SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7670cc63338a86ef1b3bf585bdaab7efa3eb6075b683750ec114e90c53a36b7' 
  AND token = 'lchnixruHSn0VizGN2825a/7chRVS1Prji7LqYVCsC8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}