Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '71ec5a89875191f472988f7cf5163f163b41237bdf8c4838a3cdd90fed01df5e' 
  AND token = 'UPSDjy/uokSlbfQH+Pmbcm7+Qvy9VmQhFRz711BaLv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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