Is it possible to lock the DB and add a pending action queue? about dexie.js HOT 7 CLOSED

Yes, IndexedDB transactions are ACID and solves exactly this,

Please read the docs! There are plenty of samples: https://dexie.org/docs/API-Reference#transaction

Think of a transaction as a lock where you lock the given tables so that any other piece of code trying to lock the same tables would block before entering it.

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You can read about database transactions in general: https://en.wikipedia.org/wiki/Database_transaction

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Thanks I will read all of these docs! It sounds great, one last question for now is: you mentioned to use a get and put but is it also OK to use a transaction with get and update? Update makes more sense for this I think because I am only updating one of the column values in the table and not the entire row.

You'd need to get and update the object within a transaction. However, make sure not to query the external API within that transaction. Instead query API first, then do the transaction with a get and a put.

Absolutely, update is also ok - it's just that update will internally do get and put because IndexedDB doesn't have update natively, so if you do a get anyway, it's easier to just manipulate the object as you like and then put the result back. Update would imply another get after your get.

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You'd need to get and update the object within a transaction. However, make sure not to query the external API within that transaction. Instead query API first, then do the transaction with a get and a put.

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Thanks for the response, is there an example of how to properly implement something like this? My specific use-case would be to use Dexie as a local client-side DB for a chat messenger application.

So a there could be messages being sent/received at the same time that need to be added to the DB. When sending a message there will also be multiple status states that will need to be updated on the message record in the DB in real time like failed or success.

So there could be several database read/writes happening all within the same time period if a conversation is happening quickly.

I looked at the Transaction documentation but it wasn't exactly clear to me how that can be used to implement the desired behaviour of not having DB conflicts. Will switching every DB action to a transaction fix this problem even if the actions are happening from many different scopes within the application?

Is this the right page to read to try and understand how Transactions solve this? https://dexie.org/docs/Dexie/Dexie.transaction()

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Thanks I will read all of these docs! It sounds great, one last question for now is: you mentioned to use a get and put but is it also OK to use a transaction with get and update? Update makes more sense for this I think because I am only updating one of the column values in the table and not the entire row.

You'd need to get and update the object within a transaction. However, make sure not to query the external API within that transaction. Instead query API first, then do the transaction with a get and a put.

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Great thanks for the tip, looking forward to implementing these transactions!

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