Кто-нибудь может мне помочь настроить View на основе плана объяснения?
Выбор причины просмотра TDWM Ошибка. Это использует больше чем> 100 КБ процессора. Мне трудно читать объяснительный план в Teradata, так что вы, ребята, можете помочь мне решить проблему?
У меня есть первичный индекс IDN, а также вторичный индекс PARENT_ID.
This query is optimized using type 2 profile nonested_cost, profileid
10003.
1) First, we lock 'table_name' in view 'view_name' in TD_MAP1 for read
on a reserved RowHash to prevent global deadlock.
2) Next, we lock 'table_name' in view 'view_name' in TD_MAP1 for read.
3) We do an all-AMPs RETRIEVE step in TD_MAP1 from 'table_name' in view
'view_name' by way of an all-rows scan with a condition of (
"'table_name' in view 'view_name'.A = 'X'") into Spool 7 (all_amps),
which is redistributed by the hash code of ('table_name'.IDN) to all
AMPs in TD_Map1. Then we do a SORT to order Spool 7 by row hash.
The size of Spool 7 is estimated with high confidence to be 562,323
rows (16,307,367 bytes). The estimated time for this step is 0.07
seconds.
4) We do an all-AMPs JOIN step in TD_MAP1 from 'table_name' in view
'view_name' by way of a RowHash match scan with a condition of (
"((CAST(('table_name' in view 'view_name'.DATE) AS DATE))>=DATE
'2018-01-01') AND (('table_name' in view 'view_name'.A IN ('X','Y',
'Z')) AND ('table_name' in view 'view_name'.C <> 'XXX'))"), which
is joined to Spool 7 (Last Use) by way of a RowHash match scan.
'table_name' and Spool 7 are joined using a merge join, with a join
condition of ("'table_name'.PARENT_ID = IDN"). The result goes into
Spool 6 (all_amps), which is built locally on the AMPs. The size of
Spool 6 is estimated with low confidence to be 562,323 rows
(308,715,327 bytes). The estimated time for this step is 0.03
seconds.
5) We do an all-AMPs RETRIEVE step in TD_Map1 from Spool 6 by way of
an all-rows scan with a condition of ("(NOT (R.K0 IS NULL )) AND
((NOT (R.K2 IS NULL )) AND (R.K0D <= R.K2D ))") into Spool 2
(all_amps), which is built locally on the AMPs. The size of Spool
2 is estimated with no confidence to be 562,323 rows (308,715,327
bytes). The estimated time for this step is 0.04 seconds.
6) We do an all-AMPs RETRIEVE step in TD_Map1 from Spool 6 (Last Use)
by way of an all-rows scan with a condition of (
"TD_RECURSIVE_REF.DEPTH <= 264") into Spool 8 (all_amps), which is
redistributed by the hash code of (
'table_name'.IDN)
to all AMPs in TD_Map1. The size of Spool 8 is estimated with no
confidence to be 562,323 rows (297,468,867 bytes). The estimated
time for this step is 0.14 seconds.
7) We do an all-AMPs JOIN step in TD_MAP1 from 'table_name' in view
'view_name' by way of an all-rows scan with a condition of (
"'table_name' in view 'view_name'.PLANT IN ('X','Y,'Z')"), which
is joined to Spool 8 (Last Use) by way of an all-rows scan.
'table_name' and Spool 8 are joined using a single partition hash
join, with a join condition of ("K1 ='table_name'.ID"). The result
goes into Spool 9 (all_amps), which is built locally on the AMPs.
The size of Spool 9 is estimated with no confidence to be 562,323
rows (308,715,327 bytes). The estimated time for this step is 0.06
seconds.
8) We do an all-AMPs RETRIEVE step in TD_Map1 from Spool 9 (Last Use)
by way of an all-rows scan into Spool 6 (all_amps), which is built
locally on the AMPs. The size of Spool 6 is estimated with no
confidence to be 28,678,473 rows (15,744,481,677 bytes). The
estimated time for this step is 0.04 seconds. If one or more rows
are inserted into spool 6, then go to step 5.
9) We do an all-AMPs RETRIEVE step in TD_Map1 from Spool 2 (Last Use)
by way of an all-rows scan with a condition of ("(NOT (R.K0 IS
NULL )) AND ((NOT (R.K2 IS NULL )) AND (R.K0D <= R.K2D ))") into
Spool 5 (all_amps), which is built locally on the AMPs. The size
of Spool 5 is estimated with no confidence to be 28,678,473 rows (
14,253,201,081 bytes). The estimated time for this step is 1.56
seconds.
10) We do an all-AMPs STAT FUNCTION step in TD_Map1 from Spool 5 (Last
Use) by way of an all-rows scan into Spool 12 (Last Use), which is
assumed to be redistributed by value to all AMPs in TD_Map1. The
result rows are put into Spool 10 (all_amps), which is built
locally on the AMPs. The size is estimated with no confidence to
be 28,678,473 rows (14,482,628,865 bytes).
11) We do an all-AMPs RETRIEVE step in TD_Map1 from Spool 10 (Last
Use) by way of an all-rows scan into Spool 3 (used to materialize
view, derived table, table function or table operator X)
(all_amps), which is redistributed by the hash code of (Field_35
(INTEGER), Field_34, K2D, K2Q, K2DI, K2MU, K2MT, K2MN, K2M, K2BD,
K2PSN, K2PUN, K2MCN, K2MC, K2BN, K2PN, K2PC, K0D, K0Q, K0DI, K0MU,
K0MT, K0MN, K0M, K0BD, K0PSN, K0PUN, K0MCN, K0MC, K0BN, K0PN, K0PC,
K2, K0) to all AMPs in TD_Map1. Then we do a SORT to order Spool
3 by the sort key in spool field1 eliminating duplicate rows. The
size of Spool 3 is estimated with no confidence to be 21,508,855
rows (35,554,137,315 bytes). The estimated time for this step is
7.09 seconds.
12) We do an all-AMPs SUM step in TD_Map1 to aggregate from Spool 3
(Last Use) by way of an all-rows scan with a condition of (
"X.END_LAST_MOVE = 1"), and the grouping identifier in field
1. Aggregate Intermediate Results are computed globally, then
placed in Spool 4 in TD_Map1. The size of Spool 4 is estimated
with no confidence to be 16,131,642 rows (25,504,126,002 bytes).
The estimated time for this step is 38.74 seconds.
13) Finally, we send out an END TRANSACTION step to all AMPs involved
in processing the request.
-> The contents of Spool 4 are sent back to the user as the result of
statement 1.