如何在ormlite中保存带有“异物"的对象 [英] how to save an object with 'foreign object' in ormlite

问题描述

这是我的数据库:

创建表其他(id 整数主键自增不为空，文本文本);CREATE TABLE tabela(campoid INTEGER 主键自动增量不为空，camponome 文本不为空，chave int，外键(chave)引用其他(id))；

这是我的课程:

@DatabaseTable(tableName = "tabela")公共类豆{@DatabaseField(columnName = "campoid",generatedId = true)私有整数_id；@DatabaseField(columnName = "camponome")私人字符串名称；@DatabaseField(foreign = true, columnName = "chave", canBeNull = false)私人部分chave;}

和其他类映射

@DatabaseTable(tableName = "other")公共课部分{@DatabaseField(generatedId = true, columnName = "id")私有整数 ID；@DatabaseField(columnName = "texto")私人字符串文本；}

但是当我保存一个 Bean 对象时，对象部分"也不会保存:(

 Helper helper = OpenHelperManager.getHelper(this, Helper.class);Dao<Bean, Integer>dao = helper.getDao(Bean.class);Bean firstBean = new Bean();firstBean.setNome("首先被持久化");部分部分=新部分()；part.setTexto("任何文本");firstBean.setChave(part);dao.create(firstBean);

在我的日志中:

07-13 00:25:26.602: D/BaseMappedStatement(3796): 用语句插入数据 'INSERT INTO tabela (camponome ,chave ) VALUES (?,?)' 和 2 个参数，更改了 1 行

有什么想法吗?

解决方案

但是当我保存一个 Bean 对象时，对象部分"也不会保存:(

没错.ORMLite 在您创建对象时默认不会持久化子对象.您可以打开 foreignAutoCreate = true 标志，这将为您执行此操作.请参阅 javadocs for foreignAutoCreate.

您的 chave 字段应定义为:

@DatabaseField(foreign = true, columnName = "chave", canBeNull = false,外国自动创建 = 真)私人部分chave;

如果您想手动完成，您应该:

partDao.create(firstBean.chave);beanDao.create(firstBean);

您首先在数据库中创建Part，因为您需要来自Part 的ID，该ID 将保存到您的bean 中.

This is my database:

CREATE TABLE other (
    id integer primary key autoincrement not null,
    texto text
);

CREATE TABLE tabela (campoid INTEGER primary key autoincrement not null, 
                        camponome text not null, chave int,
                        foreign key (chave) references other(id));

and this is my classes:

@DatabaseTable(tableName = "tabela")
public class Bean {

    @DatabaseField(columnName = "campoid", generatedId = true)
    private int _id;

    @DatabaseField(columnName = "camponome")
    private String nome;

    @DatabaseField(foreign = true, columnName = "chave", canBeNull = false)
    private Part chave;
}

and other classe mapped

@DatabaseTable(tableName = "other")
public class Part {

    @DatabaseField(generatedId = true, columnName = "id")
    private Integer id;

    @DatabaseField(columnName = "texto")
    private String texto;
}

but when i save an Bean object, the Object 'part' does not save too :(

        Helper helper = OpenHelperManager.getHelper(this, Helper.class);
        Dao<Bean, Integer> dao = helper.getDao(Bean.class);

        Bean firstBean = new Bean();
        firstBean.setNome("first be persisted");

        Part part = new Part();
        part.setTexto("ANY TEXT");
        firstBean.setChave(part);

        dao.create(firstBean);

in my log:

07-13 00:25:26.602: D/BaseMappedStatement(3796): insert data with statement 'INSERT INTO tabela (camponome ,chave ) VALUES (?,?)' and 2 args, changed 1 rows

any idea?

解决方案

but when i save an Bean object, the Object 'part' does not save too :(

Right. ORMLite does not by default persist sub-objects when you create an object. You can turn on the foreignAutoCreate = true flag which will do that for you however. See the javadocs for foreignAutoCreate.

Your chave field should be defined then as:

@DatabaseField(foreign = true, columnName = "chave", canBeNull = false,
    foreignAutoCreate = true)
private Part chave;

If you want to do it by hand, you should:

partDao.create(firstBean.chave);
beanDao.create(firstBean);

You create the Part in the database first because you need the ID from the Part which will be saved into your bean.

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