SELECT 
  quickpay_id 
FROM 
  cscart_jp_cc_quickpay 
WHERE 
  user_id = 0 
  AND payment_method = 'remise_cc'

Query time 0.00004

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}