[ 
https://issues.apache.org/jira/browse/IGNITE-7908?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Ilya Kasnacheev updated IGNITE-7908:
------------------------------------
    Priority: Major  (was: Critical)

> NULLS LAST works incorrectly for PARTITIONED caches
> ---------------------------------------------------
>
>                 Key: IGNITE-7908
>                 URL: https://issues.apache.org/jira/browse/IGNITE-7908
>             Project: Ignite
>          Issue Type: Bug
>          Components: sql
>            Reporter: Stanislav Lukyanov
>            Priority: Major
>
> When a `SELECT .... ORDER BY ... NULLS LAST` query is executed on a 
> partitioned cache, the null values at the end of the result are interleaved 
> with non-null values. 
> It seems that for each node participating in the query all null values that 
> are stored on that node are returned immediately after the last non-null 
> value. As a result, non-null values are correctly ordered and null values 
> appear in a few "portions" (the number of "portions" is equal to the number 
> of nodes) among the last values.
> Example:
>  ====================
> {code:java}
> public class NullsLastBug {
>     public static void main(String[] args) throws Exception {
>         try (
>             Ignite srv1 = 
> IgnitionEx.start("examples/config/example-ignite.xml", "server-1");
>             Ignite srv2 = 
> IgnitionEx.start("examples/config/example-ignite.xml", "server-2");
>             Ignite srv3 = 
> IgnitionEx.start("examples/config/example-ignite.xml", "server-3")
>         ) {
>             Ignition.setClientMode(true);
>             try (Ignite client = 
> IgnitionEx.start("examples/config/example-ignite.xml", "client")) {
>                 IgniteCache<Long, Box> cache = client.getOrCreateCache(
>                     new CacheConfiguration<Long, Box>("cache")
>                         .setCacheMode(CacheMode.PARTITIONED)
>                         .setIndexedTypes(Long.class, Box.class)
>                 );
>                 for (long i = 0; i < 30; i++) {
>                     Long num = (i % 2 != 0) ? i : null;
>                     cache.put(i, new Box(num));
>                 }
>                 SqlFieldsQuery selectAll = new SqlFieldsQuery("SELECT num 
> FROM Box ORDER BY num NULLS LAST");
>                 for (List<?> list : cache.query(selectAll))
>                     System.out.println(list);
>             }
>         }
>     }
> }
> class Box implements Serializable {
>     @QuerySqlField(index = true) private Long num;
>     Box(Long num) {
>         this.num = num;
>     }
> }
> {code}
>  ====================
> Output:
>  ====================
> {code}
>  [1]
>  [3]
>  [5]
>  [7]
>  [9]
>  [11]
>  [13]
>  [15]
>  [17]
>  [19]
>  [21]
>  [23]
>  [null]
>  [null]
>  [25]
>  [27]
>  [null]
>  [null]
>  [null]
>  [null]
>  [null]
>  [null]
>  [null]
>  [null]
>  [29]
>  [null]
>  [null]
>  [null]
>  [null]
>  [null]
> {code}
>  ====================



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