Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7994afabedf1f1a03a50ad82b557d1ae52bd25a6c607c9a506f7438cd8e462b' 
  AND token = 'h6KC/ef6tTsnFRGNjrDiu6zevJ3VdT1oR6hsQ/h4VKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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