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How to change connection for reports?

edited December 2003 in End User
I made a bunch of reports using ADOExpress for testing and I cannot open
them using another type of connection components. It seems to expect the
ADOExpress DADE classes to be present and usable.
How can I change the connection a report is bound to, to something else?
I saved the reports as rtms and I see they are text files ala dfm, but I am
sure there's a better way than replacing text inside those (which is quite a
bit) :-) Can anybody help me? Thanks!

--
Best regards,
Alessandro Federici

RemObjects Software, Inc.
http://www.remobjects.com

Comments

  • edited December 2003

    To clarify the question for anyone else reading this:

    1. Data Connection

    A data connection for ADO is defined by a TADOConnection component. Create a
    TADOConnection and assign it to the Designer.DataSettings. Now each new
    DataView that you create will be assigned that connection name. This enables
    the connection parameters to be modified at a later time.

    2. DADE Plug-ins = Data Access Components

    Each DADE plug-in implements a set of classes that support a specific type
    of data access components: ADO, BDE, IBExpress, etc. The current DataView
    architecture does not provide a simple way to convert from one type of data
    access components to another. The issue is somewhat similar to the case in
    which you place a TTable on a Delphi form and later want to change it to a
    TADOTable. The TTable is saved in the .dfm file.

    3. The following article contains guidelines for converting templates to use
    a different type of DADE plug-in.


    -------------------------------------------------
    Tech Tip: Convert BDE Template Dataviews To ADO
    -------------------------------------------------

    Currently when DADE is used to create dataviews, the DatabaseName is stored
    as part of the query definition. (This is consistent with Delphi's approach
    to specifying a database connection for a Query object).

    When you created the reports originally, the daDBBDE.pas BDE DADE plugin was
    used. Now you want to use ADO. You've already changed the
    Designer.Datasettings but this had no effect on the old reports. They still
    try to use the BDE connection. Changing the Designer.DAtaSettings only works
    for new dataviews that are created, because the new query dataviews are
    using the daADO.pas ADO DADE plugin.

    In order to convert the templates from BDE to ADO, at the minimum you have
    to change the database name and the DADE plugin class names that are stored
    in the templates. When a BDE dataview is created, its class type is a
    TdaBDEQueryDataview. When an ADO dataview is created, its class type is
    TdaADOQueryDataview. These class types are stored in the template. These
    have to be changed before the template is loaded into a report.

    First, compare a BDE report template to an ADO report template which both
    connect to the same database table. Save a BDE and an ADO based report
    template to separate ASCII text files. Now compare the dataview definitions.
    Change the TdaBDEQueryDataview class name to TdaADOQueryDataview in the BDE
    template. Change the BDE alias to your ADOConnection object. Then compare
    the table name and field names of the BDE template to the ADO template and
    change them accordingly, removing the .db extension on the table name is
    necessary. Now load the converted BDE template in your ADO end user
    application.

    The first step is to make a backup of all your templates before continuing
    with a programatic approach. You can convert the templates programatically
    by loading the ASCII template files to a TStringList object. Then loop
    through the lines of the list and change the text programatically. You can
    loop through the files in a directory using ppFileUtils.pas calling the
    GetFileNamesForDirectory procedure to load the file names.

    If you have binary report templates, you'll also be able to convert these
    with an extra couple of steps. You can load the binary template file into
    ASCII format, modify it, and then save it back to binary as shown in the
    example links below. Keep in mind the conversion is performed without
    loading the report template into a TppReport.


    This example shows how to load reports stored to the ReportExplorer database
    tables and convert them to ascii text.

    http://www.digital-metaphors.com/tips/EditTemplatesAsText.zip


    This example shows how to convert an .rtm file to asii text


    http://www.digital-metaphors.com/tips/ConvertBinaryTemplateToASCII.zip



    --
    Tech Support mailto:support@digital-metaphors.com
    Digital Metaphors http://www.digital-metaphors.com


    --
    Nard Moseley
    Digital Metaphors
    http://www.digital-metaphors.com
    "Alessandro Federici [RemObjects Software]"

    Best regards,

    Nard Moseley
    Digital Metaphors
    www.digital-metaphors.com
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