Update multiple rows in sequelize with different c

问题:

I'm trying to perform an update command with sequelize on rows in a postgres database. I need to be able to update multiple rows that have different conditions with the same value.

For example, assume I have a user table that contains the following fields:

• ID
• First Name
• Last Name
• Gender
• Location
• createdAt

Assume, I have 4 records in this table, I want to update records with ID - 1 and 4 with a new location say Nigeria.

Something like this: SET field1 = 'foo' WHERE id = 1, SET field1 = 'bar' WHERE id = 2

How can I achieve that with sequelize?

回答1:

You can update multiple record at a time , but same updates for all records , if you want to make different updates for different conditons then you have to run that multiple time

Example :

This will update fields1 to foo , where id is 1 or 4

let ids = [1,4];
Your_model.update({ field1 : 'foo' },{ where : { id : ids }}); 

This will update field1 to foo if id is 1 , and field1 to bar if id is 4

Your_model.update({ field1 : 'foo' },{ where : { id : 1 }});
Your_model.update({ field1 : 'bar' },{ where : { id : 4 }}); 

Hope this will clear all your doubts.

回答2:

You can update multiple rows following your conditions, and to do that the operators are very helpful.

Look here: http://docs.sequelizejs.com/manual/querying.html (operators)

const { Op } = Sequelize;
DisplayMedia.update(
    {
        field: 'bar'
    },
    {
        where: {
            id: {
                [Op.in]: [1, 10, 15, ..]   // this will update all the records 
            }                           // with an id from the list
        }
    }
)

There is all kinds of operators, including the range operators, or like operator ...etc

Also one of the important questions when it come to update, is how to update all rows?

Not including where results in an error "Missing where attribute in the options parameter passed to update".

The answer is in the code bellow: provide a where with an empty object.

await DisplayMediaSequence.update({
    default: false
}, {
    where: {}, // <-- here
    transaction
});
await DisplayMediaSequence.update({ 
    default: true     <-- after all turned to false, we now set the new default. (that to show a practical expample) -->
}, {
    where: {
        id
    },
    transaction
});