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1. Create the sample table. Use CREATE TABLE tab1_sample LIKE tab1 WITH PARTITIONS;
2. CQD HBASE_NUM_CACHE_ROWS_MAX '1' ; – or some other low number like 10 may work too.
3. CQD PARALLEL_NUM_ESPS <num_of_partitions> – this is the number of salt values for salted tables
4. UPSERT USING LOAD INTO tab1_sample SELECT * FROM tab1 SAMPLE RANDOM <x> PERCENT ROWS ; – <x> is computed to result in 1 million rows. We have to know approximate cardinality of tab1. This can be obtained by running an explain query like "EXPLAIN OPTION 'f' SELECT * FROM tab1"
5. cqd USTAT_SAMPLE_TABLE_NAME 'trafodion.<sch-name>.tab1_sample' ;
6. UPDATE STATISTICS FOR TABLE tab1 ON EVERY COLUMN SAMPLE <y> ROWS ; — <y> is the number of rows inserted in step 4.; 

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