2-Way Sync: No Unique ID

How to setup 2-way sync within the same workbook without any unique ID.
Important notes:
* This is the least efficient of the 3 methods, so I would suggest against it unless absolutely necessary

Sheet (Make a copy from the File menu)

Script:
function onEdit(e){
if (!e) throw "Do not run manually";

syncNoID(e);
}

function syncNoID(e){

for (let i in dbData){
if (dbData[i].toString() === id){
return;
}
}
}

Connect with me:
• Twitter @FarrisSpencer

[hydronicrocker]

I wish this was native in sheets, as an option, but thank you so much Spencer - you have saved me entering back into the world of Notion!

[rmtgbesds]

Yes! Thank you, again. Great script, elegant and efficient.

[abdullahquhtani]

Very smart solution form a smart man👍🏼.
Is there any limitation if the same field being edited in the same time? 🤔

[yealovinitall]

Is there anyway to create a new line in for example the "Mary" tab and have it sync with the Database tab, or can new rows only be created in the database tab?

[mepa]

Thanks so much for this tutorial. What's going to happen when I later rearrange the rows/columns (e.g. sort the sheet a-z for various purposes) - will that ruin the formula?

[jaysonouellette]

Hi Spencer, when i change the name of John to Mary in the filter it make all data disapear in the sheet i work in. Any idea why this is happening ? i want to that to filter other data Thanks

[nssdesigns]

Can you post the script where we can use different worksheets?
let db =