---
tags: music-library,solution,track
---

# Postgres music-library: PATCH /artists

const updateArtist = async (req, res) => {
  const { id } = req.params
  const { name, genre } = req.body
  
  let query, params
  
  if (name && genre) {
      query = `UPDATE Artists SET name = $1, genre = $2 WHERE id = $3 RETURNING *`
      params = [name, genre, id]
  } else if (name) {
      query = `UPDATE Artists SET name = $1 WHERE id = $2 RETURNING *`
      params = [name, id]
  } else if (genre) {
      query = `UPDATE Artists SET genre = $1 WHERE id = $2 RETURNING *`
      params = [genre, id]
  }

  try {

    const { rows: [ artist ] } = await db.query(query, params)

    if (!artist) {
      return res.status(404).json({ message: `artist ${id} does not exist` })
    }

    res.status(200).json(artist)
  } catch (err) {
    console.log(err)
    res.status(500).json(err.message)
  }
}

module.exports = { 
    ..., 
    ..., 
    ..., 
    updateArtist
}