-- -- WORKER_HASH_PARTITION -- ALTER SEQUENCE pg_catalog.pg_dist_shardid_seq RESTART 1130000; ALTER SEQUENCE pg_catalog.pg_dist_jobid_seq RESTART 1130000; \set JobId 201010 \set TaskId 101103 \set Partition_Column l_orderkey \set Partition_Column_Text '\'l_orderkey\'' \set Partition_Column_Type '\'int8\'' \set Partition_Count 4 \set Select_Query_Text '\'SELECT * FROM lineitem\'' \set Select_All 'SELECT *' -- Hash functions internally return unsigned 32-bit integers. However, when -- called externally, the return value becomes a signed 32-bit integer. We hack -- around this conversion issue by bitwise-anding the hash results. Note that -- this only works because we are modding with 4. The proper Hash_Mod_Function -- would be (case when hashint8(l_orderkey) >= 0 then (hashint8(l_orderkey) % 4) -- else ((hashint8(l_orderkey) + 4294967296) % 4) end). \set Hash_Mod_Function '( (hashint8(l_orderkey) & 2147483647) % 4 )' \set Table_Part_00 lineitem_hash_part_00 \set Table_Part_01 lineitem_hash_part_01 \set Table_Part_02 lineitem_hash_part_02 \set Table_Part_03 lineitem_hash_part_03 -- Run select query, and apply hash partitioning on query results SELECT worker_hash_partition_table(:JobId, :TaskId, :Select_Query_Text, :Partition_Column_Text, :Partition_Column_Type::regtype, :Partition_Count); COPY :Table_Part_00 FROM 'base/pgsql_job_cache/job_201010/task_101103/p_00000'; COPY :Table_Part_01 FROM 'base/pgsql_job_cache/job_201010/task_101103/p_00001'; COPY :Table_Part_02 FROM 'base/pgsql_job_cache/job_201010/task_101103/p_00002'; COPY :Table_Part_03 FROM 'base/pgsql_job_cache/job_201010/task_101103/p_00003'; SELECT COUNT(*) FROM :Table_Part_00; SELECT COUNT(*) FROM :Table_Part_03; -- We first compute the difference of partition tables against the base table. -- Then, we compute the difference of the base table against partitioned tables. SELECT COUNT(*) AS diff_lhs_00 FROM ( :Select_All FROM :Table_Part_00 EXCEPT ALL :Select_All FROM lineitem WHERE (:Hash_Mod_Function = 0) ) diff; SELECT COUNT(*) AS diff_lhs_01 FROM ( :Select_All FROM :Table_Part_01 EXCEPT ALL :Select_All FROM lineitem WHERE (:Hash_Mod_Function = 1) ) diff; SELECT COUNT(*) AS diff_lhs_02 FROM ( :Select_All FROM :Table_Part_02 EXCEPT ALL :Select_All FROM lineitem WHERE (:Hash_Mod_Function = 2) ) diff; SELECT COUNT(*) AS diff_lhs_03 FROM ( :Select_All FROM :Table_Part_03 EXCEPT ALL :Select_All FROM lineitem WHERE (:Hash_Mod_Function = 3) ) diff; SELECT COUNT(*) AS diff_rhs_00 FROM ( :Select_All FROM lineitem WHERE (:Hash_Mod_Function = 0) EXCEPT ALL :Select_All FROM :Table_Part_00 ) diff; SELECT COUNT(*) AS diff_rhs_01 FROM ( :Select_All FROM lineitem WHERE (:Hash_Mod_Function = 1) EXCEPT ALL :Select_All FROM :Table_Part_01 ) diff; SELECT COUNT(*) AS diff_rhs_02 FROM ( :Select_All FROM lineitem WHERE (:Hash_Mod_Function = 2) EXCEPT ALL :Select_All FROM :Table_Part_02 ) diff; SELECT COUNT(*) AS diff_rhs_03 FROM ( :Select_All FROM lineitem WHERE (:Hash_Mod_Function = 3) EXCEPT ALL :Select_All FROM :Table_Part_03 ) diff;