Report Output is not same as R/3 4.7 and ECC6 ( sort issue)

Question

Dear Experts,
I have a problem with external sort used in the program. due to that report output records are not in the same order.
For example, i am extracting data from BSEG with fields company code, fiscal year, document no, item no, amount and GL Respectively.
in both the systems (R/3 4.7 and ECC6), data in internal tables are in same order by default.
but after the external sort using filelds company code, fiscal year and document no.
output records are sorted exactly with respect to the external sort order in both systems, but for certain line items are not in same order.
Please check below example.
For example in R/3:
684
2012
5000000532
5
H
2662.51
411100
684
2012
5000000532
4
H
13
555200
684
2012
5000000532
3
S
0.5
635400
684
2012
5000000532
2
S
12.5
627800
684
2012
5000000532
1
S
2662.51
555209
In ECC6,
684
2012
5000000532
1
S
2662.51
555209
684
2012
5000000532
2
S
12.5
627800
684
2012
5000000532
3
S
0.5
635400
684
2012
5000000532
4
H
13
555200
684
2012
5000000532
5
H
2662.51
411100

Answer 1

The order of extracted records can no be assumed to be constant, any SQL optimizer can change behavior, even without any wide upgrade, but a single database or kernel patch as well as many operation of database administrator can change the order, as well as a change of user behavior, if they fill now another field in selection. So it is good practices to always sort (or use sorted type) internal table extracted or use a ORDER BY clause (provided there is an index in database, else do not)
Read online documentation of SELECT statement clause ORDER BY
The order of the rows in the result set refers to all columns that are not listed after ORDER BY, is undefined, and can be different in repeated executions of the same SELECT statement.
There are also some [MANY > 1000] OSS notes on the subject (look for your database, e.g.  1858427 - Incorrect Sorting of SQL-Select Statement, 1859655 - The result set of an SQL-Select Statement may not be sorted, 1858479 - Result set of select statement is not sorted, 1858569 - Incorrect access to result set of SELECT statement, etc.)
Also if you sort an internal table and require records with same key values to keep their respective order, use the STABLE clause.
Regards,
Raymond