Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ee6a11fe9bd14406a5d1f73a3ed94dd41ac3376ddfd6476ab0655f8cc2b9cf2' 
  AND token = 'Ps/Kl1ILS7n8f1wP8ZuF2Jzi638or4wEjtCKn+1ILmM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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