如何从ORMLITE删除记录? [英] how to delete a record from ORMLITE?

问题描述

我需要从ORMLite数据库中删除一条记录，我可以使用id删除一条记录，如下所示:

I need to delete a record from ORMLite Database I can delete a record by id using as below

@Override
public void Delete(int id) throws SQLException {
    this.dao.deleteById(id);
}

但是如果我必须从同一个表中删除一条记录，而不是通过ID而是通过名称或任何其他字段，该怎么办?我想要类似

but what if I have to delete a record from same table not by id but by name or any other field I want something like

public void Deletefromcanteen(String name,MealType mealtype) {
    this.dao.deletebyName(name);
}

我应该使用querybuilder编写什么查询来删除其中name = name and mealtype = say(午餐)的记录

what query should i write using querybuilder to delete a record where name = name and mealtype = say (lunch)

我在databasehelper类中尝试过类似的操作

I tried something like this in my databasehelper class

public  void deletefromcanteen(int id, String mealtype) {
    try {
        Dao<CanteenLog, Integer> canteenDao = getCanteen();
        DeleteBuilder<CanteenLog, Integer> deleteBuilder = canteenDao
                .deleteBuilder();
        deleteBuilder.where().eq("user_id", id).and().eq("meal", mealtype);
        canteenDao.delete(deleteBuilder.prepare());
    } catch (Exception e) {
        ...
    }
}

推荐答案

deleteBuilder.where().eq("FIELD_NAME", arg);
deleteBuilder.delete();

更新:

例如:

//Get helper
DatabaseHelper helper = OpenHelperManager.getHelper(App.getContext(), DatabaseHelper.class);

//get dao
Dao dao = helper.getDao(YOUR_CLASS.class);

//delete elements from table in field by arg
DeleteBuilder<CanteenLog, Integer> deleteBuilder = dao.deleteBuilder();
deleteBuilder.where().eq("FIELD_NAME", arg);
deleteBuilder.delete();

祝你好运！

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