SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '469cf428689723dcf35888896c5653f3bca2da8756577c8f54d3f8ed73dfdae1' 
  AND token = '7i09Vuw5cYbkxpGec2j+4HlNsWguuP+EfkxP1NtLFcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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