Sequelize - subquery in where clause

Question

I\'m using Sequelize in my Express app. I need to generate a query that has a subquery in the WHERE clause.

SELECT *
  FROM MyTable
 WH         


        

Answer 1

I have encountered a similar issue in my project. The way I choose to implement it is a bit different for two reasons:

1. If at one point in time Sequelize decides to implement sub queries - the syntax is ready.
2. Use Sequelize protection against SQL injection.

Here is my code snippet, hope it helps.

Sequelize v5

const tempSQL = sequelize.dialect.QueryGenerator.selectQuery('MyOtherTable',{
    attributes: ['fkey'],
    where: {
          field1: 1,
          field2: 2,
          field3: 3
    }})
    .slice(0,-1); // to remove the ';' from the end of the SQL

MyTable.find( {
    where: {
        id: {
              [Sequelize.Op.notIn]: sequelize.literal(`(${tempSQL})`)
        }
    } 
} );

Sequelize v6

const tempSQL = sequelize.dialect.queryGenerator.selectQuery('MyOtherTable',{
    attributes: ['fkey'],
    where: {
          field1: 1,
          field2: 2,
          field3: 3
    }})
    .slice(0,-1); // to remove the ';' from the end of the SQL

MyTable.find( {
    where: {
        id: {
              [Sequelize.Op.notIn]: sequelize.literal(`(${tempSQL})`)
        }
    } 
} );

Some people might choose to not use the tempSQL variable and simply build the SQL inside the find structure (maybe using a helper method?)

I also think this might be the basis for a sub queries extension for sequelize as it uses the same syntax almost.