groupName"
                                                                                   groupAscending:YES
                                                                                      objectClass:[BLTestObject class]
                                                                                     inConnection:connection];
controller.delegate = self;
[controller performFetch];
[self.tableView reloadData];

// refresh ui
- (void)controller:(BLFetchedResultsController *)controller didChangeWithIndexSet:(NSIndexSet *)indexSet forChangeType:(BLFetchedResultsChangeType)type
{
    if (type == BLFetchedResultsChangeInsert) {
        [self.tableView insertSections:indexSet withRowAnimation:UITableViewRowAnimationAutomatic];
    } else if (type == BLFetchedResultsChangeDelete) {
        [self.tableView deleteSections:indexSet withRowAnimation:UITableViewRowAnimationAutomatic];
    }
}

- (void)controller:(BLFetchedResultsController *)controller didChangeWithIndexPaths:(NSArray *)indexPaths forChangeType:(BLFetchedResultsChangeType)type
{
    if (type == BLFetchedResultsChangeInsert) {
        [self.tableView insertRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationLeft];
    } else if (type == BLFetchedResultsChangeUpdate) {
        [self.tableView reloadRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationFade];
    } else if (type == BLFetchedResultsChangeDelete) {
        [self.tableView deleteRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationRight];
    }
}

- (void)controllerWillChangeContent:(BLFetchedResultsController *)controller
{
    [self.tableView beginUpdates];
}

- (void)controllerDidChangeContent:(BLFetchedResultsController *)controller
{
    [self.tableView endUpdates];
}