AspenTech InfoPlus 21 - How to connect and query data

InfoPlus21 is process historian containing list of templates of different tag structure e.g. IP_AnalogDef, IP_DescreteDef, IP_TextDef etc. Based on process tags from DCS/OPC/Any other historian, the IP21 records are created and each record acts as a table in historian.

ANS1: Aspentech software is only windows based compatibility however IP21 aspenONE Process Explorer is web based and therefore you can access it over any operating system using host url.

ANS2:

you can try SELECT statement to get data from IP21 Historian using it's end-user component SQLPlus or on excel add-ins. e.g.

SELECT NAME, IP_DESCRIPTION, IP_PLANT_AREA, IP_ENG_UNITS FROM IP_ANALOGDEF  

RESULTS:

I hope this help you understand better. Otherwise you need to first learn the structure of your IP21 historian tags to build the query e.g. If it has customized structure, then you have to build your own.

Welcome in industrial-IT !
For these technology, the best option is the 'AspenTech SqlPlus ODBC driver'.

That been said, you are talking about an endpoint on a fairly old IP21 server, so I suppose it is something like http://.../SQLPlusWebService/SQLplusWebService.asmx.
In that case, it is the SOAP wrapper around SqlPlus: you will not have to install the Windows ODBC driver... But you will still have to learn SqlPlus syntax.

In order to have more information about it, you can ask AspenTech, also you can install the SqlPlus client 'Aspen SqlPlus', and check the help file in "C:\Program Files (x86)\AspenTech\InfoPlus.21\db21\code\ipsqlplus.chm"

EDIT: here is an example in c#, to list all records:

    static void Main(string[] args)
    {
    const string SERVER_HOST = "SERVERHOST";
    const string SERVER_URL = "http://{0}/SQLPlusWebService/SQLplusWebService.asmx";

    const string SOAP12 =
        "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
        + "<soap12:Envelope xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:soap12=\"http://www.w3.org/2003/05/soap-envelope\">"
        + "<soap12:Body>"
        + "<ExecuteSQL xmlns=\"http://www.aspentech.com/SQLplus.WebService/\">"
        + "<command>{0}</command>"
        + "</ExecuteSQL>"
        + "</soap12:Body>"
        + "</soap12:Envelope>";

    const string SQLPLUS_COMMAND_ALLRECORDS =
        "SELECT * FROM all_records";

    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(
        string.Format(SERVER_URL, SERVER_HOST));
    // If required by the server, set the credentials.
    request.Credentials = CredentialCache.DefaultCredentials;

    request.ContentType = "application/soap+xml; charset=utf-8";
    request.Method = "POST";

    XmlDocument soapEnvelopeDocument;
    soapEnvelopeDocument = new XmlDocument();
    soapEnvelopeDocument.LoadXml(string.Format(SOAP12, SQLPLUS_COMMAND_ALLRECORDS));

    byte[] bytes;
    bytes = Encoding.UTF8.GetBytes(soapEnvelopeDocument.OuterXml);
    request.ContentLength = bytes.Length;
    using (Stream stream = request.GetRequestStream())
    {
        stream.Write(bytes, 0, bytes.Length);
    }

    // Get the response.
    HttpWebResponse response = (HttpWebResponse)request.GetResponse();
    // Display the status.
    Console.WriteLine(response.StatusDescription);
    // Get the stream containing content returned by the server.
    Stream dataStream = response.GetResponseStream();
    // Open the stream using a StreamReader for easy access.
    StreamReader reader = new StreamReader(dataStream);
    // Read the content.
    string responseFromServer = reader.ReadToEnd();
    // Display the content.
    Console.WriteLine(responseFromServer);
    // Cleanup the streams and the response.
    reader.Close();
    dataStream.Close();
    response.Close();

}