SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a74a85cde27c629186e8270d82700d76d24de730744526c75849e5572b826ae0' 
  AND token = 'lfKgvQHeA6NZMVbdoII09mIrcXbLESB9c4Qj0H9GtCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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