问题 I meet a problem when I import data in an ios app. The data is stored with coredata. I was trying to import the data with a button. After it is clicked, the data, which is firstly stored in a txt file in JSON format will be stored in the sqllite file. My question is this, it is very slow to import such amount of data and it is not friendly for user to click button or wait to import the initial data. Is there a better way to import data? Thanks. 回答1: It depends. For example you could just