Announcement

Collapse

The Alpha Software Forum Participation Guidelines

The Alpha Software Forum is a free forum created for Alpha Software Developer Community to ask for help, exchange ideas, and share solutions. Alpha Software strives to create an environment where all members of the community can feel safe to participate. In order to ensure the Alpha Software Forum is a place where all feel welcome, forum participants are expected to behave as follows:
  • Be professional in your conduct
  • Be kind to others
  • Be constructive when giving feedback
  • Be open to new ideas and suggestions
  • Stay on topic


Be sure all comments and threads you post are respectful. Posts that contain any of the following content will be considered a violation of your agreement as a member of the Alpha Software Forum Community and will be moderated:
  • Spam.
  • Vulgar language.
  • Quotes from private conversations without permission, including pricing and other sales related discussions.
  • Personal attacks, insults, or subtle put-downs.
  • Harassment, bullying, threatening, mocking, shaming, or deriding anyone.
  • Sexist, racist, homophobic, transphobic, ableist, or otherwise discriminatory jokes and language.
  • Sexually explicit or violent material, links, or language.
  • Pirated, hacked, or copyright-infringing material.
  • Encouraging of others to engage in the above behaviors.


If a thread or post is found to contain any of the content outlined above, a moderator may choose to take one of the following actions:
  • Remove the Post or Thread - the content is removed from the forum.
  • Place the User in Moderation - all posts and new threads must be approved by a moderator before they are posted.
  • Temporarily Ban the User - user is banned from forum for a period of time.
  • Permanently Ban the User - user is permanently banned from the forum.


Moderators may also rename posts and threads if they are too generic or do not property reflect the content.

Moderators may move threads if they have been posted in the incorrect forum.

Threads/Posts questioning specific moderator decisions or actions (such as "why was a user banned?") are not allowed and will be removed.

The owners of Alpha Software Corporation (Forum Owner) reserve the right to remove, edit, move, or close any thread for any reason; or ban any forum member without notice, reason, or explanation.

Community members are encouraged to click the "Report Post" icon in the lower left of a given post if they feel the post is in violation of the rules. This will alert the Moderators to take a look.

Alpha Software Corporation may amend the guidelines from time to time and may also vary the procedures it sets out where appropriate in a particular case. Your agreement to comply with the guidelines will be deemed agreement to any changes to it.



Bonus TIPS for Successful Posting

Try a Search First
It is highly recommended that a Search be done on your topic before posting, as many questions have been answered in prior posts. As with any search engine, the shorter the search term, the more "hits" will be returned, but the more specific the search term is, the greater the relevance of those "hits". Searching for "table" might well return every message on the board while "tablesum" would greatly restrict the number of messages returned.

When you do post
First, make sure you are posting your question in the correct forum. For example, if you post an issue regarding Desktop applications on the Mobile & Browser Applications board , not only will your question not be seen by the appropriate audience, it may also be removed or relocated.

The more detail you provide about your problem or question, the more likely someone is to understand your request and be able to help. A sample database with a minimum of records (and its support files, zipped together) will make it much easier to diagnose issues with your application. Screen shots of error messages are especially helpful.

When explaining how to reproduce your problem, please be as detailed as possible. Describe every step, click-by-click and keypress-by-keypress. Otherwise when others try to duplicate your problem, they may do something slightly different and end up with different results.

A note about attachments
You may only attach one file to each message. Attachment file size is limited to 2MB. If you need to include several files, you may do so by zipping them into a single archive.

If you forgot to attach your files to your post, please do NOT create a new thread. Instead, reply to your original message and attach the file there.

When attaching screen shots, it is best to attach an image file (.BMP, .JPG, .GIF, .PNG, etc.) or a zip file of several images, as opposed to a Word document containing the screen shots. Because Word documents are prone to viruses, many message board users will not open your Word file, therefore limiting their ability to help you.

Similarly, if you are uploading a zipped archive, you should simply create a .ZIP file and not a self-extracting .EXE as many users will not run your EXE file.
See more
See less

Data Sets

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Data Sets

    I have a primary table that links to a secondary table on a one-to-many link.
    All columns to link to are contained in the primary table, with the exception of the first column in the secondary table which contains a 3-char record type ("SYM").

    How do I create the link?

  • #2
    Re: Data Sets

    Hi, Selwyn.

    Are you working with native Alpha Five tables?

    If so, typically the values used to link records between the two tables must be present in both tables. In your case a value you want to use as a link is present in only one table. Can that value be "computed" or "derived" from other fields in the primary table?

    Comment


    • #3
      Re: Data Sets

      Hi Tom

      I am working with MySQL tables.

      At present there is no data on the primary record to compute or derive the field value to be used to link to the secondary record.

      However the record type for the secondary table can be calculated or derived as all the records in the secondary table have the same record type.
      E.g field name SymGroup. The first 3-characters for every record in its table has a record type of "SYM".

      If this cannot be resolved it is possible to add an additional column to the primary record containing "SYM" and pass this column in the linkage. Here I would appreciate some assistance to set this value dynamically in the new primary column prior to the link taking place. Then columns could be used in the linkage.

      I note that there is also provision for an expression to use in the linking. However I can't find any documentation on the use of the expression in a multi-column link.

      Tx
      Selwyn

      Comment


      • #4
        Re: Data Sets

        Perhaps others will be able to assist. I have no experience with mySQL.

        Comment


        • #5
          Re: Data Sets

          Thanks anyway.
          How would you do this assuming the files were native alpha dbf?
          Selwyn
          Last edited by Selwyn Oster; 03-21-2014, 09:38 AM. Reason: Further question

          Comment


          • #6
            Re: Data Sets

            There are a number of ways.
            Easiest is to have the linking field in both tables.
            Table 1 SYM matches Table 2 SYM
            You can link on multiple fields in the same manner as long as they are present in both.
            The field names do not have to be the same, but the Data Type and Length does.

            Next is with Expressions.
            Suppose you want to link on Name and Number and Date
            Then the expression could be Name+str(Number)+dtoc(Date) which would give you "Billy123401/01/1900"
            You can easily test your expressions in the Interactive Window like this;
            ? dtoc(date()) and see what you get.

            If you cannot derive a logical link, then the last option I would go for is the DUMMY field.
            A One char field in both tables and link on that. It doesn't have anything in it, so both tables will be linked completely.
            Ted Giles
            Example Consulting - UK
            .

            sigpichttp://ec12.example-software.com//
            See our site for Alpha Support, Conversion and Upgrade.

            Comment


            • #7
              Re: Data Sets

              If I get this right

              1. You suggest to prepopulate a new field in primary table with the text "SYM" and include this in the linkage. You can
              2. Do this dynamically - on what basis if the link does not yet exist?
              If it is simply based on the first three letters of text of the child table then you could use something like newtypefield=left(childfield,3) as your link expression

              Comment


              • #8
                Re: Data Sets

                Sounds good.
                I have a composite key of several columns.
                So "SYM"+ column2+ column3... in the parent and SymRecType+column2+ column3+... in the child would work?

                Selwyn.

                Comment


                • #9
                  Re: Data Sets

                  Thanks for your detailed explanations.

                  I will try them and let you know.

                  See also my response to Ray below.

                  Regards,

                  Selwyn

                  Comment


                  • #10
                    Re: Data Sets

                    Sure. That expression would establish a link for child records where symRecTyp contains "SYM" AND the field is only 3 char wide AND column2 and column3 match.

                    Comment

                    Working...
                    X