SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7039f063a80e3a520ab56dd90a7ff2705c4e432f8561685f3134d1e3b48dc246' 
  AND token = '5wbEcBOVjmoqXAO7Dmt0YxFOFm/UWManpZXwqo2Ci6c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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