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
Devcon 2020 Goes Virtual! LEARN MORE >

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

Database compact

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
    #1

    Database compact

    Hi folks,

    It may sound silly but what does DATABASE COMPACT actually physically do ie will it affect any or my data or scripts etc
    I ask because nowhere in the documentation can I find a reference to it.

    Mike
    Tags: None
    #2
    RE: Database compact

    Mike,

    Hardly a silly question. One explanation can be found in the xbasic manual under dictionary.update() which does the same thing as database compact except it is limited to the specified table.

    One thing which does not seem well understood it that the data dictionary for a table is actually a table itself which contains form definitions, table scripts, reports, etc instead of field data. One dictionary file contains "indexes" that links all of this information. For instance, this keeps the correct script with a form. Just like a table that is full of deleted data has a lot of "junk" left over taking up space, the data dictionaries can contain many entries that are now not being used. Some of the linking "indexes" can get corrupted, just like a regular table index sometimes needs fixed. Compact removes these entries, reduces the size of the data dictionary files, and reduces the possibility for errors. It also will reindex each table.

    Recently I got a graphic demonstration about how important keeping all of these files cleaned up can be. I copied just an updated .ddd file to a different copy of a test app. I missed the .ddm and .ddx files. When I went to open a form, I got the wrong form. Another form could not be found. It wasn't that they weren't there, there just was no link to link them to the correct names and references.

    The best advice is to compact regularly during the design process and keep the dictionaries as clean as possible. I recently looked a app designed by someone else and saw that the data dictionary files for one table were huge. Compacting them reduced their size to about 1/5 of the original size. No wonder the user had screwed up references.

    Jerry

    Comment

      #3
      RE: Database compact

      Dictionary.update()
      Syntax:
      Dictionary.update( Data Dictionary Filename)
      Description:
      Performs maintenance on the specified Data Dictionary Filename, making the
      data dictionary more compact and efficient. You can use this function with table
      (*.DDD), or set (*.SET) dictionaries.
      As layouts and layout objects are added and removed, the data dictionary size
      will increase. Perform maintenance to reduce the size of the data dictionary. This
      method is identical to the �Database compact� command on the �File� menu,
      except that it allows you to perform maintenance on individual dictionaries,
      whereas the �Database compact� command performs maintenance on all
      dictionaries in the database.
      There can be only one.

      Comment

        #4
        RE: Database compact

        Thanks guys for you informative help.

        You know this could be the exact same reason why I have been having some weird problems lately.

        Mike

        Comment

          #5
          RE: Database compact

          I had a similar problem...forgetting or neglecting to perform this maintenance. Solved it by adding a Database Compact script to the App Exit button just before A5.close(). Now, every time the app closes, a Database Compact is performed.

          Comment

            #6
            Beware of "compact"

            Compact can also delete items such as field rules. I have a fairly big program that has about 50 databases. Database compact will not work at all. It always comes back as "cannot update...". In addition, if I compact 1 of my databases, all field rules, reports, etc are deleted. BIG PAIN. There has never been any explanation or solution to my problem of why capact does not work. If things look really strange after you compact, compacting may have caused the problem in the first place. It took my a while to finally figure out that compacting was the reason I was losing things all the time.

            Mick

            Comment

              #7
              RE: Beware of

              Mick,

              One thing which might effect what you are seeing was posted on the board some time ago from selwyn. If an expression won't calculate in an index, the index is deleted. It is my understanding that the same can occur in a field rule expression. If compact is deleting field rules and other information, this could be a very good indication that the data dictionary is badly corrupted. As I posted in an earlier message, if a link between a form and the table is lost, for instance, the form will appear deleted even though it really still exists. On that one table, I would try duplicating the table without data and try to compact the new table alone. If it works, you could then copy the data dictionary back over the original files. Of course, backup everything first. The only time compact caused problems for me was when I knew the data dictionary was badly corrupted. In that case I had to reconstruct the table from scratch, build new indexes, and cut and paste all of the forms, browses, etc to the new table.

              Another issue is the "cannot update" message. You will get this message if a table is open when you try to compact it. I run a compact operation from a menu that is specifically excluded in the code as it is based on a table with one record, no field rules, or indexes.

              Jerry

              Comment

              Previous template Next
              Working...
              X