Temp tables using an interfaces in ci

Question

what is the purpose of temp tables in ci while performing interfaces
any one explain me processing

Answer 1

Processing a CI messes up SQL cursors I recently discovered. A temp table or a rowset to retrieve the values you're looping over (if applicable of course) can help resolve this issue.
If you mean App Engine processing in general (as in post above), it mostly is to avoid looping per row and doing the same action over and over again, or to avoid having to put a lot of large tables into 1 query (you could update some of the fields in different steps), for instance support I want to update an amount for each person, then I could have a
In most cases less performant version:
DoSelect:
%Select(EMPLID)
SELECT EMPLID FROM your query
Followed by:
INSERT INTO My_Result
SELECT * FROM My_Table
Where emplid = %Bind(Emplid)
In most case better:
SQL step:
Insert into %Table(My_ExmplTMP) (EMPLID) SELECT EMPLID FROM your query
Followed by:
INSERT INTO My_Result
SELECT * FROM My_Table Tbl, %Table(My_ExmplTMP) Tmp
Where Tbl.emplid = TMP.Emplid