Duplicate keys in "IN", relational calls

[graphql]

Duplicate keys in "IN", relational calls

[alexandrebodin]

@Epenance Do you have cache disabled ?

If so we are currently discussing some changes that match your needs at #44

[eugene1g]

Not sure about graphql-sequelize, but I handle this in the resolver function with something like this -

import keyBy from 'lodash/keyBy'
import uniq from 'lodash/uniq'
import squel form 'squel'
import pg from 'pg-promise'
//...
const loadRecords = async (askedKeys) => {
  const query = squel.select().from('person').where('id in ?', uniq(askedKeys)).toString()
  const dbRows = await pg.any(query)
  const byId = keyBy(dbRows, row => row.id)
  return askedKeys.map(id => byId[ id ] || null)
}

const myLoader = new DataLoader(loadRecords)

This approach works, however #46 is neater because it handles race condition better.

[leebyron]

Closing this aging issue

I'll work on getting #46 polished up and ready to land since that would fix this issue, though I encourage either not turning off caching or doing this deduping within your batch function.