when you need to reconcile users and have match rule which change target system attribute value for matching you can use 'tokenize' .

For example, i have target system who has value in the match attribute containing logic where first part is unique identifier and rest are other information not required and all separated by "_" , i can use tokenize to pull the first part which is my identifier key to match the IDM attribute which hold same value

example: target match attribute has following value where '1111' is my IDM unique identifier attribute


the setup will be:

Delimiters: '_'

Token number: 1  (this will pull first word in list)

Space Delimiter = FALSE (not required)