Alpha Software Mobile Development Tools:   Alpha Anywhere    |   Alpha TransForm subscribe to our YouTube Channel  Follow Us on LinkedIn  Follow Us on Twitter  Follow Us on Facebook

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

Calculated Fields in MySQL

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

    Calculated Fields in MySQL

    So I've been working at converting from DBF to MySQL. So far so good. One of my last final hurdles is re-creating what in DBF is a "calculated field expression" in the field rules. Trying to determine the best equivalant method in MySQL. I searched on the message board and MySQL and have not found the best route or details to solving this issue, which seems very straight forward.

    Here is my simple challenge. I have a MySQL table called 'load' and 4 fields 'TTL', 'BRK_PAY', 'BRKQTE_PRC', 'BRKQTE_COM'. My expression would look like:
    BRKQTE_COM=(TTL-BRK_PAY)*BRKQTE_PRC
    Logic tells me, although I'm new to much of this, this should be constructed in MySQL. By the way I use Navicat to admin my tables etc. However, creating a server-side event in Alpha might be the way to go as well. So my questions are as follows. Please answer as many as you know or feel comfortable with answering.

    1. Should this be created in Navicat(MySQL)? Perhaps as a trigger or some other method I'm not yet familiar with?
    2. As a server-side event in Alpha?
    3. The basic code required in order to write the trigger or server-side event.

    Finally, perhaps this isn't for the forum for this, but I'm interested in working with someone proficient with MySQL/Navicat/Alpha V11 web applications. By "working with" I mean paying.

    Travis

    #2
    Re: Calculated Fields in MySQL

    I think adding (TTL-BRK_PAY)*BRKQTE_PRC as BRKQTE_COM to your select statement will give you the column you want.
    Gregg
    https://paiza.io is a great site to test and share sql code

    Comment


      #3
      Re: Calculated Fields in MySQL

      Search Google for MySQL user variables, you will find plenty of examples. I got the one below from a site to get a row number;

      Code:
      SELECT @row := @row + 1 as row, id, product_class, category, picture 
      FROM product, (SELECT @row := 0) r
      Juan Silva
      My Small Bizz, LLC
      sigpic

      Comment


        #4
        Re: Calculated Fields in MySQL

        Thank you, where do I enter this select statement? I'm sure the lightbulb will go off for me very soon. But it's all just so new for me. My hope is in Navicate, but if its somewhere else and it works that is fine too.

        Comment


          #5
          Re: Calculated Fields in MySQL

          You must use a grid to be able to use an SQL statement, easily anyways. On a dialog I do not know how you would do that unless you took complete control of the whole IO using xbasic. But on the grid simply select on the query page that you want to use an SQL statement instead of a table.
          Juan Silva
          My Small Bizz, LLC
          sigpic

          Comment


            #6
            Re: Calculated Fields in MySQL

            Thank you guys... Ok, I'll will start to experiment with the SQL Select Statement vs the table or view option. Juan, for what its worth. I don't have the problem with client-side calculations saving in the MySQL table from a dialog.

            Comment


              #7
              Re: Calculated Fields in MySQL

              Travis,

              I "assumed" you were working with a grid.
              Still based on that thought, I think the pic below might help.

              Gregg
              Gregg
              https://paiza.io is a great site to test and share sql code

              Comment


                #8
                Re: Calculated Fields in MySQL

                Yes Gregg, you assumed correctly. In fact, I was fumbling around right in the area of your pic, thank you! I got my expression to work, but it's creating its own field name 'expr1'. I tried changing the alias to the actual field name 'BRKQTE_COM' but it is still not updating the value on the server. I noticed it has no Table assigment, but I can't change it either. I can see I'm very close, but not quite there.calculated_field.png

                Comment


                  #9
                  Re: Calculated Fields in MySQL

                  I think we have a few issues here.

                  I thought brkqte_com was a calculated column from your project with the dbf table.
                  The code I gave was to display the information, not to write anything to the server.

                  With what I'm seeing now, and I get a bit fuzzy (i'm learning sql too),
                  you need an update statement that resembles : update load set brkqte_com = (TTL-BRK_PAY)*BRKQTE_PRC where {recordid} = {something unique}

                  Hope this gets you a bit closer.
                  Gregg
                  https://paiza.io is a great site to test and share sql code

                  Comment


                    #10
                    Re: Calculated Fields in MySQL

                    Originally posted by tsyeti View Post
                    Yes Gregg, you assumed correctly. In fact, I was fumbling around right in the area of your pic, thank you! I got my expression to work, but it's creating its own field name 'expr1'. I tried changing the alias to the actual field name 'BRKQTE_COM' but it is still not updating the value on the server. I noticed it has no Table assigment, but I can't change it either. I can see I'm very close, but not quite there.[ATTACH=CONFIG]33311[/ATTACH]
                    BRKQTE_COM is a field in your table, yes?

                    You could add a trigger in MySQL to do the calculation there --- if this is something that needs to be current & up-to-date always, this may be the best place to do it. Then you don't need to worry about keeping it in sync via Alpha 5.

                    Code:
                    *** note: I don't know if you need to include "new." before TTL, BRK_PAY, and BRKQTE_PRC here... ***
                    
                    CREATE TRIGGER unique_name_of_trigger1
                    BEFORE INSERT ON load
                    FOR EACH ROW
                    SET new.BRKQTE_COM = ((TTL - BRK_PAY) * BRKQTE_PRC);
                    
                    CREATE TRIGGER unique_name_of_trigger2
                    BEFORE UPDATE ON load
                    FOR EACH ROW
                    SET new.BRKQTE_COM = ((TTL - BRK_PAY) * BRKQTE_PRC);
                    Alternatively, you can add code to update the field whenever TTL, BRK_PAY, or BRKQTE_PRC change in the grid in their respective onChange events. Your select statement then simplifies to "SELECT TTL, BRK_PAY, BRKQTE_PRC, BRKQTE_COM FROM load".

                    Or keep the calculated field and whenever that changes, save it to BRKQTE_COM manually.
                    Alpha Anywhere latest pre-release

                    Comment


                      #11
                      Re: Calculated Fields in MySQL

                      Thank you all for your assistance. I've made progress on creating a trigger to calcuate the formula mentioned above, but I'm still having difficulty with the update. I'm going to start a new thread a bit more specific.

                      Comment

                      Working...
                      X