SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b8e0491d3c84104ded8d25affe47615648d5ac316e233a8b26b220647511f77' 
  AND token = 'JmJt0zWnPmJ5870wCYJRZszhM50YOajoWvEMiGKyNEM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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