How to concatenate sequelize results?

Question

In my node.js application, I call a sequelize query, and inside its .then() I call another sequelize query. I want the result of the second query to be appended to the first query so that it can be returned as a JSON with a JSON Array inside it. how can this be done?

{
    result1,
    result2[
    ...
    ]
}

Answer 1

You can append two result sets into an array, roughly as follows:

    let myResult = [];     // container for two results

    SomeModel.findAll({
      where: {'someField' : { [Op.like]: '%b%' }}
    }).then(firstResultSet => {

        myResult.push(firstResultSet);   

        SomeOtherModel.findAll(
          {where: {'someField' : { [Op.like]: '%a%' }
        }).then(secondResultSet=> {

            myResult.push(secondResultSet);
            result.send(myResult);
            next();

        });
    })   

Answer 2

Using Promise.all and the ES6 array spread will give you a nice clean implementation. Note that if your arrays are of different types you'll find it challenging to reliably iterate over your final result.

const Some = SomeModel.findAll({ where: {'someField': { [Op.like]: '%b%' }} });
const Other = OtherModel.findAll({ where: {'someField': { [Op.like]: '%a%' }} });

Promise.all([Some, Other]).then([some, other] => [...some, ...other]);

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/all https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax