SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f507db6f511db464d93984842bf7d301164966db115133db5a1b2d81f0db97d' 
  AND token = 'uX4gLFzuQ0AFKx0Svm3OzXR28vU+IBlQ5rGTuk8PhZA=' 
  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"
    }
  }
}