Re: Scan.addFamiliy reduces results

[Peter Wolf]

Thanks Doug,

I had read that, and I just read it again.  But I am missing something...
Why does adding a family reduce the number of results?  Is there an 
implied filter of some form?  Does addFamily add some constraint on 
which rows are returned?

Note that all my rows *ought* to have values in all the families.

Thanks
Peter

On 3/15/12 12:39 PM, Doug Meil wrote:
re:  "However, I am getting different number of results, depending on
which families are added"

Yes.

I'd suggest you read this in the RefGuide.

http://hbase.apache.org/book.html#datamodel





On 3/15/12 12:08 PM, "Peter Wolf"<opus...@gmail.com>  wrote:

Hi all,

I am doing a scan on a table with multiple families.  My code looks like
this...

         Scan scan = new Scan(calculateStartRowKey(a),
calculateEndRowKey(b));

         scan.setCaching(10000);
         Filter filter = new SingleColumnValueFilter(xFamily, xColumn,
CompareFilter.CompareOp.EQUAL, Bytes.toBytes(x));
         scan.setFilter(filter);
         scan
                 .addFamily(xFamily)
                 .addFamily(yFamily)
                 .addFamily(zFamily);

         ResultScanner scanner = hTable.getScanner(scan);

         Iterator<Result>  it = scanner.iterator();
         int resultCount = 0;
         while (it.hasNext()) {
               Result result = it.next();

               resultCount++;
         }

However, I am getting different number of results, depending on which
families are added.  For example these give different result counts

         scan
                 //.addFamily(xFamily)
                 .addFamily(yFamily)
                 .addFamily(zFamily);
and
         scan
                 .addFamily(xFamily)
                 .addFamily(yFamily)
                 .addFamily(zFamily);


There is no error message, and I don't see anything in the Scan
documentation.  Does anyone know what is going on?

Thanks
Peter