SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02a0c8483e98e438d23788dd39bccb2782b5961bcb633da69c231eb6ba6987ff' 
  AND token = 'JwJK8oBSY2DRYHE9DauK4o7ggCSxOIVmwD5Vht6iBug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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