Hi Dieter,
i have a query like as follows
SELECT c.unit_num
,c.trans_end_dt
,c.Coupon_cd AS Coupon_cd
,COUNT(DISTINCT Loyalty_Member_Id ) AS "Customer count"
,SUM(Net_Sales_Amt) AS Sales
,COUNT(Wgt_Item_Cnt) AS Units
,COUNT (DISTINCT c.rtl_trans_id) AS Transactions
,SUM(Discount_Amt) Disc_Amt
,SUM(coupon_qty) AS "Coupon quantity"
FROM
(SELECT
a.rtl_trans_id AS rtl_trans_id
,a.Trans_End_Dt AS Trans_End_Dt
,a. Mfr_Cpn_Scan_Cd AS Coupon_cd
,b.unit_num
,SUM(a.Mfr_Cpn_Amt ) AS Discount_Amt
,COUNT(DISTINCT rtl_trans_id) AS coupon_qty
FROM Merch_AV.RtlSaleMfrCpn a
JOIN merch_av.FlatOrgHierarchyAsIs b
ON a.org_id =b.store_id
AND Mfr_Cpn_Scan_Cd = 110100360000
AND trans_end_dt BETWEEN 1120717 AND 1120811
AND trans_type_cd = 0
WHERE org_level_03_num=84 AND org_hierarchy_id=203 /* farm fresh */
GROUP BY 1,2,3,4)c
INNER JOIN merch_av.Rtlsale d
ON c.Rtl_Trans_Id = d.Rtl_Trans_Id
AND c.Trans_End_Dt = d.Trans_End_Dt
AND trans_type_cd=0
GROUP BY 1,2,3
ORDER BY 1;
and explain plan as follows for this is as follows
/---------------------------
Explain SELECT c.unit_num
,c.trans_end_dt
,c.Coupon_cd AS Coupon_cd
,COUNT(DISTINCT Loyalty_Member_Id ) AS "Customer count"
,SUM(Net_Sales_Amt) AS Sales
,COUNT(Wgt_Item_Cnt) AS Units
,COUNT (DISTINCT c.rtl_trans_id) AS Transactions
,SUM(Discount_Amt) Disc_Amt
,SUM(coupon_qty) AS "Coupon quantity"
FROM
(SELECT
a.rtl_trans_id AS rtl_trans_id
,a.Trans_End_Dt AS Trans_End_Dt
,a. Mfr_Cpn_Scan_Cd AS Coupon_cd
,b.unit_num
,SUM(a.Mfr_Cpn_Amt ) AS Discount_Amt
,COUNT(DISTINCT rtl_trans_id) AS coupon_qty
FROM Merch_AV.RtlSaleMfrCpn a
JOIN merch_av.FlatOrgHierarchyAsIs b
ON a.org_id =b.store_id
AND Mfr_Cpn_Scan_Cd = 110100360000
AND trans_end_dt BETWEEN 1120717 AND 1120811
AND trans_type_cd = 0
WHERE org_level_03_num=84 AND org_hierarchy_id=203 /* farm fresh */
GROUP BY 1,2,3,4)c
INNER JOIN merch_av.Rtlsale d
ON c.Rtl_Trans_Id = d.Rtl_Trans_Id
AND c.Trans_End_Dt = d.Trans_End_Dt
AND trans_type_cd=0
GROUP BY 1,2,3
ORDER BY 1;
1) First, we lock SVUEDW_T.RtlSaleMfrCpn for access, we lock
SVUEDW_T.RtlSale in view merch_av.Rtlsale for access, and we lock
SVUEDW_A.FlatOrgHierarchyAsIs for access.
2) Next, we do an all-AMPs JOIN step from
SVUEDW_A.FlatOrgHierarchyAsIs by way of a RowHash match scan with
a condition of ("(SVUEDW_A.FlatOrgHierarchyAsIs.Org_Level_03_Num =
84) AND ((SVUEDW_A.FlatOrgHierarchyAsIs.Org_Hierarchy_Id = 203)
AND ((NOT (SVUEDW_A.FlatOrgHierarchyAsIs.Org_Level_03_Desc LIKE
'%SAVE-A-LOT%')) AND (NOT
(SVUEDW_A.FlatOrgHierarchyAsIs.Org_Level_03_Desc LIKE '%SAVE A
LOT%'))))"), which is joined to SVUEDW_A.FlatOrgHierarchyAsIs by
way of a RowHash match scan with a condition of (
"(SVUEDW_A.FlatOrgHierarchyAsIs.Org_Hierarchy_Id = 203) AND ((NOT
(SVUEDW_A.FlatOrgHierarchyAsIs.Org_Level_03_Desc LIKE
'%SAVE-A-LOT%')) AND (NOT
(SVUEDW_A.FlatOrgHierarchyAsIs.Org_Level_03_Desc LIKE '%SAVE A
LOT%')))") locking SVUEDW_A.FlatOrgHierarchyAsIs for access.
SVUEDW_A.FlatOrgHierarchyAsIs and SVUEDW_A.FlatOrgHierarchyAsIs
are joined using a merge join, with a join condition of (
"(SVUEDW_A.FlatOrgHierarchyAsIs.Org_Hierarchy_Id =
SVUEDW_A.FlatOrgHierarchyAsIs.Org_Hierarchy_Id) AND
(SVUEDW_A.FlatOrgHierarchyAsIs.Store_Id =
SVUEDW_A.FlatOrgHierarchyAsIs.Store_Id)"). The result goes into
Spool 4 (all_amps) (compressed columns allowed), which is
duplicated on all AMPs. The size of Spool 4 is estimated with low
confidence to be 34,125 rows (989,625 bytes). The estimated time
for this step is 0.02 seconds.
3) We do an all-AMPs JOIN step from Spool 4 (Last Use) by way of an
all-rows scan, which is joined to 26 partitions of
SVUEDW_T.RtlSaleMfrCpn with a condition of (
"(SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt >= DATE '2012-07-17') AND
((SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt <= DATE '2012-08-11') AND
((SVUEDW_T.RtlSaleMfrCpn.Mfr_Cpn_Scan_Cd = 110100360000.
) AND (SVUEDW_T.RtlSaleMfrCpn.Trans_Type_Cd = 0 )))"). Spool 4 and
SVUEDW_T.RtlSaleMfrCpn are joined using a dynamic hash join, with
a join condition of ("(SVUEDW_T.RtlSaleMfrCpn.Org_Id = Store_Id)
AND (SVUEDW_T.RtlSaleMfrCpn.Org_Id = Store_Id)"). The input table
SVUEDW_T.RtlSaleMfrCpn will not be cached in memory. The result
goes into Spool 3 (all_amps) (compressed columns allowed), which
is built locally on the AMPs. The size of Spool 3 is estimated
with low confidence to be 16,240 rows (893,200 bytes). The
estimated time for this step is 0.09 seconds.
4) We do an all-AMPs SUM step to aggregate from Spool 3 (Last Use) by
way of an all-rows scan , grouping by field1 (
SVUEDW_T.RtlSaleMfrCpn.Rtl_Trans_Id
,SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt
,SVUEDW_T.RtlSaleMfrCpn.Mfr_Cpn_Scan_Cd
,SVUEDW_A.FlatOrgHierarchyAsIs.Unit_Num
,SVUEDW_T.RtlSaleMfrCpn.Rtl_Trans_Id). Aggregate Intermediate
Results are computed locally, then placed in Spool 6. The size of
Spool 6 is estimated with low confidence to be 16,240 rows (
1,770,160 bytes). The estimated time for this step is 0.01
seconds.
5) We do an all-AMPs SUM step to aggregate from Spool 6 (Last Use) by
way of an all-rows scan , grouping by field1 (
SVUEDW_T.RtlSaleMfrCpn.Rtl_Trans_Id
,SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt
,SVUEDW_T.RtlSaleMfrCpn.Mfr_Cpn_Scan_Cd
,SVUEDW_A.FlatOrgHierarchyAsIs.Unit_Num). Aggregate Intermediate
Results are computed globally, then placed in Spool 8. The size
of Spool 8 is estimated with low confidence to be 16,240 rows (
1,705,200 bytes). The estimated time for this step is 0.02
seconds.
6) We do an all-AMPs RETRIEVE step from Spool 8 (Last Use) by way of
an all-rows scan into Spool 1 (used to materialize view, derived
table or table function c) (all_amps) (compressed columns allowed),
which is built locally on the AMPs. The size of Spool 1 is
estimated with low confidence to be 16,240 rows (1,250,480 bytes).
The estimated time for this step is 0.01 seconds.
7) We do an all-AMPs RETRIEVE step from Spool 1 (Last Use) by way of
an all-rows scan with a condition of ("NOT (c.RTL_TRANS_ID IS NULL)")
into Spool 13 (all_amps) (compressed columns allowed), which is
redistributed by the rowkey of (
SVUEDW_T.RtlSaleMfrCpn.Rtl_Trans_Id,
SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt) to all AMPs. Then we do a
SORT to partition Spool 13 by rowkey. The size of Spool 13 is
estimated with low confidence to be 16,240 rows (1,120,560 bytes).
The estimated time for this step is 0.01 seconds.
8) We do an all-AMPs JOIN step from SVUEDW_T.RtlSale in view
merch_av.Rtlsale by way of a RowHash match scan with a condition
of ("SVUEDW_T.RtlSale in view merch_av.Rtlsale.Trans_Type_Cd = 0"),
which is joined to Spool 13 (Last Use) by way of a RowHash match
scan. SVUEDW_T.RtlSale and Spool 13 are joined using a
rowkey-based merge join, with a join condition of ("(TRANS_END_DT
= SVUEDW_T.RtlSale.Trans_End_Dt) AND (RTL_TRANS_ID =
SVUEDW_T.RtlSale.Rtl_Trans_Id)"). The input table
SVUEDW_T.RtlSale will not be cached in memory, but it is eligible
for synchronized scanning. The result goes into Spool 14
(all_amps) (compressed columns allowed), which is redistributed by
the hash code of (SVUEDW_T.RtlSale.Org_Id, 203) to all AMPs. Then
we do a SORT to order Spool 14 by row hash. The size of Spool 14
is estimated with low confidence to be 16,081 rows (1,350,804
bytes). The estimated time for this step is 0.20 seconds.
9) We do an all-AMPs JOIN step from Spool 14 (Last Use) by way of a
RowHash match scan, which is joined to
SVUEDW_A.FlatOrgHierarchyAsIs in view merch_av.Rtlsale by way of a
RowHash match scan with a condition of (
"(SVUEDW_A.FlatOrgHierarchyAsIs in view
merch_av.Rtlsale.Org_Hierarchy_Id = 203) AND ((NOT
(SVUEDW_A.FlatOrgHierarchyAsIs in view
merch_av.Rtlsale.Org_Level_03_Desc LIKE '%SAVE-A-LOT%')) AND (NOT
(SVUEDW_A.FlatOrgHierarchyAsIs in view
merch_av.Rtlsale.Org_Level_03_Desc LIKE '%SAVE A LOT%')))")
locking SVUEDW_A.FlatOrgHierarchyAsIs for access. Spool 14 and
SVUEDW_A.FlatOrgHierarchyAsIs are joined using a merge join, with
a join condition of ("Org_Id =
SVUEDW_A.FlatOrgHierarchyAsIs.Store_Id"). The result goes into
Spool 12 (all_amps) (compressed columns allowed), which is built
locally on the AMPs. The size of Spool 12 is estimated with low
confidence to be 15,370 rows (1,244,970 bytes). The estimated
time for this step is 0.01 seconds.
10) We do an all-AMPs SUM step to aggregate from Spool 12 by way of an
all-rows scan , grouping by field1 (
SVUEDW_A.FlatOrgHierarchyAsIs.Unit_Num
,SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt
,SVUEDW_T.RtlSaleMfrCpn.Mfr_Cpn_Scan_Cd
,SVUEDW_T.RtlSaleMfrCpn.Rtl_Trans_Id). Aggregate Intermediate
Results are computed globally, then placed in Spool 19. The size
of Spool 19 is estimated with low confidence to be 15,370 rows (
1,767,550 bytes). The estimated time for this step is 0.02
seconds.
11) We do an all-AMPs SUM step to aggregate from Spool 19 (Last Use)
by way of an all-rows scan , grouping by field1 (
SVUEDW_A.FlatOrgHierarchyAsIs.Unit_Num
,SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt
,SVUEDW_T.RtlSaleMfrCpn.Mfr_Cpn_Scan_Cd). Aggregate Intermediate
Results are computed globally, then placed in Spool 21. The size
of Spool 21 is estimated with low confidence to be 2,157 rows (
243,741 bytes). The estimated time for this step is 0.02 seconds.
12) We execute the following steps in parallel.
1) We do an all-AMPs RETRIEVE step from Spool 21 (Last Use) by
way of an all-rows scan into Spool 16 (all_amps) (compressed
columns allowed), which is built locally on the AMPs. The
size of Spool 16 is estimated with low confidence to be 2,157
rows (183,345 bytes). The estimated time for this step is
0.01 seconds.
2) We do an all-AMPs SUM step to aggregate from Spool 12 (Last
Use) by way of an all-rows scan , grouping by field1 (
SVUEDW_A.FlatOrgHierarchyAsIs.Unit_Num
,SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt
,SVUEDW_T.RtlSaleMfrCpn.Mfr_Cpn_Scan_Cd
,SVUEDW_T.RtlSale.Loyalty_Member_Id). Aggregate Intermediate
Results are computed globally, then placed in Spool 25. The
size of Spool 25 is estimated with low confidence to be 15,370
rows (1,060,530 bytes). The estimated time for this step is
0.02 seconds.
13) We do an all-AMPs SUM step to aggregate from Spool 25 (Last Use)
by way of an all-rows scan , grouping by field1 (
SVUEDW_A.FlatOrgHierarchyAsIs.Unit_Num
,SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt
,SVUEDW_T.RtlSaleMfrCpn.Mfr_Cpn_Scan_Cd). Aggregate Intermediate
Results are computed globally, then placed in Spool 27. The size
of Spool 27 is estimated with low confidence to be 2,157 rows (
131,577 bytes). The estimated time for this step is 0.02 seconds.
14) We execute the following steps in parallel.
1) We do an all-AMPs RETRIEVE step from Spool 27 (Last Use) by
way of an all-rows scan into Spool 15 (all_amps) (compressed
columns allowed), which is built locally on the AMPs. The
size of Spool 15 is estimated with low confidence to be 2,157
rows (97,065 bytes). The estimated time for this step is 0.01
seconds.
2) We do an all-AMPs RETRIEVE step from Spool 16 (Last Use) by
way of an all-rows scan into Spool 29 (all_amps) (compressed
columns allowed), which is redistributed by the hash code of (
SVUEDW_A.FlatOrgHierarchyAsIs.Unit_Num,
SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt,
SVUEDW_T.RtlSaleMfrCpn.Mfr_Cpn_Scan_Cd) to all AMPs. Then we
do a SORT to order Spool 29 by row hash. The size of Spool 29
is estimated with low confidence to be 2,157 rows (166,089
bytes). The estimated time for this step is 0.01 seconds.
15) We do an all-AMPs RETRIEVE step from Spool 15 (Last Use) by way of
an all-rows scan into Spool 30 (all_amps) (compressed columns
allowed), which is redistributed by the hash code of (
SVUEDW_A.FlatOrgHierarchyAsIs.Unit_Num,
SVUEDW_T.RtlSaleMfrCpn.Trans_End_Dt,
SVUEDW_T.RtlSaleMfrCpn.Mfr_Cpn_Scan_Cd) to all AMPs. Then we do a
SORT to order Spool 30 by row hash. The size of Spool 30 is
estimated with low confidence to be 2,157 rows (79,809 bytes).
The estimated time for this step is 0.01 seconds.
16) We do an all-AMPs JOIN step from Spool 29 (Last Use) by way of a
RowHash match scan, which is joined to Spool 30 (Last Use) by way
of a RowHash match scan. Spool 29 and Spool 30 are joined using a
merge join, with a join condition of ("(COUPON_CD = COUPON_CD) AND
((TRANS_END_DT = TRANS_END_DT) AND (UNIT_NUM = UNIT_NUM ))"). The
result goes into Spool 10 (group_amps), which is built locally on
the AMPs. Then we do a SORT to order Spool 10 by the sort key in
spool field1 (SVUEDW_A.FlatOrgHierarchyAsIs.Unit_Num). The size
of Spool 10 is estimated with low confidence to be 1,967 rows (
175,063 bytes). The estimated time for this step is 0.01 seconds.
17) Finally, we send out an END TRANSACTION step to all AMPs involved
in processing the request.
-> The contents of Spool 10 are sent back to the user as the result
of statement 1. The total estimated time is 0.47 seconds.
-----------/
in this plan in step2 it is get duplicated in all amps i want to know why it is happening like this and how to convert this from low confidence to high confidence?
Thanks in advance
↧