SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f659b467f2fa398f00b87387d3d3e3340e9857075553743fc52a73fa4f47974f' 
  AND token = 'TXsetRdupCnlROZ14mYl7OCzDsM9GSK6BVbcAwvyoqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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