SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '238074ac2067c17513cc8475e96a5b8b26d7132b4c9550ba086687cb682d23af' 
  AND token = 'fyJzzQStYev9/GHn2DZrKOuG5TGHVwpNjyRHboPSQwo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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