ERROR 2013 (HY000): Lost connection to MySQL server during query

[Helen Yelluas]

Hello everyone,

I have a problem running a simple query from merge table
The table has 22 columns , 15 keys, 3 members with exact set of indecies
Merge table has the same set.

select from each member work fine,

select count(1) from ProfilerEventMin_1441909 where DestReportObjectID=5 and SrcUserGroupID=2 and DestPort=80;
0

select count(1) from ProfilerEvent where DestReportObjectID=5 and SrcUserGroupID=2 and DestPort=80;
ERROR 2013 (HY000): Lost connection to MySQL server during query

select count(1) from ProfilerEvent where DestReportObjectID=5 and SrcUserGroupID=2 and DestPort=8;
+----------+
| count(1) |
+----------+
| 0 |
+----------+

any idea why merge table crashes on the indecies?
any setting should I check?

thank you
helen