SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'faf29b03aeddf7307deca8723f32718a6bbe7c2d590ba432065bf304486f5c06' 
  AND token = 'Zw9HVdBRkJVqrY3P0P/NMcFJw86fA23pTRpngV+T7Z0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}