A common practice is to use a single letter, the first letter of the type, c
for customers
, p
for products
. x
is used a lot, I use x
when I am typing out the lambda but will usually refactor into a descriptive name or single letter that matches the collection item.
If it is more than a simple lambda, consider using a proper descriptive variable name as always.
The end goal is to make the code readable. If you feel a simple x
is readable, use x
. If you feel giving a full name more readable use a full name.