SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b791b2d238e85a4a35a2359535333f048e5428541c24134a6e042c34aeb297a5' 
  AND token = '9Syl8DRNkoeyamjZIL9VQJogQ5Fq1L6eHP8PwXKK32M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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