# Memento DB: better than a notebook

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#### Budro0

##### Well-Known Member
In a couple previous threads (here and here), the idea of creating a rocket flight log app had been kicked around and at least @neil_w had some success in getting a working product. But as he noted, Airtable required a data connection to work. For 80% of my flights, that would have been fine. Those couple other times made me really want something that synced with an online database, but the info could still reside on my phone.

I have used Memento DB for a while but it wasn't much more than a glorified note taking app (the way I was using it). Neil's post really got me thinking and researching if I could do what I want with Memento and also provide something that might be useful to the community. It's not much, but what follows is what I was able to piece together the past couple days.

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#### Budro0

##### Well-Known Member
I started with a table called Rockets, which was already built as a note card on the rocket. I tweaked it a bit to account for how I was now going to build this living document.

Below is one example. The motors listed are linked from another table (motors) and are selectable as you see fit. You will notice there are two motor sections - this is an odd nuance to Memento. One is text only, the other is essentially a link to the actual motor entry in the the other table. I'll discuss some other nuance in a subsequent post.

The rocket table is fairly straight forward and gives some critical basic stats (motors, dimensions, etc) as well as being the entry point for flight logs, data, pictures and notes. There are fields that are not shown in this view as I do not have them filled out yet.

#### Budro0

##### Well-Known Member
On to motors. This is where some of that nuance comes in. As you will see, I used the motor entries to hold sim data for the rockets. As you may have noted above, for that rocket the G74 has a weird .2 tacked on. I have two rockets that like the G74 and so I opted to make separate entries for each motor. Another option would be to create another table of just sim data which links discrete rockets and motors and shows sim data. That is definitely an option I am going to look into.

This table is fairly self explanatory. I was able to do some calculations on this, so the stability is dynamic. If you change your CG on the field, you can plug the new measurements in and it will spit out a fairly accurate stability margin for you.

#### Budro0

##### Well-Known Member
The last two tables are flights and fields. Both are fairly simple and provide a bit of detail, but more could definitely be added (I've kicked around trying to figure out how to pull weather info).

An entry in the flights table does not appear to have much info. This is a note-taking table - when you click edit on an entry, you get date, rocket, field, motor, notes, files, pictures, etc. The fields that make sense to be linked are, and otherwise it's a fairly versatile format to log a flight.

The fields table is more straight forward. Location, imagery, and restrictions are all set up. I also just realized this would be a great spot to save flight cards and waivers. So those will be added in the next edition.

#### Budro0

##### Well-Known Member
Honestly, this wasn't that hard to piece together, it just took some time and brain power to figure out what all I want to have in there. I know this won't work for everyone, but if you are interested, please steal my work and make it your own. I'd like to know what you changed and how it works better for you.

I supposedly uploaded all my DB templates to Memento (http://libs.mobi/t/4828057769607168). You can also search for "Budro Model Rockets" in their template library.

As a final note, I did pay to upgrade to pro - I do not think that is necessary to use the templates I've built. I only did it to get more functionality on the computer. It should work fine as a free app for you on the phone and PC.

#### neil_w

##### Good at some things
TRF Supporter
Good stuff.

I looked up Memento DB and unfortunately it doesn't support iOS, so it's not an option for me. Mobi DB is next for me to try.

After you planted the idea in my head I played with putting sim data into my own DB. I started with a separate table of sim data results:

That worked fine but ultimately I decided that the extra DB functionality of having this data in a table wasn't really buying me anything, and it was consuming a lot of records, which are a precious resource in the free version of Airtable. So I eventually switched to just entering it into a big old text field in the rockets table, e.g.:

For each motor, the three following numbers are rod speed, altitude, and ideal delay. That is sufficient for me to make informed decisions about what to do at a launch. I don't think I'm giving anything up by doing it this way, and it's really easy to see at a glance.

#### Greg Furtman

##### Well-Known Member
TRF Supporter
I supposedly uploaded all my DB templates to Memento (http://libs.mobi/t/4828057769607168). You can also search for "Budro Model Rockets" in their template library.
@Budro0 I installed the free desktop version and searched for your Budro Model Rockets DB, found it & downloaded it. It is 0 bytes in size. Looks like the upload from your phone didn't work.

#### Budro0

##### Well-Known Member
@Budro0 I installed the free desktop version and searched for your Budro Model Rockets DB, found it & downloaded it. It is 0 bytes in size. Looks like the upload from your phone didn't work.
Interesting... I've never claimed to smart on this... I will reupload from another device. I will say that I only uploaded the template, no data, and maybe it appears to be 0b until you add an entry?

#### Greg Furtman

##### Well-Known Member
TRF Supporter
Interesting... I've never claimed to smart on this... I will reupload from another device. I will say that I only uploaded the template, no data, and maybe it appears to be 0b until you add an entry?
@Budro0 I didn't see any tables or structure. Even without data the template structure should be at least a few KB.

#### neil_w

##### Good at some things
TRF Supporter
There's one Airtable function that I haven't been able to replicate yet with MobiDb on the iPhone; I'm wondering if Memento Db does it for you.

In my Flights table, there is a field to link back to a rocket, e.g.:

If I then go back to the rocket, there is (automatically created) a field that links back to the flights:

In the table view, that's only mildly useful, but if I expand that item I get the real list (never mind the janky formatting, I'm experimenting):

Now *that's* more useful. In the expanded item view, I automatically see lists of all items linked back from other tables.

The funny thing is: in Airtable, I cannot prevent this from happening. Whenever there is a link, it goes in both directions and shows in both places. By contrast, in Mobi Db, I can't make this happen at all (at least, I've not figured it out yet). If I want to see all Diamond Cutter flights, I need to go to the flights table and group by name or sort by name or whatever. That's not a disaster, but it's definitely not as nice.

Will Memento Db do this for you, and if so how do you set it up? Maybe it'll give me a hint of how to do it here in Mobi.

#### Greg Furtman

##### Well-Known Member
TRF Supporter
@Budro0 I installed MomentoDB on my Pixel 4a and I can see your fields on my phone. But not from my laptop. I wonder what's going on?

#### Budro0

##### Well-Known Member
@Budro0 I installed MomentoDB on my Pixel 4a and I can see your fields on my phone. But not from my laptop. I wonder what's going on?
So I struggled with this on my laptop too. I'd add an entry and even still it would be blank. There is an option on the phone app to set the default items to show in list and table views. I can take screenshots if you need but from the "my libraries" screen, select the 3 dots on a library and "edit." On the top left of the next screen, select "main" and then ensure there are options checked under "entry name." That should fix any visibility issues with your entries. You'll want to check that on every library you have.

I also re-uploaded the 4 libraries as separate entities in the catalog (labeled as v2). I hope those can help sort out the issues.

#### Budro0

##### Well-Known Member
There's one Airtable function that I haven't been able to replicate yet with MobiDb on the iPhone; I'm wondering if Memento Db does it for you.

In my Flights table, there is a field to link back to a rocket, e.g.:
View attachment 456231
If I then go back to the rocket, there is (automatically created) a field that links back to the flights:
View attachment 456232
In the table view, that's only mildly useful, but if I expand that item I get the real list (never mind the janky formatting, I'm experimenting):
View attachment 456233
Now *that's* more useful. In the expanded item view, I automatically see lists of all items linked back from other tables.

The funny thing is: in Airtable, I cannot prevent this from happening. Whenever there is a link, it goes in both directions and shows in both places. By contrast, in Mobi Db, I can't make this happen at all (at least, I've not figured it out yet). If I want to see all Diamond Cutter flights, I need to go to the flights table and group by name or sort by name or whatever. That's not a disaster, but it's definitely not as nice.

Will Memento Db do this for you, and if so how do you set it up? Maybe it'll give me a hint of how to do it here in Mobi.
So it does do that, but it was automatic as well. The link back opens separate cards in your current view though, so a little different than what you've got, but that same concept. I originally thought it obnoxious, but there is a real utility in it.

Having not played with Mobi, I'd think a link to entry to add rocket to flight, and then in your rocket entry have a field that is conditionally filled with flights that the rocket is linked to.

#### Budro0

##### Well-Known Member
Just a quick update as my month of "Pro" expired on Memento. I was able to use the DB at a couple launches and I found some changes I'd like to make. Notably, I do not like how I built the sim data into the Motors table and I am going to split that out into it's own table and rewicker the Motors to just be motor data (impulse, burn time, etc). Adding flights, altimeter data, pictures, even video was fairly seamless and I am a huge fan of how it all worked on the field.

Now the critical component - as a basic user again, I can no longer edit more than my first three tables on the computer and phone. Meaning I can no longer add flights among others. I think for about $3 per month, I get that back, but I'm super cheap. So I will be switching gears - looking for a truly free option that works offline with both my phone and computer. #### neil_w ##### Good at some things TRF Supporter Just a quick update as my month of "Pro" expired on Memento. I was able to use the DB at a couple launches and I found some changes I'd like to make. Notably, I do not like how I built the sim data into the Motors table and I am going to split that out into it's own table and rewicker the Motors to just be motor data (impulse, burn time, etc). Adding flights, altimeter data, pictures, even video was fairly seamless and I am a huge fan of how it all worked on the field. Now the critical component - as a basic user again, I can no longer edit more than my first three tables on the computer and phone. Meaning I can no longer add flights among others. I think for about$3 per month, I get that back, but I'm super cheap. So I will be switching gears - looking for a truly free option that works offline with both my phone and computer.
Well, you can try MobiDB, which supports iOS, Android, and Windows. It has a couple of limitations that for the moment keep me using Airtable, but it's pretty good, and worth a look.

#### Budro0

##### Well-Known Member
Well, you can try MobiDB, which supports iOS, Android, and Windows. It has a couple of limitations that for the moment keep me using Airtable, but it's pretty good, and worth a look.
I just downloaded a handful (including MobiDB) to see how they work. I think I saw it had an annual subscription of $10 for full functionality - which is just about the right price... More to follow as I put them through their paces. #### BEC ##### Well-Known Member I will be interested to see where this goes. I am still logging in a 4x6 notebook (just started another one a few days ago). I'm also curious if we've crossed paths at 60 Acres....I was there on the afternoon of St. Patrick's Day doing some FlightSketch firmware 29 vs Adrel data comparison flights. #### neil_w ##### Good at some things TRF Supporter I will be interested to see where this goes. I am still logging in a 4x6 notebook (just started another one a few days ago). I was going to suggest that if you have internet access at your field, then my Airtable app would work great for you. Then I remembered how many flights you're putting in a year... you'd bump into the 1200 record limit (on the free account) way too early. #### Budro0 ##### Well-Known Member I will be interested to see where this goes. I am still logging in a 4x6 notebook (just started another one a few days ago). I'm also curious if we've crossed paths at 60 Acres....I was there on the afternoon of St. Patrick's Day doing some FlightSketch firmware 29 vs Adrel data comparison flights. Now that I see your sig line, yes we have. I am the ruggedly good-looking gentleman with the smokeshow of a wife.... I think I was right in front of you at the 27 March launch. #### Budro0 ##### Well-Known Member Last night I got to playing around with several different database apps: MobiDB, Easy Database, Binders, and PortoDB. What I was looking for is something that could easily import my Memento data and replicate the relationships. Nice to have is the ability to work on a PC for data entry, and of course free apps get bonus points. None of them really checked all the boxes. MobiDB and PortoDB are the closest, but both have the same annoying shortfall. When you link table data to a field, you can only select one related field. As an example, I have a motors table and link that to rockets. In order for me to link three motors to one rocket, I have to build three linked fields in the rockets table. With Memento, you could make that one linked field a single or multiple choice option and link all the motors you want to a rocket. So as I was passing out last night, I got back into Memento to look at what a subscription would actually cost me (alot). Then I noticed they have a License Key option for$15. I shot a quick email to their support and just got a note back saying it is a one-time/lifetime purchase, but it is only for the Android app. So there is no cloud sync with PC and I assume my desktop version will be limited to the basic account (3 libraries).

But I still think this might be the way to go, as I have most of the structure built and inputting data is not really the hard part on a phone. Also, I think I can run Android apps on my computer with Windows "Your Phone" app - it may all work out in the end.

If I can ask a favor of anyone that stumbles upon this, could you verify that your Windows 10 PC can run Memento from your Android 11 phone? As may have been noted previously, I'm a tiny bit frgual and am still rocking the original Pixel - with only Android 10....

#### neil_w

##### Good at some things
TRF Supporter
None of them really checked all the boxes. MobiDB and PortoDB are the closest, but both have the same annoying shortfall. When you link table data to a field, you can only select one related field. As an example, I have a motors table and link that to rockets. In order for me to link three motors to one rocket, I have to build three linked fields in the rockets table. With Memento, you could make that one linked field a single or multiple choice option and link all the motors you want to a rocket.
This is sort of the issue that has kept me from using MobiDB. I can link several flights (or motors, or whatever) back to the same rocket... but there is no way to show that list from the rocket. I can go to the list of flights and sort or group by rocket, and that'll ultimately get me the same info, but I want to be able to see it from the Rocket.

Airtable does this automatically; creating from flight -> rocket also creates a link from rocket -> flight, and they can be one to many or many to one.

I asked the dev, and he said it sounded interesting, but clearly was not (yet?) on the todo list.