Re: db.Listproperty: letters "a" and "L" for strings and ints

[Julie]

The L indicates that the number is stored as a Long (64 bit) integer, and indicates the largest values that can be stored in an IntegerProperty. In this case any positive or negative integer in the range 9.2 x 10^18

The u indicates that the string is Unicode, meaning that it supports all international and extended characters.

The data store viewer displays the L and U so that you can see which data type is being used to store the data. In the cse of the AppEngine database, integer values are automatically converted to and stored as Long, and strings are converted to and stored as Unicode strings. See  https://developers.google.com/appengine/docs/python/datastore/typesandpropertyclasses 

The reason that it is important to know what type of integer or string has been used, is because they can limit what can be stored. For example a non-Unicode string is not able to store a string containing multiple languages.

When your program uses values from the database, just the values are used. The U and L are displayed in the data viewer for your information.


On Tuesday, September 11, 2012 4:21:19 AM UTC+10, namttor wrote:

Newbie question: when making lists in the database (e.g., db.Listproperty(int)), additional letters appear next to the items in the list when I am using the data store viewer. For example:

the list of ints [9, 8, 7] appears as [9L, 8L, 7L]

the list of strings ["a", "b", "c"] appears as [u"a", u"b", u"c"]

but the list of bools [True, False] appears as I expected

Can anyone tell me what these "L" and "u" letters are and if there is any way to get rid of them? I'm sure that there is some resource but for some reason I couldn't find anything how I was searching.

Thanks so much!