This document summarizes and compares several iOS database options: NyaruDB, Realm, and FMDB. NyaruDB is a simple NoSQL key-value database written in Objective-C that can be used on iOS and OS X. Realm is a mobile database that provides an object-oriented interface and can replace SQLite and Core Data. FMDB is a wrapper for SQLite that aims to make SQLite database access in iOS easy. The document provides code examples for basic operations like queries, sorting and indexing with each database and benchmarks their performance for a test inserting 10,000 records.

1. NyaruDB

2. @starfruits_j (Little Gleam)

3. Azione
Azione
Web

4. Swift?!

5. Nator
© 2014 Azione Co.,Ltd. All Right Reserved.

6. DB ( )
SQL

7. DB

8. DB
typo
[NSString stringWithFormat:]
INDEX

9. SQLite(FMDB)
3GS

12. FMDatabaseQueue

13. REINDEX

14. ALTER TABLE mails ADD COLUMN answered INTEGER DEFAULT ....

16. ...

17. Sparrow
OpenSource

18. OSS !=
TokyoCabinet

20. NoSQL -
SQL
..

21. API ( )
NoJSON, NoARC NoIB

22. main.m
int main(int argc, char *argv[])
{
@autoreleasepool {
if ([AppSettings isOS8OrGreater]) {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([MB2AppDelegate class]));
}
return UIApplicationMain(argc, argv, nil, NSStringFromClass([ScreenFactory class]));
}
}

23. DB SQL
github

24. NyaruDB
https://github.com/kelp404/NyaruDB
( )SAN ( )
W
2013 4 7 1:05
MIT License
NyaruDB is a simple NoSQL database in
Objective-C. It could be run on iOS and OS X.
It is a key-valu pair NoSQL database. You could
search data by fields of the document.

25. DB
SQL

26. NyaruDB SQL

27. CocoaPods
SQL

28. _documentFilePath
_indexFilePath
NSFileHandle seek

30. Table key
select
(asyncFetch)
AsyncDisplayKit

31. 10

32. SQL
KeyValueStore
NSDictionary NSDictionary
- (NSString *)name {
return _dic[@"name"];
}
- (void)setName:(NSString *)name {
_dic[@"name"] = name;
}
JSON OK

33. NyaruCollection *col = [[NyaruDB instance] collection:@"articles"];
[col createIndex:@"user_id"];
[col put:@{
@"user_id" : @1
@"name" : @"Cocoa",
@"age" : @"test",
}];
instance singleton
collection close instance

34. JSON
- (instansetype)initWithDictionary:(NSDictionary *)dictionary {
if ((self = [super init])) {
_dic = dictionary;
}
return self;
}
- (void)save {
[self.col put:_dic];
}
"key" primarykey
key update

35. SELECT
NSArray *results = [[col all] fetch];

36. WHERE
NSDictionary *result = [[col where:@"user_id" equal:identifier] fetchFirst];

37. AND
where: => NyaruQuery
[[self.col where:@"user_id" less:100]
and:@"user_id" greater:10]];

38. NyaruQuery
- (NyaruQuery *)and:(NSString *)indexName equal:(id)value;
- (NyaruQuery *)and:(NSString *)indexName notEqual:(id)value;
- (NyaruQuery *)and:(NSString *)indexName less:(id)value;
- (NyaruQuery *)and:(NSString *)indexName lessEqual:(id)value;
- (NyaruQuery *)and:(NSString *)indexName greater:(id)value;
- (NyaruQuery *)and:(NSString *)indexName greaterEqual:(id)value;
- (NyaruQuery *)and:(NSString *)indexName like:(NSString *)value;
- (NyaruQuery *)or:(NSString *)indexName equal:(id)value;
- (NyaruQuery *)orderBy:(NSString *)indexName;
- (NyaruQuery *)orderByDESC:(NSString *)indexName;

40. : JSON
NSNull nil

41. limit length of field name is 255
limit of documents is 4,294,967,295
limit of document file size is 4G
key is unique and it is NSString
key only provides equal search
key is case sensitive
index is case insensitive
a field of the document should be same data type
which is index
sort query allow only one

42. http://realm.io/
Realm is a mobile database: a replacement for
SQLite & Core Data Realm can save you
thousands of lines of code & weeks of work, and
lets you craft amazing new user experiences.

43. CocoaPods
SQL
RLMObject
Table Class
@interface User : RLMObject
@property (nonatomic, copy) NSString *identifier;
@property (nonatomic, copy) NSString *name;
@end

47. SQL

48. @interface User : RLMObject
@property (nonatomic, copy) NSString *identifier;
@property (nonatomic, copy) NSString *name;
@end
+ (NSString *)primaryKey {
return @"identifier";
}

49. INSERT
[[RLMRealm defaultRealm] transactionWithBlock:^{
[[RLMRealm defaultRealm] addObject:user];
[[RLMRealm defaultRealm] addOrUpdateObject:user];
}];

50. SELECT
RLMResults *users = [User allObjects];

51. RLMResults
NSArray (for in )
@interface RLMResults : NSObject<RLMCollection, NSFastEnumeration>
...
- (id)objectAtIndex:(NSUInteger)index;
- (id)firstObject;
- (id)lastObject;
...
@end

52. WHERE
User *user = [[User objectsWhere:@"identifier = %@", identifier] firstObject];
NSPredicate NSPredicate

53. AND
objectsWhere: => RLMResults
[[User objectsWhere:@"age < %@", @(20)]
objectsWhere:@"age > %@", @(2)]];

54. RLMResults
@interface Picture : RLMObject
@property (nonatomic, assign) BOOL isDeleted;
...
+ (RLMResults *)pictures {
return [self objectsWhere:@"isDeleted = 0"];
}
+ (RLMResults *)deletedPictures {
return [self objectsWhere:@"isDeleted = 1"];
}
+ (RLMResults *)myPictures {
RLMResults *res = [self pictures];
res = [res objectsWhere:@"user_id", [Account identifier]];
res = [res sortedResultsUsingProperty:@"created" ascending:NO];
return res;
}

55. delete
[[RLMRealm defaultRealm] transactionWithBlock:^{
[[RLMRealm defaultRealm] deleteObjects:[Picture myPictures]];
}];

56. ...

57. Migration
[RLMRealm setSchemaVersion:9
withMigrationBlock:^(RLMMigration *migration, NSUInteger oldSchemaVersion) {
if (oldSchemaVersion < 8) {
[migration enumerateObjects:NSStringFromClass([Pictures class])
block:^(RLMObject *oldObject, RLMObject *newObject) {
newObject[@"updated"] = oldObject[@"created"];
}];
}
}];
schemaVersion

58. [RLMRealm defaultRealm]
DB
DB

59. notification
_token = [[RLMRealm defaultRealm]
addNotificationBlock:^(NSString *notification, RLMRealm *realm) {
// code
}];
NSMapTable token

60. AppDelegate migration
ViewController initWithCoder:
NSURL
Java
getter

61. https://github.com/jstarfruits/BenchDB
normal single main (10,000)
FMDB 00.24 49.194 00.617
NyaruDB 29.02 17.890 59.186
Realm 04.18 28.744 00.385

62. SQLite
Realm NyaruDB SQL
NyaruDB -
Realm -
FMDB -

63. Realm

64. Azione
azione.co.jp