when calling UPDATE from the result set of a SELECT statement, is the order in which rows from the SELECT statement 100% geronteed?

SQL Apprentice Question
when calling UPDATE from the result set of a SELECT statement, is the order
in which rows from the SELECT statement 100% geronteed?

tableA


myid
-----------
0
1
2
3
4
5


UPDATE tableB u
SET myid = i.myid
FROM tableA i
ORDER BY myid


Will this always update tableB with 5 since it is the last one? is this 100%
garonteed to follow the order of the source result set?


Celko Answers
No. There is no ordering in a table by defintion. Since this strictly
proprietary syntax it an do anything MS feels like next week. You are
just looking for the comfort of a 1960's sequential file system
instead of learning to think in RDBMS.


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