Delete single entry in tinydb app inventor 2

[Stephen Jones]

I have created a member database for a small club and can add members to the database.

I also need to be able to delete individual members as and when they lapse

I can't work out how to do this.

This was my attempt.

Can anyone help?

[SteveJG]

Your method clears the name from the List.   To clear an individual TinyDB record, you should use the   TinyDB.ClearTag    

                                                                                                                                                                         tag               where the tag puzzle pieces is the record you want to eliminate.

You probably need to do that in addition of removing the member from the List that manages the contents of the TinyDB.  Does that seem right?

Try it and let us know what you discover.

Regards,

Steve

[Stephen Jones]

Thank you for that, would you be able to put an image of the blocks that would be used?

Thanks

Steve

[SteveJG]

A block like this will allow you to delete a single entry provided that each entry is stored as a tag  

Whether clearing a specfic tag is useful depends on how you set up your database.  How you have your organized your database  is not determinable from the image you posted.   If everything about the member is stored in the tag,  BadMember,  you can use the  above block to delete everything associated with BadMember.        If you have separate lists of members etc., what you have to do to remove a member name might be much more complicated.  Perhaps the following will explain:  http://ai2.appinventor.mit.edu/reference/components/storage.html#TinyDB  how the TinyDB works.   How  your records stored in the TinyDB determines exactly what you need to do.

We want you to have fun with App Inventor so here are some resources to help you learn to 

use the AI2 tools  A very good way to learn App Inventor is to read the free Inventor's 

Manual here in the AI2 free online eBook   http://www.appinventor.org/book2 ... the links 

are at the bottom of the Web page.  The book 'teaches' users how to program with AI2 

blocks.

There is a free programming course here 

http://www.appinventor.org/content/CourseInABox/Intro  and the aia files for the projects 

in the book are here:  http://www.appinventor.org/bookFiles  

How to do a lot of basic things with App Inventor are described here:  

http://www.appinventor.org/content/howDoYou/eventHandling  .

The MIT tutorials are here:  http://appinventor.mit.edu/explore/ai2/tutorials.html

Another free course is here:  course for Teachers in the link: 

http://appinventor.mit.edu/explore/teaching-app-creation.html

How the components and AI2 works is described 

• Language Blocks Documentation
• Components Documentation

Regards,

Steve