IOS数据库操作FMDB简单入门实例及文章讲解

#import <Foundation/Foundation.h> #import "sqlite3.h" #import "FMResultSet.h" #import "FMDatabasePool.h" #if ! __has_feature(objc_arc) #define FMDBAutorelease(__v) ([__v autorelease]); #define FMDBReturnAutoreleased FMDBAutorelease #define FMDBRetain(__v) ([__v retain]); #define FMDBReturnRetained FMDBRetain #define FMDBRelease(__v) ([__v release]); #define FMDBDispatchQueueRelease(__v) (dispatch_release(__v)); #else // -fobjc-arc #define FMDBAutorelease(__v) #define FMDBReturnAutoreleased(__v) (__v) #define FMDBRetain(__v) #define FMDBReturnRetained(__v) (__v) #define FMDBRelease(__v) // If OS_OBJECT_USE_OBJC=1, then the dispatch objects will be treated like ObjC objects // and will participate in ARC. // See the section on "Dispatch Queues and Automatic Reference Counting" in "Grand Central Dispatch (GCD) Reference" for details. #if OS_OBJECT_USE_OBJC #define FMDBDispatchQueueRelease(__v) #else #define FMDBDispatchQueueRelease(__v) (dispatch_release(__v)); #endif #endif #if !__has_feature(objc_instancetype) #define instancetype id #endif typedef int(^FMDBExecuteStatementsCallbackBlock)(NSDictionary *resultsDictionary); /** A SQLite ([http://sqlite.org/](http://sqlite.org/)) Objective-C wrapper. ### Usage The three main classes in FMDB are: - `FMDatabase` - Represents a single SQLite database. Used for executing SQL statements. - `<FMResultSet>` - Represents the results of executing a query on an `FMDatabase`. - `<FMDatabaseQueue>` - If you want to perform queries and updates on multiple threads, you'll want to use this class. ### See also - `<FMDatabasePool>` - A pool of `FMDatabase` objects. - `<FMStatement>` - A wrapper for `sqlite_stmt`. ### External links - [FMDB on GitHub](https://github.com/ccgus/fmdb) including introductory documentation - [SQLite web site](http://sqlite.org/) - [FMDB mailing list](http://groups.google.com/group/fmdb) - [SQLite FAQ](http://www.sqlite.org/faq.html) @warning Do not instantiate a single `FMDatabase` object and use it across multiple threads. Instead, use `<FMDatabaseQueue>`. */ #pragma clang diagnostic push #pragma clang diagnostic ignored "-Wobjc-interface-ivars" @interface FMDatabase : NSObject { sqlite3* _db; NSString* _databasePath; BOOL _logsErrors; BOOL _crashOnErrors; BOOL _traceExecution; BOOL _checkedOut; BOOL _shouldCacheStatements; BOOL _isExecutingStatement; BOOL _inTransaction; NSTimeInterval _maxBusyRetryTimeInterval; NSTimeInterval _startBusyRetryTime; NSMutableDictionary *_cachedStatements; NSMutableSet *_openResultSets; NSMutableSet *_openFunctions; NSDateFormatter *_dateFormat; } ///----------------- /// @name Properties ///----------------- /** Whether should trace execution */ @property (atomic, assign) BOOL traceExecution; /** Whether checked out or not */ @property (atomic, assign) BOOL checkedOut; /** Crash on errors */ @property (atomic, assign) BOOL crashOnErrors; /** Logs errors */ @property (atomic, assign) BOOL logsErrors; /** Dictionary of cached statements */ @property (atomic, retain) NSMutableDictionary *cachedStatements; ///--------------------- /// @name Initialization ///--------------------- /** Create a `FMDatabase` object. An `FMDatabase` is created with a path to a SQLite database file. This path can be one of these three: 1. A file system path. The file does not have to exist on disk. If it does not exist, it is created for you. 2. An empty string (`@""`). An empty database is created at a temporary location. This database is deleted with the `FMDatabase` connection is closed. 3. `nil`. An in-memory database is created. This database will be destroyed with the `FMDatabase` connection is closed. For example, to create/open a database in your Mac OS X `tmp` folder: FMDatabase *db = [FMDatabase databaseWithPath:@"/tmp/tmp.db"]; Or, in iOS, you might open a database in the app's `Documents` directory: NSString *docsPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0]; NSString *dbPath = [docsPath stringByAppendingPathComponent:@"test.db"]; FMDatabase *db = [FMDatabase databaseWithPath:dbPath]; (For more information on temporary and in-memory databases, read the sqlite documentation on the subject: [http://www.sqlite.org/inmemorydb.html](http://www.sqlite.org/inmemorydb.html)) @param inPath Path of database file @return `FMDatabase` object if successful; `nil` if failure. */ + (instancetype)databaseWithPath:(NSString*)inPath; /** Initialize a `FMDatabase` object. An `FMDatabase` is created with a path to a SQLite database file. This path can be one of these three: 1. A file system path. The file does not have to exist on disk. If it does not exist, it is created for you. 2. An empty string (`@""`). An empty database is created at a temporary location. This database is deleted with the `FMDatabase` connection is closed. 3. `nil`. An in-memory database is created. This database will be destroyed with the `FMDatabase` connection is closed. For example, to create/open a database in your Mac OS X `tmp` folder: FMDatabase *db = [FMDatabase databaseWithPath:@"/tmp/tmp.db"]; Or, in iOS, you might open a database in the app's `Documents` directory: NSString *docsPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0]; NSString *dbPath = [docsPath stringByAppendingPathComponent:@"test.db"]; FMDatabase *db = [FMDatabase databaseWithPath:dbPath]; (For more information on temporary and in-memory databases, read the sqlite documentation on the subject: [http://www.sqlite.org/inmemorydb.html](http://www.sqlite.org/inmemorydb.html)) @param inPath Path of database file @return `FMDatabase` object if successful; `nil` if failure. */ - (instancetype)initWithPath:(NSString*)inPath; ///----------------------------------- /// @name Opening and closing database ///----------------------------------- /** Opening a new database connection The database is opened for reading and writing, and is created if it does not already exist. @return `YES` if successful, `NO` on error. @see [sqlite3_open()](http://sqlite.org/c3ref/open.html) @see openWithFlags: @see close */ - (BOOL)open; /** Opening a new database connection with flags and an optional virtual file system (VFS) @param flags one of the following three values, optionally combined with the `SQLITE_OPEN_NOMUTEX`, `SQLITE_OPEN_FULLMUTEX`, `SQLITE_OPEN_SHAREDCACHE`, `SQLITE_OPEN_PRIVATECACHE`, and/or `SQLITE_OPEN_URI` flags: `SQLITE_OPEN_READONLY` The database is opened in read-only mode. If the database does not already exist, an error is returned. `SQLITE_OPEN_READWRITE` The database is opened for reading and writing if possible, or reading only if the file is write protected by the operating system. In either case the database must already exist, otherwise an error is returned. `SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE` The database is opened for reading and writing, and is created if it does not already exist. This is the behavior that is always used for `open` method. If vfs is given the value is passed to the vfs parameter of sqlite3_open_v2. @return `YES` if successful, `NO` on error. @see [sqlite3_open_v2()](http://sqlite.org/c3ref/open.html) @see open @see close */ #if SQLITE_VERSION_NUMBER >= 3005000 - (BOOL)openWithFlags:(int)flags; - (BOOL)openWithFlags:(int)flags vfs:(NSString *)vfsName; #endif /** Closing a database connection @return `YES` if success, `NO` on error. @see [sqlite3_close()](http://sqlite.org/c3ref/close.html) @see open @see openWithFlags: