SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31a63af4d7a720ef870dab7292d71895d5d579065ba7faee10493894940cd122' 
  AND token = 'hjHaO4cVyiJk414hwlCbm5jKgRUk7a1mZOowfCRxDMc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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