SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e076f989412212e82faaec55bf18fc149a8672c1b5d70b9ba28bdcc4f869d00a' 
  AND token = '++MJP/7hS8X11TATezBecD+C1bV63/Kqw9Gc2ZJUnoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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