SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '070ac515cd0bf87766c6df618012f8c7f75dff67a6e6c2492996c89153a0eb73' 
  AND token = 'vGKjEgw+XOllNpR8/eBAFKtuOIhZtrDDQ2N6u9+1VLM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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