iOS中使用FMDB对数据库的操作（二）

前一篇文章写了FMDB语法的基本语法，主要用于初步在学习阶段使用，要想正式使用的时候，我们肯定不能一句句的去写那些复杂的代码，最近有几个项目用到了FMDB，正好整理封装了一下，使用更方便。

采用单例模式，在想使用的类中加入 #import "YJFMDB.h" 。使用的时候直接调用，如：

保存：[[YJFMDB shareDatabase] YJ_saveTable:@"tableName" dicOrModel:dict];

所有方法在.h中有详细的注释，可根据自己具体的使用情况进行扩展、

另外一个需要注意的就是在程序第一次使用，或者本地不存在数据库的时候进行创建表的操作。这个需要提前知道表结构，代码如下：

if (![[JQFMDB shareDatabase]YJ_isExistTable:@"TableName"]) {//无表则建表

        BOOL success = [[JQFMDB shareDatabase]YJ_createTable:@"TableName" dicOrModel:@{@"type_name":@"TEXT",@"type_icon_name":@"TEXT",@"kind":@"TEXT"}];

        NSLog(@"---建表%@",success?@"成功！":@"失败！");

    }

下面贴上具体的.h中的方法介绍：

YJFMDB.h

#import 



@interface YJFMDB : NSObject



/**

 (主键id,自动创建) 返回最后插入的primary key id

 @param tableName 表的名称

 */

- (NSInteger)lastInsertPrimaryKeyId:(NSString *)tableName;



/**

 单例方法创建数据库, 如果使用shareDatabase创建,则默认在NSDocumentDirectory下创建JQFMDB.sqlite, 但只要使用这三个方法任意一个创建成功, 之后即可使用三个中任意一个方法获得同一个实例,参数可随意或nil

 

 dbName 数据库的名称 如: @"Users.sqlite", 如果dbName = nil,则默认dbName=@"JQFMDB.sqlite"

 dbPath 数据库的路径, 如果dbPath = nil, 则路径默认为NSDocumentDirectory

 */

+ (instancetype)shareDatabase;

+ (instancetype)shareDatabase:(NSString *)dbName;

+ (instancetype)shareDatabase:(NSString *)dbName path:(NSString *)dbPath;



/**

 非单例方法创建数据库

 

 @param dbName 数据库的名称 如: @"Users.sqlite"

 dbPath 数据库的路径, 如果dbPath = nil, 则路径默认为NSDocumentDirectory

 */

- (instancetype)initWithDBName:(NSString *)dbName;

- (instancetype)initWithDBName:(NSString *)dbName path:(NSString *)dbPath;



/**

 创建表 通过传入的model或dictionary(如果是字典注意类型要写对),虽然都可以不过还是推荐以下都用model

 

 @param tableName 表的名称

 @param parameters 设置表的字段,可以传model(runtime自动生成字段)或字典(格式:@{@"name":@"TEXT"})

 @return 是否创建成功

 */

- (BOOL)YJ_createTable:(NSString *)tableName dicOrModel:(id)parameters;



/**

 同上,

 @param nameArr 不允许model或dic里的属性/key生成表的字段,如:nameArr = @[@"name"],则不允许名为name的属性/key 生成表的字段

 

 */

- (BOOL)YJ_createTable:(NSString *)tableName dicOrModel:(id)parameters excludeName:(NSArray *)nameArr;



/**

 增加: 向表中插入数据

 

 @param tableName 表的名称

 @param parameters 要插入的数据,可以是model或dictionary(格式:@{@"name":@"小李"})

 @return 是否插入成功

 */

- (BOOL)YJ_saveTable:(NSString *)tableName dicOrModel:(id)parameters;



/**

 删除: 根据条件删除表中数据

 

 @param tableName 表的名称

 @param format 条件语句, 如:@"where name = '小李'"

 @return 是否删除成功

 */

- (BOOL)YJ_deleteTable:(NSString *)tableName whereFormat:(NSString *)format, ...;



/**

 更改: 根据条件更改表中数据

 

 @param tableName 表的名称

 @param parameters 要更改的数据,可以是model或dictionary(格式:@{@"name":@"张三"})

 @param format 条件语句, 如:@"where name = '小李'"

 @return 是否更改成功

 */

- (BOOL)YJ_updateTable:(NSString *)tableName dicOrModel:(id)parameters whereFormat:(NSString *)format, ...;



/**

 查找: 根据条件查找表中数据

 

 @param tableName 表的名称

 @param parameters 每条查找结果放入model(可以是[Person class] or @"Person" or Person实例)或dictionary中

 @param format 条件语句, 如:@"where name = '小李'",

 @return 将结果存入array,数组中的元素的类型为parameters的类型

 */

- (NSArray *)YJ_findTable:(NSString *)tableName dicOrModel:(id)parameters whereFormat:(NSString *)format, ...;



/**

 批量插入或更改

 

 @param dicOrModelArray 要insert/update数据的数组,也可以将model和dictionary混合装入array

 @return 返回的数组存储未插入成功的下标,数组中元素类型为NSNumber

 */

- (NSArray *)YJ_saveTable:(NSString *)tableName dicOrModelArray:(NSArray *)dicOrModelArray;



// `删除表

- (BOOL)YJ_deleteTable:(NSString *)tableName;

// `清空表

- (BOOL)YJ_deleteAllDataFromTable:(NSString *)tableName;

// `是否存在表

- (BOOL)YJ_isExistTable:(NSString *)tableName;

// `表中共有多少条数据

- (int)YJ_tableItemCount:(NSString *)tableName;

// `返回表中的字段名

- (NSArray *)YJ_columnNameArray:(NSString *)tableName;



// `关闭数据库

- (void)close;

// `打开数据库 (每次shareDatabase系列操作时已经open,当调用close后若进行db操作需重新open或调用shareDatabase)

- (void)open;



/**

 增加新字段, 在建表后还想新增字段,可以在原建表model或新model中新增对应属性,然后传入即可新增该字段,该操作已在事务中执行

 

 @param tableName 表的名称

 @param parameters 如果传Model:数据库新增字段为建表时model所没有的属性,如果传dictionary格式为@{@"newname":@"TEXT"}

 @param nameArr 不允许生成字段的属性名的数组

 @return 是否成功

 */

- (BOOL)YJ_alterTable:(NSString *)tableName dicOrModel:(id)parameters excludeName:(NSArray *)nameArr;

- (BOOL)YJ_alterTable:(NSString *)tableName dicOrModel:(id)parameters;





// =============================   线程安全操作    ===============================



/**

 将操作语句放入block中即可保证线程安全, 如:

 

 Person *p = [[Person alloc] init];

 p.name = @"小李";

 [jqdb jq_inDatabase:^{

 [jqdb jq_insertTable:@"users" dicOrModel:p];

 }];

 */

- (void)YJ_inDatabase:(void (^)(void))block;





/**

 事务: 将操作语句放入block中可执行回滚操作(*rollback = YES;)

 

 Person *p = [[Person alloc] init];

 p.name = @"小李";

 

 for (int i=0,i < 1000,i++) {

 [jq jq_inTransaction:^(BOOL *rollback) {

 BOOL flag = [jq jq_insertTable:@"users" dicOrModel:p];

 if (!flag) {

 *rollback = YES; //只要有一次不成功,则进行回滚操作

 return;

 }

 }];

 }

 

 */

- (void)YJ_inTransaction:(void(^)(BOOL *rollback))block;





@end

YJFMDB.m

#import "YJFMDB.h"
#import "FMDB.h"
#import 


// 数据库中常见的几种类型
#define SQL_TEXT     @"TEXT" //文本
#define SQL_INTEGER  @"INTEGER" //int long integer ...
#define SQL_REAL     @"REAL" //浮点
#define SQL_BLOB     @"BLOB" //data

@interface YJFMDB()

@property (nonatomic, strong)NSString *dbPath;
@property (nonatomic, strong)FMDatabaseQueue *dbQueue;
@property (nonatomic, strong)FMDatabase *db;

@end


@implementation YJFMDB

- (FMDatabaseQueue *)dbQueue
{
    if (!_dbQueue) {
        FMDatabaseQueue *fmdb = [FMDatabaseQueue databaseQueueWithPath:_dbPath];
        self.dbQueue = fmdb;
        [_db close];
        self.db = [fmdb valueForKey:@"_db"];
    }
    return _dbQueue;
}
static YJFMDB *jqdb = nil;
+ (instancetype)shareDatabase
{
    return [YJFMDB shareDatabase:nil];
}

+ (instancetype)shareDatabase:(NSString *)dbName
{
    return [YJFMDB shareDatabase:dbName path:nil];
}
+ (instancetype)shareDatabase:(NSString *)dbName path:(NSString *)dbPath
{
    if (!jqdb) {
        
        NSString *path;
        if (!dbName) {
            dbName = @"JQFMDB.sqlite";
        }
        if (!dbPath) {
            path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingPathComponent:dbName];
        } else {
            path = [dbPath stringByAppendingPathComponent:dbName];
        }
        
        FMDatabase *fmdb = [FMDatabase databaseWithPath:path];
        if ([fmdb open]) {
            jqdb = YJFMDB.new;
            jqdb.db = fmdb;
            jqdb.dbPath = path;
        }
    }
    if (![jqdb.db open]) {
        NSLog(@"database can not open !");
        return nil;
    };
    return jqdb;
}

- (instancetype)initWithDBName:(NSString *)dbName
{
    return [self initWithDBName:dbName path:nil];
}

- (instancetype)initWithDBName:(NSString *)dbName path:(NSString *)dbPath
{
    if (!dbName) {
        dbName = @"YJFMDB.sqlite";
    }
    NSString *path;
    if (!dbPath) {
        path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingPathComponent:dbName];
    } else {
        path = [dbPath stringByAppendingPathComponent:dbName];
    }
    
    FMDatabase *fmdb = [FMDatabase databaseWithPath:path];
    
    if ([fmdb open]) {
        self = [self init];
        if (self) {
            self.db = fmdb;
            self.dbPath = path;
            return self;
        }
    }
    return nil;
}

-(BOOL)YJ_createTable:(NSString *)tableName dicOrModel:(id)parameters{
    return [self YJ_createTable:tableName dicOrModel:parameters excludeName:nil];
}

-(BOOL)YJ_createTable:(NSString *)tableName dicOrModel:(id)parameters excludeName:(NSArray *)nameArr{
    NSDictionary *dic;
    if ([parameters isKindOfClass:[NSDictionary class]]) {
        dic = parameters;
    } else {
        Class CLS;
        if ([parameters isKindOfClass:[NSString class]]) {
            if (!NSClassFromString(parameters)) {
                CLS = nil;
            } else {
                CLS = NSClassFromString(parameters);
            }
        } else if ([parameters isKindOfClass:[NSObject class]]) {
            CLS = [parameters class];
        } else {
            CLS = parameters;
        }
        dic = [self modelToDictionary:CLS excludePropertyName:nameArr];
    }
    
    NSMutableString *fieldStr = [[NSMutableString alloc] initWithFormat:@"CREATE TABLE %@ (pkid  INTEGER PRIMARY KEY,", tableName];
    
    int keyCount = 0;
    for (NSString *key in dic) {
        
        keyCount++;
        if ((nameArr && [nameArr containsObject:key]) || [key isEqualToString:@"pkid"]) {
            continue;
        }
        if (keyCount == dic.count) {
            [fieldStr appendFormat:@" %@ %@)", key, dic[key]];
            break;
        }
        
        [fieldStr appendFormat:@" %@ %@,", key, dic[key]];
    }
    
    BOOL creatFlag;
    creatFlag = [_db executeUpdate:fieldStr];
    
    return creatFlag;
}
- (NSString *)createTable:(NSString *)tableName dictionary:(NSDictionary *)dic excludeName:(NSArray *)nameArr
{
    NSMutableString *fieldStr = [[NSMutableString alloc] initWithFormat:@"CREATE TABLE %@ (pkid  INTEGER PRIMARY KEY,", tableName];
    
    int keyCount = 0;
    for (NSString *key in dic) {
        
        keyCount++;
        if ((nameArr && [nameArr containsObject:key]) || [key isEqualToString:@"pkid"]) {
            continue;
        }
        if (keyCount == dic.count) {
            [fieldStr appendFormat:@" %@ %@)", key, dic[key]];
            break;
        }
        
        [fieldStr appendFormat:@" %@ %@,", key, dic[key]];
    }
    
    return fieldStr;
}
- (NSString *)createTable:(NSString *)tableName model:(Class)cls excludeName:(NSArray *)nameArr
{
    NSMutableString *fieldStr = [[NSMutableString alloc] initWithFormat:@"CREATE TABLE %@ (pkid INTEGER PRIMARY KEY,", tableName];
    
    NSDictionary *dic = [self modelToDictionary:cls excludePropertyName:nameArr];
    int keyCount = 0;
    for (NSString *key in dic) {
        
        keyCount++;
        
        if ([key isEqualToString:@"pkid"]) {
            continue;
        }
        if (keyCount == dic.count) {
            [fieldStr appendFormat:@" %@ %@)", key, dic[key]];
            break;
        }
        
        [fieldStr appendFormat:@" %@ %@,", key, dic[key]];
    }
    
    return fieldStr;
}
#pragma mark - *************** runtime
- (NSDictionary *)modelToDictionary:(Class)cls excludePropertyName:(NSArray *)nameArr
{
    NSMutableDictionary *mDic = [NSMutableDictionary dictionaryWithCapacity:0];
    unsigned int outCount;
    objc_property_t *properties = class_copyPropertyList(cls, &outCount);
    for (int i = 0; i < outCount; i++) {
        
        NSString *name = [NSString stringWithCString:property_getName(properties[i]) encoding:NSUTF8StringEncoding];
        if ([nameArr containsObject:name]) continue;
        
        NSString *type = [NSString stringWithCString:property_getAttributes(properties[i]) encoding:NSUTF8StringEncoding];
        
        id value = [self propertTypeConvert:type];
        if (value) {
            [mDic setObject:value forKey:name];
        }
        
    }
    free(properties);
    
    return mDic;
}
// 获取model的key和value
- (NSDictionary *)getModelPropertyKeyValue:(id)model tableName:(NSString *)tableName clomnArr:(NSArray *)clomnArr
{
    NSMutableDictionary *mDic = [NSMutableDictionary dictionaryWithCapacity:0];
    unsigned int outCount;
    objc_property_t *properties = class_copyPropertyList([model class], &outCount);
    
    for (int i = 0; i < outCount; i++) {
        
        NSString *name = [NSString stringWithCString:property_getName(properties[i]) encoding:NSUTF8StringEncoding];
        if (![clomnArr containsObject:name]) {
            continue;
        }
        
        id value = [model valueForKey:name];
        if (value) {
            [mDic setObject:value forKey:name];
        }
    }
    free(properties);
    
    return mDic;
}

- (NSString *)propertTypeConvert:(NSString *)typeStr
{
    NSString *resultStr = nil;
    if ([typeStr hasPrefix:@"T@\"NSString\""]) {
        resultStr = SQL_TEXT;
    } else if ([typeStr hasPrefix:@"T@\"NSData\""]) {
        resultStr = SQL_BLOB;
    } else if ([typeStr hasPrefix:@"Ti"]||[typeStr hasPrefix:@"TI"]||[typeStr hasPrefix:@"Ts"]||[typeStr hasPrefix:@"TS"]||[typeStr hasPrefix:@"T@\"NSNumber\""]||[typeStr hasPrefix:@"TB"]||[typeStr hasPrefix:@"Tq"]||[typeStr hasPrefix:@"TQ"]) {
        resultStr = SQL_INTEGER;
    } else if ([typeStr hasPrefix:@"Tf"] || [typeStr hasPrefix:@"Td"]){
        resultStr= SQL_REAL;
    }
    
    return resultStr;
}

// 得到表里的字段名称
- (NSArray *)getColumnArr:(NSString *)tableName db:(FMDatabase *)db
{
    NSMutableArray *mArr = [NSMutableArray arrayWithCapacity:0];
    
    FMResultSet *resultSet = [db getTableSchema:tableName];
    
    while ([resultSet next]) {
        [mArr addObject:[resultSet stringForColumn:@"name"]];
    }
    
    return mArr;
}

#pragma mark - *************** 增删改查

-(BOOL)YJ_saveTable:(NSString *)tableName dicOrModel:(id)parameters{
    NSArray *columnArr = [self getColumnArr:tableName db:_db];
    return [self insertTable:tableName dicOrModel:parameters columnArr:columnArr];
}

- (BOOL)insertTable:(NSString *)tableName dicOrModel:(id)parameters columnArr:(NSArray *)columnArr
{
    BOOL flag;
    NSDictionary *dic;
    if ([parameters isKindOfClass:[NSDictionary class]]) {
        dic = parameters;
    }else {
        dic = [self getModelPropertyKeyValue:parameters tableName:tableName clomnArr:columnArr];
    }
    
    NSMutableString *finalStr = [[NSMutableString alloc] initWithFormat:@"INSERT INTO %@ (", tableName];
    NSMutableString *tempStr = [NSMutableString stringWithCapacity:0];
    NSMutableArray *argumentsArr = [NSMutableArray arrayWithCapacity:0];
    
    for (NSString *key in dic) {
        
        if (![columnArr containsObject:key] || [key isEqualToString:@"pkid"]) {
            continue;
        }
        [finalStr appendFormat:@"%@,", key];
        [tempStr appendString:@"?,"];
        
        [argumentsArr addObject:dic[key]];
    }
    
    [finalStr deleteCharactersInRange:NSMakeRange(finalStr.length-1, 1)];
    if (tempStr.length)
        [tempStr deleteCharactersInRange:NSMakeRange(tempStr.length-1, 1)];
    
    [finalStr appendFormat:@") values (%@)", tempStr];
    
    flag = [_db executeUpdate:finalStr withArgumentsInArray:argumentsArr];
    return flag;
}


-(BOOL)YJ_deleteTable:(NSString *)tableName whereFormat:(NSString *)format, ...{
    va_list args;
    va_start(args, format);
    NSString *where = format?[[NSString alloc] initWithFormat:format locale:[NSLocale currentLocale] arguments:args]:format;
    va_end(args);
    BOOL flag;
    NSMutableString *finalStr = [[NSMutableString alloc] initWithFormat:@"delete from %@  %@", tableName,where];
    flag = [_db executeUpdate:finalStr];
    
    return flag;
}

-(BOOL)YJ_updateTable:(NSString *)tableName dicOrModel:(id)parameters whereFormat:(NSString *)format, ...{
    va_list args;
    va_start(args, format);
    NSString *where = format?[[NSString alloc] initWithFormat:format locale:[NSLocale currentLocale] arguments:args]:format;
    va_end(args);
    BOOL flag;
    NSDictionary *dic;
    NSArray *clomnArr = [self getColumnArr:tableName db:_db];
    if ([parameters isKindOfClass:[NSDictionary class]]) {
        dic = parameters;
    }else {
        dic = [self getModelPropertyKeyValue:parameters tableName:tableName clomnArr:clomnArr];
    }
    
    NSMutableString *finalStr = [[NSMutableString alloc] initWithFormat:@"update %@ set ", tableName];
    NSMutableArray *argumentsArr = [NSMutableArray arrayWithCapacity:0];
    
    for (NSString *key in dic) {
        
        if (![clomnArr containsObject:key] || [key isEqualToString:@"pkid"]) {
            continue;
        }
        [finalStr appendFormat:@"%@ = %@,", key, @"?"];
        [argumentsArr addObject:dic[key]];
    }
    
    [finalStr deleteCharactersInRange:NSMakeRange(finalStr.length-1, 1)];
    if (where.length) [finalStr appendFormat:@" %@", where];
    
    
    flag =  [_db executeUpdate:finalStr withArgumentsInArray:argumentsArr];
    
    return flag;
}

-(NSArray *)YJ_findTable:(NSString *)tableName dicOrModel:(id)parameters whereFormat:(NSString *)format, ...{
    va_list args;
    va_start(args, format);
    NSString *where = format?[[NSString alloc] initWithFormat:format locale:[NSLocale currentLocale] arguments:args]:format;
    va_end(args);
    NSMutableArray *resultMArr = [NSMutableArray arrayWithCapacity:0];
    NSDictionary *dic;
    NSMutableString *finalStr = [[NSMutableString alloc] initWithFormat:@"select * from %@ %@", tableName, where?where:@""];
    NSArray *clomnArr = [self getColumnArr:tableName db:_db];
    
    FMResultSet *set = [_db executeQuery:finalStr];
    
    if ([parameters isKindOfClass:[NSDictionary class]]) {
        dic = parameters;
        
        while ([set next]) {
            
            NSMutableDictionary *resultDic = [NSMutableDictionary dictionaryWithCapacity:0];
            for (NSString *key in dic) {
                
                if ([dic[key] isEqualToString:SQL_TEXT]) {
                    id value = [set stringForColumn:key];
                    if (value)
                        [resultDic setObject:value forKey:key];
                } else if ([dic[key] isEqualToString:SQL_INTEGER]) {
                    [resultDic setObject:@([set longLongIntForColumn:key]) forKey:key];
                } else if ([dic[key] isEqualToString:SQL_REAL]) {
                    [resultDic setObject:[NSNumber numberWithDouble:[set doubleForColumn:key]] forKey:key];
                } else if ([dic[key] isEqualToString:SQL_BLOB]) {
                    id value = [set dataForColumn:key];
                    if (value)
                        [resultDic setObject:value forKey:key];
                }
                
            }
            
            if (resultDic) [resultMArr addObject:resultDic];
        }
        
    }else {
        
        Class CLS;
        if ([parameters isKindOfClass:[NSString class]]) {
            if (!NSClassFromString(parameters)) {
                CLS = nil;
            } else {
                CLS = NSClassFromString(parameters);
            }
        } else if ([parameters isKindOfClass:[NSObject class]]) {
            CLS = [parameters class];
        } else {
            CLS = parameters;
        }
        
        if (CLS) {
            NSDictionary *propertyType = [self modelToDictionary:CLS excludePropertyName:nil];
            
            while ([set next]) {
                
                id model = CLS.new;
                for (NSString *name in clomnArr) {
                    if ([propertyType[name] isEqualToString:SQL_TEXT]) {
                        id value = [set stringForColumn:name];
                        if (value)
                            [model setValue:value forKey:name];
                    } else if ([propertyType[name] isEqualToString:SQL_INTEGER]) {
                        [model setValue:@([set longLongIntForColumn:name]) forKey:name];
                    } else if ([propertyType[name] isEqualToString:SQL_REAL]) {
                        [model setValue:[NSNumber numberWithDouble:[set doubleForColumn:name]] forKey:name];
                    } else if ([propertyType[name] isEqualToString:SQL_BLOB]) {
                        id value = [set dataForColumn:name];
                        if (value)
                            [model setValue:value forKey:name];
                    }
                }
                
                [resultMArr addObject:model];
            }
        }
        
    }
    
    return resultMArr;
}

-(NSArray *)YJ_saveTable:(NSString *)tableName dicOrModelArray:(NSArray *)dicOrModelArray{
    int errorIndex = 0;
    NSMutableArray *resultMArr = [NSMutableArray arrayWithCapacity:0];
    NSArray *columnArr = [self getColumnArr:tableName db:_db];
    for (id parameters in dicOrModelArray) {
        
        BOOL flag = [self insertTable:tableName dicOrModel:parameters columnArr:columnArr];
        if (!flag) {
            [resultMArr addObject:@(errorIndex)];
        }
        errorIndex++;
    }
    
    return resultMArr;
}

-(BOOL)YJ_deleteTable:(NSString *)tableName{
    NSString *sqlstr = [NSString stringWithFormat:@"DROP TABLE %@", tableName];
    if (![_db executeUpdate:sqlstr])
    {
        return NO;
    }
    return YES;
}


-(BOOL)YJ_deleteAllDataFromTable:(NSString *)tableName{
    NSString *sqlstr = [NSString stringWithFormat:@"DELETE FROM %@", tableName];
    if (![_db executeUpdate:sqlstr])
    {
        return NO;
    }
    
    return YES;
}

-(BOOL)YJ_isExistTable:(NSString *)tableName{
    FMResultSet *set = [_db executeQuery:@"SELECT count(*) as 'count' FROM sqlite_master WHERE type ='table' and name = ?", tableName];
    while ([set next])
    {
        NSInteger count = [set intForColumn:@"count"];
        if (count == 0) {
            return NO;
        } else {
            return YES;
        }
    }
    return NO;
}

-(NSArray *)YJ_columnNameArray:(NSString *)tableName{
    return [self getColumnArr:tableName db:_db];
}

-(int)YJ_tableItemCount:(NSString *)tableName{
    NSString *sqlstr = [NSString stringWithFormat:@"SELECT count(*) as 'count' FROM %@", tableName];
    FMResultSet *set = [_db executeQuery:sqlstr];
    while ([set next])
    {
        return [set intForColumn:@"count"];
    }
    return 0;
}
- (void)close
{
    [_db close];
}

- (void)open
{
    [_db open];
}

-(NSInteger)lastInsertPrimaryKeyId:(NSString *)tableName{
    NSString *sqlstr = [NSString stringWithFormat:@"SELECT * FROM %@ where pkid = (SELECT max(pkid) FROM %@)", tableName, tableName];
    FMResultSet *set = [_db executeQuery:sqlstr];
    while ([set next])
    {
        return [set longLongIntForColumn:@"pkid"];
    }
    return 0;
}

-(BOOL)YJ_alterTable:(NSString *)tableName dicOrModel:(id)parameters{
    return [self YJ_alterTable:tableName dicOrModel:parameters excludeName:nil];
}

-(BOOL)YJ_alterTable:(NSString *)tableName dicOrModel:(id)parameters excludeName:(NSArray *)nameArr{
    __block BOOL flag;
    [self YJ_inTransaction:^(BOOL *rollback) {
        if ([parameters isKindOfClass:[NSDictionary class]]) {
            for (NSString *key in parameters) {
                if ([nameArr containsObject:key]) {
                    continue;
                }
                flag = [_db executeUpdate:[NSString stringWithFormat:@"ALTER TABLE %@ ADD COLUMN %@ %@", tableName, key, parameters[key]]];
                if (!flag) {
                    *rollback = YES;
                    return;
                }
            }
            
        } else {
            Class CLS;
            if ([parameters isKindOfClass:[NSString class]]) {
                if (!NSClassFromString(parameters)) {
                    CLS = nil;
                } else {
                    CLS = NSClassFromString(parameters);
                }
            } else if ([parameters isKindOfClass:[NSObject class]]) {
                CLS = [parameters class];
            } else {
                CLS = parameters;
            }
            NSDictionary *modelDic = [self modelToDictionary:CLS excludePropertyName:nameArr];
            NSArray *columnArr = [self getColumnArr:tableName db:_db];
            for (NSString *key in modelDic) {
                if (![columnArr containsObject:key] && ![nameArr containsObject:key]) {
                    flag = [_db executeUpdate:[NSString stringWithFormat:@"ALTER TABLE %@ ADD COLUMN %@ %@", tableName, key, modelDic[key]]];
                    if (!flag) {
                        *rollback = YES;
                        return;
                    }
                }
            }
        }
    }];
    
    return flag;
}


// =============================   线程安全操作    ===============================

-(void)YJ_inDatabase:(void (^)(void))block{
    [[self dbQueue] inDatabase:^(FMDatabase *db) {
        block();
    }];
}

-(void)YJ_inTransaction:(void (^)(BOOL *))block{
    [[self dbQueue] inTransaction:^(FMDatabase *db, BOOL *rollback) {
        block(rollback);
    }];
}

@end

到了这里，基本所有用到FMDB的地方都能根据这些方法凑出来了，接下来会找更牛逼更方便的方法来实现存储功能，敬请期待。。。