Difference between LSMW and CATT

Question

Hi all,
Can anybody tell me the difference between LSMW and CATT?

Answer 1

CATT
SAP users use CATT frequently to upload master data or to
make changes to master data records. SAP Consultants and
Abapers tend to use it for creating test data. The
transactions run without user interaction. You can check
system messages and test database changes. All tests are
logged. The CATT records your keystrokes while performing
the actual transaction. You then identify the fields that
you wish to change in that view. Then export this data to a
spreadsheet to populate with the data required. This is
uploaded and executed saving you keying in the data
manually.
To perform CATT, it has to be enabled in your production
environment (your systems administrator should be able to
do this - SCC4). You will also need access to your
development system to create the CATT script.
The process of uploading data with a CATT:
Activate CATT in your client
In transaction code SCC4 - click the change button
Double click on the client number
In the Restriction section, tick Allows CATT processes to
be started.
Upload data using CATT
1. Create Import variant for the fields you need
Transaction SCAT
Goto Parameters
Create Import Variant
Goto Variant -> Edit
Goto Variant -> Fast entry or F9
Duplicate 01
2. To change the MRP Group for a list of Material
Assuming that I want to change the MRP Group for a list of
Material.
My text files should look something like this:
[Variant ID] [Variant Text] &ZDISGR &ZMATNR
--> Parameter texts MRP group Material
--> Default Values M1 A001
Changes to the default values displayed above not
effective
#01  M1 A001
#02  ''     A002
#03  M1 A003
Note : '' denotes a blank in the field. e.g. Material A002
MRP group will be replaced by a blank.
3. Configure the recorded entry fields to read from the
imported text file data
In the CATT : Maintain functions test case Screen
Double click on the Object Name
Double click on the screen number with your desired fields
Park the cursor on the fields
Click Edit -> Details
Fill in the Parameters Name and Field Contents
Finish Save it.
Assign your text file data.
In the CATT : Execute test case Screen
Click External from file and choose your text file
CATT will now read from your text file and update whatever
data you have specified.
LSMW
Using LSMW you can update any kind of data but no changes to database are allowed, where as CATT tool can update only master data, which also allows changes to the master data and also a significant testing of data is possible. LSMW is a tool that offers you 4 ways to import data into SAP, they are BDC, Direct Input, BAPI(BO), IDOC.It is used for migrating the data b/w the Non-SAP and SAP application to do for that we can take the Non-SAP application data and Converts the data into the Legacy data. After the Legacy data creation convert the data in to the "Flat file". That flat file is in the form of text file or excel format.If the file is in the form of text format
we can create the ".txt" file ("ABC.txt")and in the form of
excel ".xls" file is created. flat file for dos and .xls
file for IBM. The converted file (.txt/.xls)is either upload or download. The Upload functionality if used for .txt file to SAP and where as Downloading is the concept while SAP to .txt/.xls file.
Execute the transaction LSMW to start transfer of data,Before using the LSMW we should have good knowledge about the business object and the fields that will be transferred.
There are 14 steps that are normally used and these are :
1)   Maintain Object Attributes.
2)   Maintain Source Structures.
3)   Maintain Source Fields.
4)   Maintain Structure Relations
5)   Maintain Field Mapping and conversion rules .
6)   Maintain Fixed Values,translations ,user defined routines.
7)   Specify Files .
8)   Assign Files .
9)   Read DATA.
10) Display Read Data.
11) Convert Data.
12) Display Converted Data.
13) Create Batch Input Session.
14) Run Batch Input Sesion.