Is keeping a transaction open considered a bad practice?

Question

I keep the database variable in the window scope, but now I'm starting to wonder about the transaction and object store as well.

myRequest = indexedDB.open('myDatabase')
myRequest.onupgradeneeded = function(response) {
 var myDatabase
  ,myObjectStore
 
 myDatabase = response.target.result
 myObjectStore = myDatabase.createObjectStore('myData',{autoIncrement:true})
}
myRequest.onerror = function(response) {
 debugger
}
myRequest.onsuccess = function(response) {
 var obj = {}
 window.myDatabase = response.target.result // This is ok, right?
 window.myTransaction = myDatabase.transaction(['myData'],'readwrite') // But what about this?
 window.myObjectStore = myTransaction.objectStore('myData') // And this?
 obj.field1 = 'a'
 obj.field2 = 'b'
 myObjectStore.add(obj)
}

It probably doesn't make sense to keep the transaction in the window scope, to be used whenever you want to refer to a particular 'table'.

After all, when would the transaction be considered oncomplete? I just thought about this instead of creating a new transaction every time I needed something.

Answer 1

I do not suggest keeping a reference to a transaction outside of the scope that it is used. I do not suggest keeping a reference to the database connection outside of the scope that it is used. And I do not suggest keeping a reference to an object store outside of the scope it is used.

There is very little performance benefit to keeping such references. There is not much of a readability benefit to keeping such references. There is a large risk of encountering bugs when keeping such references.

I would strongly suggest you create a new database connection each time you need it, create a new transaction each time you need it, and create new object store references each time you need them. These should be short lived objects that are garbage collectable.