Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a6335a33f1c83a4c1d5ce2d64c574f35aed60f0ce221cfd412850c1a59ce9e9e' 
  AND token = 'Fk2hlEWvakFSKV60SnFwR5BPDWAHqUaN0g+CcmEy6Xg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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