FMDB 多線程

        如今ios裏使用的數據庫通常都是Sqlite，可是使用Sqlite有個不太好的地方就是在多線程的時候，會出現問題，sqlite只能打開一個讀或者寫連結。這樣的話多線程就會碰到資源佔用的問題。

我使用多線程的簡單例子：

SqliteManager.h 文件：

#import <Foundation/Foundation.h>

@interface SqliteManager : NSObject

+(instancetype)shareSqliteManager;

- (BOOL)insertUserInfo;

SqliteManager.m文件

#import "SqliteManager.h"
#import "FMDB.h"


@interface SqliteManager ()

@property(nonatomic , strong)FMDatabaseQueue *fmdbQueue;

@end

@implementation SqliteManager

+ (instancetype)shareSqliteManager{
    
    static SqliteManager *manager = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        manager = [[SqliteManager alloc] init];
    });
    return manager;
}

- (instancetype)init{
    if (self = [super init]) {
        NSString *document = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0];
        NSString *filePath = [document stringByAppendingPathComponent:@"Umine.sqlite"];
        _fmdbQueue = [FMDatabaseQueue databaseQueueWithPath:filePath];
        
        [_fmdbQueue inDatabase:^(FMDatabase *db) {
            [db open];
            //建立好友表
            BOOL result=[db executeUpdate:@"CREATE TABLE IF NOT EXISTS userInfo (mobile text , username text ,nickname text, gender text , e_username text PRIMARY KEY,remark_info text, head_pic_url text);"];
            if (result) {
                DLog(@"創用戶表成功");
            }else{
                DLog(@"創用戶表失敗");
            }
            [db close];
        }];
        DLog(@"%@",filePath);
    }
    return self;
}

#pragma mark --- 好友信息操做 ---

- (BOOL)insertUserInfo{
    NSString *sql = [NSString stringWithFormat:@"insert into %@ (mobile,username,nickname,remark_info,gender,e_username,head_pic_url) values (?,?,?,?,?,?,?)",tableName];
    __block BOOL result = NO;
    [_fmdbQueue inDatabase:^(FMDatabase *db) {
        [db open];
        result = [db executeUpdate:sql,model.mobile,model.username,model.nickname,model.remark_info, model.gender,model.e_username,model.head_pic_url];
        [db close];
    }];
    
    return result;
}