SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '753e85bfc25ce78ca94d4a830de5f09e973a1eae7a1bfaef4b7cc3bf1e75289f' 
  AND token = 'hYsOR7zrjomL/tagceCD8f5HOhtzC8DqQw+mkCojuQM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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