SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '596b9eae017dedfad66b38225eb57f7aaf67e6e098ca5885a731849ac761944e' 
  AND token = 'Zii5M09IJ5cDJhdE7IVJyCOxXcJ4Osxaj40dJbfPSas=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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