SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38cc05a4df95acc62879fdb18253ffab9a04572496968b0f21ec3e3ae7736ea4' 
  AND token = 'NDA2vG2GIRPMiLTslZkUZdLuZYIRrN1ISqKqDsnBeQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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