SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d005ccf98e383ab1991c0f01d4707aba7235814ba2b71b85a633954071f2f45' 
  AND token = 'kNxvAC1yDlnUv1KSC9rGJgwMryBCcTROwVfYszqdTPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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