SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8bb8c608c620cee8dce00f8dd3993d5abda97c3fbcb5c985831e654ea6ee2a08' 
  AND token = 'sKElrhG5M6/kfVHvCoUm8Nihgt5WQJbewWZfz8341vk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}