SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a93f9ddf083efbefa683dfa8a36efaba459444b0a5f5cf16bbce8894ad108290' 
  AND token = 'Y85YJLPSmeFEJE2XpbGiMhMwmTFFXikDmpeWgFwcFUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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