mid and index chart function

[Applicable88]

Hello,

i have a script load here. 

Its referring to a column of  called "failure descriptions".

it can be a words like: 'bicycle repair', 'wheel air malfunctions..... but there are also values like serialnumbers which interest me the most (9999)1234, (9999)4321......and so fourth

like so:

Failure Description

wheel air

(9999)4324

(9999)4555

Now I see in the load script there is something like this:

mid([Failure Description],Index([Failure Description],')')+1 as ShelfID

Can someone telle me what it does? A Index function in a mid function? But what does that do with my data.

Thanks in advance!

[Taoufiq_Zarra · Accepted solution]

@Applicable88 

below a table with the initial value and the result of the mid ...

the goal is to extract the string that comes just after the ')' ( so the use of the Index function).

if you notice we made a left joint before, to keep only ShelfID  that exist in Table 1.