SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25019a2ebd38b2309dbc3f15e4cb96df4d52afd7164f80f77e6d80efb1f463ae' 
  AND token = 'k+03hvgrL3vQ36ULLZpCmXW8uYz/5bBk66DLQ1wYzUE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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