Sort stability: Difference between revisions

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 =={{header|OpenEdge/Progress}}==
+The results can be forced to stable by ''additionally'' sorting on the ROWID of the record. If you leave the additional sort out the indexes on the temp-table can influence the result.
-{{incorrect|OpenEdge/Progress|This is not enough as a particular sort might give a particular result whilst saying nothing about the stability '''in general'''.}}
-The results are stable.
 <lang progress>DEFINE TEMP-TABLE tt
    FIELD country  AS CHAR FORMAT 'x(2)'
    FIELD city     AS CHAR FORMAT 'x(16)'
    .
+DEFINE VARIABLE cc AS CHARACTER EXTENT 2.
 CREATE tt. ASSIGN tt.country = 'UK' tt.city = 'London'.
@@ Line 342: / Line 343: @@
 CREATE tt. ASSIGN tt.country = 'UK' tt.city = 'Birmingham'.
+cc[1] = 'by country~n~n'.
-FOR EACH tt BY tt.country:
-   DISPLAY tt.country tt.city.
+FOR EACH tt BY tt.country BY ROWID( tt ):
+   cc[1] = cc[1] + tt.country + '~t' + tt.city + '~n'.
 END.
+cc[2] = 'by city~n~n'.
-FOR EACH tt BY tt.city:
-   DISPLAY tt.country tt.city.
+FOR EACH tt BY tt.city BY ROWID( tt ):
+   cc[2] = cc[2] + tt.country + '~t' + tt.city + '~n'.
-END.</lang>
+END.
+MESSAGE
+   cc[1] SKIP(1) cc[2]
+VIEW-AS ALERT-BOX.</lang>
+'''Output:'''
+<pre>---------------------------
+Message
+---------------------------
+by country
+UK	London
+UK	Birmingham
+US	New York
+US	Birmingham
+by city
+US	Birmingham
+UK	Birmingham
+UK	London
+US	New York
+---------------------------
+OK
+---------------------------</pre>
 =={{header|Oz}}==