Interface. Batch Update Data

12003

In certain scenarios, you may need to batch update multiple records in the database. jianghuKnex supports batch update operations in both the front-end page and the API. Here are two methods to implement batch updates:

Batch Update in the Page: Use a for loop to call the SQL resource in the front-end page.
Batch Update in the API: Perform a for loop update in the back-end service, or calculate the difference list and then use Promise.all for the update.

Batch Update in the Page

• Call SQL resource in a for loop within the page

const studentList = [{studentId: 'S10001', studentStatus: 'Normal'}, {studentId: 'S10003', studentStatus: 'Graduated' }];
for (const item of studentList) {
    await window.jianghuAxios({
        data: {
            appData: {
                pageId: 'frontendDemo',
                actionId: 'updateItem',
                actionData: { studentStatus: item.studentStatus },
                where: { studentId: item.studentId }
            }
      }
  })
}

Batch Update in the API

• Call a service interface in the page, and use a for loop to update in the service interface

const studentList = [{studentId: 'S10001', studentStatus: 'Normal'}, {studentId: 'S10003', studentStatus: 'Graduated' }];
await this.app.jianghuKnex.transaction(async trx => {
    for (const item of studentList) {
        await trx("student", this.ctx)
            .where({ studentId: item.studentId })
            .jhUpdate({ studentStatus: item.studentStatus });
    }
})

• Note: If the batch update exceeds 20 records, it is recommended to calculate the diffList and then use Promise.all for the update

const newStudentList = [{studentId: 'S10004', studentStatus: 'Graduated'}, {studentId: 'S10005', studentStatus: 'Graduated' }];
const studentIdList = newStudentList.map(item => item.studentId);
const oldStudentList = await this.app.jianghuKnex("student").whereIn('studentId', studentIdList).select();
const diffStudentList = newStudentList.filter(newStudent => {
    const oldStudent = oldStudentList.find(item => item.studentId === newStudent.studentId);
    if (newStudent.studentStatus != oldStudent.studentStatus) { return true; }
    return false;
});
if (diffStudentList.length > 0) {
    await this.app.jianghuKnex.transaction(async trx => {
        const queries = diffStudentList.map(diffItem =>
            trx("student", this.ctx)
                .where({ studentId: diffItem.studentId })
                .update({ studentStatus: diffItem.studentStatus })
        );
        await Promise
            .all(queries).then(trx.commit)
            .catch((err) => {
                logger.error("[jianghuKnex.transaction error]", err);
                throw err;
            });
    });
}