First Informatica software doesn't support TIMESTAMP WITH TIME ZONE at all, so you better change all those attributes to Timestamp anyway.
Second you can do that automatically once you have imported all those tables.
Export them all to a XML file and use some code (may be Perl, Python, Basic, a PowerCenter mapping, Java, C... whatever you like or can handle) to look for those TIMESTAMP attributes with a length of 0; change the length in the XML file to 29,9; then re-import those source/target definitions into the PowerCenter repository.
Granted, that's only an idea, I haven't tried it myself yet. But I do know that quite a few people had to follow similar approaches in order to adapt VARCHAR/VARCHAR2 attributes to appropriate lengths when using Unicode strings.
Exporting all the impacted tables in an XML,finding and replacing all VARCHAR(0) to greater precision VARCHAR column and again re-importing the tables in informatica is basically a manual work.
To avoid manual work, as per your suggestion, we can use some code (may be Perl, Python etc) to look for those TIMESTAMP attributes with a length of 0.
But, we are in search of a better way out where we can use any ODBC parameter for converting TSWTZ column directly to VARCHAR(64) or with greater precision VARCHAR column.
Could you please suggest the smae
Unfortunately I cannot. My suggestion was meant as kind of a "workaround" in case no one else can give a better answer to your question (and I still hope someone will do). Of course it would be better to avoid this scripting work, no question.
Good luck and regards,