SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4e093aa98b83d2908c59664885e7480424f33fbd5a8605fcedea8fffae6a879' 
  AND token = '4odjm0wZ0hZeHxwczcHtyEisqp6gySbAAgQ7DbsBXmY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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