我有模型:业务,贡献者,反馈。
我已经在反馈和贡献者之间以及反馈和商业之间建立了这样的关系:
Feedback.belongsTo(Business)
Feedback.belongsTo(Contributor)
相应的外键属性被添加到表Feedback中。问题是,如何用来自业务和贡献者表记录的ID填充它们?
此方法仅获得第一条记录。如果使用findAll()
,则无法定义。
for (let assetsUrl of assetUrls) {
...
var businesses = null;
var reviews = null;
...
var timestamp = Math.floor(Date.now() / 1000);
var b_id = await Business.findOne({
attributes: ["id"],
})
var c_id = await Contributor.findOne({
})
businesses = await Business.upsert({
...
last_scraped: timestamp
});
reviews = await Review.upsert(
{
contributor_id: c_id.id,
business_id: b_id.id,
last_scraped: timestamp,
},
)
}
业务模式:
class Business extends Model {}
Business.init(
{
id: {
type: Sequelize.INTEGER,
primaryKey: true,
autoIncrement: true,
},
site: {
type: Sequelize.STRING,
},
name: {
type: Sequelize.STRING,
},
business_type: {
type: Sequelize.STRING,
unique: false,
defaultValue: "",
},
address: {
type: Sequelize.TEXT,
// allowNull defaults to true
},
price: {
type: Sequelize.STRING,
},
url: {
type: Sequelize.STRING,
allowNull: false,
unique: true,
},
last_scraped: {
type: Sequelize.INTEGER,
defaultValue: Math.floor(Date.now() / 1000)
},
},
{
sequelize,
modelName: "business",
timestamps: true,
createdAt: false,
updatedAt: false,
underscored: true
}
);
Business === sequelize.models.Business;
Business.sync();
贡献者模型:
class Contributor extends Model {}
Contributor.init(
{
id: {
type: Sequelize.INTEGER,
primaryKey: true,
autoIncrement: true,
},
site: {
type: Sequelize.STRING,
},
name: {
type: Sequelize.STRING,
unique: false,
},
location: {
type: Sequelize.STRING,
unique: false,
},
photo: {
type: Sequelize.STRING,
unique: false,
},
url: {
type: Sequelize.STRING,
allowNull: false,
unique: true,
},
status: {
type: Sequelize.SMALLINT,
},
last_scraped: {
type: Sequelize.INTEGER,
defaultValue: Math.floor(Date.now() / 1000)
},
},
{
sequelize,
modelName: "contributor",
timestamps: true,
createdAt: false,
updatedAt: false,
underscored: true,
}
);
Contributor === sequelize.models.Contributor;
Contributor.sync();
反馈模型:
class Feedback extends Model {}
Feedback.init(
{
contributor_id: {
type: Sequelize.INTEGER,
},
business_id: {
type: Sequelize.INTEGER,
},
date: {
type: Sequelize.STRING,
unique: false,
},
rating: {
type: Sequelize.STRING,
unique: false,
},
content: {
type: Sequelize.STRING,
unique: false,
},
last_scraped: {
type: Sequelize.INTEGER,
defaultValue: Math.floor(Date.now() / 1000)
},
},
{
sequelize,
modelName: "feedback",
timestamps: true,
createdAt: false,
updatedAt: false,
underscored: true,
}
);
Feedback.belongsTo(Contributor, { foreignKey: 'contributor_id' })
Feedback.belongsTo(Business, { foreignKey: 'business_id'})
Feedback=== sequelize.models.Review;
Feedback.sync();
var feedback = await Feedback.findAll({
attributes: ['contributor_id', 'business_id', 'last_scraped']
})
findOne
与offset
选项结合使用,您可以像这样创建/更新Feedback
模型。// Get number of records to avoid unnecessary findOne in the loop
const bRecordCount = await Business.count();
const cRecordCount = await Contributor.count();
for (let i = 0; i < assetUrls.length; i++) {
const assetsUrl = assetUrls[i];
// ...
let bRecord = null;
let cRecord = null;
let options = {
attributes: ["id"],
// order by id to be sure we get different record each time
order: [['id', 'ASC']],
raw: true,
offset: i //skip already taken records
};
try {
if (i < bRecordCount && i < cRecordCount) {
bRecord = await Business.findOne(options)
cRecord = await Contributor.findOne(options)
}
if (bRecord && cRecord) {
feedback = await Feedback.upsert({
contributor_id: cRecord.id,
business_id: bRecord.id,
last_scraped: timestamp,
//...
});
}
} catch (err) {
console.log(err);
}
}
如果您有很多记录,则应考虑使用findAll()
通过findAll()
和offset
选项,然后做一个limit
bulkCreate()
选项可以避免进行很多数据库查询