数据库操作

FMDB

• 创建数据库

// 需要先创建数据库文件保存目录
if (![fileManager fileExistsAtPath:myPath]) {
        [fileManager createDirectoryAtPath:myPath withIntermediateDirectories:YES attributes:nil error:nil];
    }
// 拼接数据库路径
NSString *dbPath = [maskFilePath stringByAppendingPathComponent:@"user.sqlite"];
// 创建数据库
_dataBase = [FMDatabase databaseWithPath:dbPath];

• 创建表

NSString *sql = [NSString stringWithFormat:@"CREATE TABLE IF NOT EXISTS UserDataTable(u_id INTEGER PRIMARY KEY AUTOINCREMENT,  u_address TEXT)"];
BOOL result = [_dataBase executeUpdate:sql];

• 增

• 删

• 改

• 查

• 索引

 [db executeUpdate:DDYStrFormat(@"CREATE INDEX IF NOT EXISTS index2 ON %@ (messageID)",tableName)];

• 事务

• 多表联查