SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49550c14bb5f33f198d8a6a33eb13807fb58625bed20dbf07265ebd9716fa27d' 
  AND token = 'cuq5Uius/WBv9iBnQzsAdrcQLv4sJDSlNbSyXZwKxaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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