SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5afd4b47beadbfd9457b0ba757f67fcf96fbbbc6c72d6350af567a2b15afdd16' 
  AND token = 'm42BNmcmwFqPyO1o/MYM0HpLAXXisr2zrJn5H6WkbWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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