SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '98df077079f6381bf2fe623fe27fa2991df61a32bf7faf41d8f2108ac3ef5c74' 
  AND token = 'eP4gdDqFRsQD7EB/IGa3TWJHvunqjczgwRquC1DFakU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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