Hi Rajasekhar,
Great question. It depends on your requirements. The inflight method is used when you are NOT allowed to EVER store ANY PII information on ANY hard drive space. Please refer to this documentation for use and examples:
Fast Data Masker and Transformation Maps
The limitations are plainly called out in the documentation for the types of databases AND the functions supported. Please note that it is very difficult to write an In Flight masking therefore all the masking options that are available for In Place masking are not supported with In Flight Masking.
If you are allowed to have PII information on a hard drive, then you use the In Place masking. The following documentation and examples are found here"
Data Generation Functions and Parameters
Please note the breadth and depth of the masking as well as the examples with the individual functions.
Please let us know if this answers your question.
Cheers!
Les