我正面临着临时空间和温度之间的权衡问题。查询性能。
我的场景是这样的：我有一个庞大的事务表（25个分区中有200亿条记录）和一个包含7条记录的小型度量查找表。我需要处理每个指标记录的每个交易记录。基本上输出将是7 * 200亿条记录。此输出必须基于5-6列进行汇总。
我考虑过两个选择：
交叉连接这两个表并使用“case when”指定处理逻辑wrt metric并执行“group by”操作。
对每个指标ID有七个不同的查询，对结果有“UNION ALL”。
＃1消耗大约250 GB的巨大临时空间，＃2运行大约230分钟。
有没有办法，我可以优化其中一个选项？我需要在60分钟内完成此查询。
添加查询
@david查询粘贴在
下面WITH IDQ_LKP AS
(SELECT '703' AS METRIC_ID,'desc1' AS EN_METRIC_1_NM
FROM DUAL
UNION ALL
SELECT '702' AS METRIC_ID,'desc1' AS EN_METRIC_1_NM
FROM DUAL
UNION ALL
SELECT '704' AS METRIC_ID,'% desc1' AS EN_METRIC_1_NM
FROM DUAL
UNION ALL
SELECT '705' AS METRIC_ID,'desc2' AS EN_METRIC_1_NM
FROM DUAL
UNION ALL
SELECT '706' AS METRIC_ID,'desc3' AS EN_METRIC_1_NM
FROM DUAL
UNION ALL
SELECT '707' AS METRIC_ID,'desc5' AS EN_METRIC_1_NM
FROM DUAL
UNION ALL
SELECT '701' AS METRIC_ID,'desc4' AS EN_METRIC_1_NM
FROM DUAL)
SELECT /*+ parallel(16) USE_HASH_AGGREGATION */ col1 ,
col2 ,
'Monthly Snapshots' AS Time_Rollup , col3 , date_pk , colr , col5 , colr_DESC , col5_DESC , metric_id , EN_METRIC_1_NM , sum (
CASE
WHEN (metric_id='704'
AND record_identifier=17 )
OR (metric_id='705'
AND record_identifier=123)
OR (metric_id='706'
AND record_identifier=43)
OR (metric_id='707'
AND record_identifier=34) THEN
nvl ( record_count,0 )
WHEN metric_id NOT IN ('704','705','706','707') THEN
NULL
ELSE 0
END ) AS METRIC_1_CY , NULL AS METRIC_1_LY , sum (
CASE
WHEN (metric_id='703'
AND record_identifier=17)
OR (metric_id='705'
AND record_identifier=777 )
OR (metric_id='702'
AND record_identifier=123 )
OR (metric_id='704'
AND record_identifier=17 )
OR (metric_id='706'
AND record_identifier=99999997 )
OR (metric_id='707'
AND record_identifier=99999996) THEN
nvl ( record_count,0 )
WHEN metric_id NOT IN ('702','703','704','705','706','707') THEN
NULL
ELSE 0
END ) AS METRIC_2_CY , NULL AS METRIC_2_LY , NULL AS METRIC_3_CY , NULL AS METRIC_3_LY
FROM TXN,LKP
WHERE col1=2
GROUP BY col1 , col2 , col3 , date_pk , colr , col5 , colr_DESC , col5_DESC, metric_id , EN_METRIC_1_NM
嗨，
我仍然在解释计划中看到252 GB需要临时空间......
-------------------------------------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes |TempSpc| Cost | Pstart| Pstop | TQ |IN-OUT| PQ Distrib |
-------------------------------------------------------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | | 17M| | | | | |
| 1 | PX COORDINATOR | | | | | | | | | | |
| 2 | PX SEND QC (RANDOM) | :TQ10003 | 1894M| 217G| | 17M| | | Q1,03 | P->S | QC (RAND) |
| 3 | HASH GROUP BY | | 1894M| 217G| 262G| 17M| | | Q1,03 | PCWP | |
| 4 | PX RECEIVE | | 1894M| 217G| | 17M| | | Q1,03 | PCWP | |
| 5 | PX SEND HASH | :TQ10002 | 1894M| 217G| | 17M| | | Q1,02 | P->P | HASH |
| 6 | HASH GROUP BY | | 1894M| 217G| 262G| 17M| | | Q1,02 | PCWP | |
| 7 | MERGE JOIN CARTESIAN | | 1894M| 217G| | 149K| | | Q1,02 | PCWP | |
| 8 | BUFFER SORT | | | | | | | | Q1,02 | PCWC | |
| 9 | PX RECEIVE | | 7 | 154 | | 14 | | | Q1,02 | PCWP | |
| 10 | PX SEND BROADCAST | :TQ10000 | 7 | 154 | | 14 | | | | S->P | BROADCAST |
| 11 | VIEW | | 7 | 154 | | 14 | | | | | |
| 12 | UNION-ALL | | | | | | | | | | |
| 13 | FAST DUAL | | 1 | | | 2 | | | | | |
| 14 | FAST DUAL | | 1 | | | 2 | | | | | |
| 15 | FAST DUAL | | 1 | | | 2 | | | | | |
| 16 | FAST DUAL | | 1 | | | 2 | | | | | |
| 17 | FAST DUAL | | 1 | | | 2 | | | | | |
| 18 | FAST DUAL | | 1 | | | 2 | | | | | |
| 19 | FAST DUAL | | 1 | | | 2 | | | | | |
| 20 | BUFFER SORT | | 270M| 25G| | 17M| | | Q1,02 | PCWP | |
| 21 | VIEW | | 270M| 25G| | | | | Q1,02 | PCWP | |
| 22 | HASH GROUP BY | | 270M| 22G| 29G| 115K| | | Q1,02 | PCWP | |
| 23 | PX RECEIVE | | 270M| 22G| | 843 | | | Q1,02 | PCWP | |
| 24 | PX SEND HASH | :TQ10001 | 270M| 22G| | 843 | | | Q1,01 | P->P | HASH |
| 25 | PX BLOCK ITERATOR | | 270M| 22G| | 843 | 28 | 55 | Q1,01 | PCWC | |
|* 26 | TABLE ACCESS FULL| TXN | 270M| 22G| | 843 | 28 | 55 | Q1,01 | PCWP | |
---------------------------------------------------------------------------------------------------------
它现在正在运行......我怀疑它可能会陷入同样的问题......
计划“UNION ALL”方法..
-------------------------------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes |TempSpc| Cost | Pstart| Pstop | TQ |IN-OUT| PQ Distrib |
-------------------------------------------------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | | 774K| | | | | |
| 1 | UNION-ALL | | | | | | | | | | |
| 2 | PX COORDINATOR | | | | | | | | | | |
| 3 | PX SEND QC (RANDOM) | :TQ10001 | 270M| 18G| | 100K| | | Q1,01 | P->S | QC (RAND) |
| 4 | HASH GROUP BY | | 270M| 18G| 24G| 100K| | | Q1,01 | PCWP | |
| 5 | PX RECEIVE | | 270M| 18G| | 843 | | | Q1,01 | PCWP | |
| 6 | PX SEND HASH | :TQ10000 | 270M| 18G| | 843 | | | Q1,00 | P->P | HASH |
| 7 | PX BLOCK ITERATOR | | 270M| 18G| | 843 | 28 | 55 | Q1,00 | PCWC | |
|* 8 | TABLE ACCESS FULL| TXN | 270M| 18G| | 843 | 28 | 55 | Q1,00 | PCWP | |
| 9 | PX COORDINATOR | | | | | | | | | | |
| 10 | PX SEND QC (RANDOM) | :TQ20001 | 270M| 21G| | 112K| | | Q2,01 | P->S | QC (RAND) |
| 11 | HASH GROUP BY | | 270M| 21G| 28G| 112K| | | Q2,01 | PCWP | |
| 12 | PX RECEIVE | | 270M| 21G| | 843 | | | Q2,01 | PCWP | |
| 13 | PX SEND HASH | :TQ20000 | 270M| 21G| | 843 | | | Q2,00 | P->P | HASH |
| 14 | PX BLOCK ITERATOR | | 270M| 21G| | 843 | 28 | 55 | Q2,00 | PCWC | |
|* 15 | TABLE ACCESS FULL| TXN | 270M| 21G| | 843 | 28 | 55 | Q2,00 | PCWP | |
| 16 | PX COORDINATOR | | | | | | | | | | |
| 17 | PX SEND QC (RANDOM) | :TQ30001 | 270M| 21G| | 112K| | | Q3,01 | P->S | QC (RAND) |
| 18 | HASH GROUP BY | | 270M| 21G| 28G| 112K| | | Q3,01 | PCWP | |
| 19 | PX RECEIVE | | 270M| 21G| | 843 | | | Q3,01 | PCWP | |
| 20 | PX SEND HASH | :TQ30000 | 270M| 21G| | 843 | | | Q3,00 | P->P | HASH |
| 21 | PX BLOCK ITERATOR | | 270M| 21G| | 843 | 28 | 55 | Q3,00 | PCWC | |
|* 22 | TABLE ACCESS FULL| TXN | 270M| 21G| | 843 | 28 | 55 | Q3,00 | PCWP | |
| 23 | PX COORDINATOR | | | | | | | | | | |
| 24 | PX SEND QC (RANDOM) | :TQ40001 | 270M| 21G| | 112K| | | Q4,01 | P->S | QC (RAND) |
| 25 | HASH GROUP BY | | 270M| 21G| 28G| 112K| | | Q4,01 | PCWP | |
| 26 | PX RECEIVE | | 270M| 21G| | 843 | | | Q4,01 | PCWP | |
| 27 | PX SEND HASH | :TQ40000 | 270M| 21G| | 843 | | | Q4,00 | P->P | HASH |
| 28 | PX BLOCK ITERATOR | | 270M| 21G| | 843 | 28 | 55 | Q4,00 | PCWC | |
|* 29 | TABLE ACCESS FULL| TXN | 270M| 21G| | 843 | 28 | 55 | Q4,00 | PCWP | |
| 30 | PX COORDINATOR | | | | | | | | | | |
| 31 | PX SEND QC (RANDOM) | :TQ50001 | 270M| 21G| | 112K| | | Q5,01 | P->S | QC (RAND) |
| 32 | HASH GROUP BY | | 270M| 21G| 28G| 112K| | | Q5,01 | PCWP | |
| 33 | PX RECEIVE | | 270M| 21G| | 843 | | | Q5,01 | PCWP | |
| 34 | PX SEND HASH | :TQ50000 | 270M| 21G| | 843 | | | Q5,00 | P->P | HASH |
| 35 | PX BLOCK ITERATOR | | 270M| 21G| | 843 | 28 | 55 | Q5,00 | PCWC | |
|* 36 | TABLE ACCESS FULL| TXN | 270M| 21G| | 843 | 28 | 55 | Q5,00 | PCWP | |
| 37 | PX COORDINATOR | | | | | | | | | | |
| 38 | PX SEND QC (RANDOM) | :TQ60001 | 270M| 21G| | 112K| | | Q6,01 | P->S | QC (RAND) |
| 39 | HASH GROUP BY | | 270M| 21G| 28G| 112K| | | Q6,01 | PCWP | |
| 40 | PX RECEIVE | | 270M| 21G| | 843 | | | Q6,01 | PCWP | |
| 41 | PX SEND HASH | :TQ60000 | 270M| 21G| | 843 | | | Q6,00 | P->P | HASH |
| 42 | PX BLOCK ITERATOR | | 270M| 21G| | 843 | 28 | 55 | Q6,00 | PCWC | |
|* 43 | TABLE ACCESS FULL| TXN | 270M| 21G| | 843 | 28 | 55 | Q6,00 | PCWP | |
| 44 | PX COORDINATOR | | | | | | | | | | |
| 45 | PX SEND QC (RANDOM) | :TQ70001 | 270M| 21G| | 112K| | | Q7,01 | P->S | QC (RAND) |
| 46 | SORT GROUP BY | | 270M| 21G| 28G| 112K| | | Q7,01 | PCWP | |
| 47 | PX RECEIVE | | 270M| 21G| | 843 | | | Q7,01 | PCWP | |
| 48 | PX SEND HASH | :TQ70000 | 270M| 21G| | 843 | | | Q7,00 | P->P | HASH |
| 49 | PX BLOCK ITERATOR | | 270M| 21G| | 843 | 28 | 55 | Q7,00 | PCWC | |
|* 50 | TABLE ACCESS FULL| TXN | 270M| 21G| | 843 | 28 | 55 | Q7,00 | PCWP | |
-------------------------------------------------------------------------------------------------------------------------------------------
答案 0 :(得分：1)
只是查看查询，我考虑尝试的一种方法是改变这种实现方法：
......对此...
这应该需要更小的临时数据集。
答案 1 :(得分：1)
我对您的请求的评论在某种程度上闻所未闻。所以再次：为了避免巨大的中间数据，请事先减少它。请尝试以下方法。首先，大表预先聚合，然后交叉连接，然后再次聚合。这减少了笛卡尔积中的中间数据。这可以解决您的问题。
select
col1, col2, 'Monthly Snapshots' AS Time_Rollup, col3, date_pk, colr, col5, colr_DESC, col5_DESC, metric_id, en_metric_1_nm
, sum
(
case
when (metric_id='704' and record_identifier=17 )
or (metric_id='705' and record_identifier=123)
or (metric_id='706' and record_identifier=43)
or (metric_id='707' and record_identifier=34) then
sum_record_count
when metric_id not in ('704','705','706','707') then
null
else
0
end
) as metric_1_cy
, null as metric_1_ly
, sum
(
case
when (metric_id='703' and record_identifier=17)
or (metric_id='705' and record_identifier=777 )
or (metric_id='702' and record_identifier=123 )
or (metric_id='704' and record_identifier=17 )
or (metric_id='706' and record_identifier=99999997 )
or (metric_id='707' and record_identifier=99999996) then
sum_record_count
when metric_id not in ('702','703','704','705','706','707') then
null
else
0
end
) as metric_2_cy
, null as metric_2_ly
, null as metric_3_cy
, null as metric_3_ly
from
(
select col1, col2, col3, date_pk, colr, col5, colr_desc, col5_desc, record_identifier,
sum(nvl(record_count,0)) as sum_record_count
from txn
where col1=2
group by col1, col2, col3, date_pk, colr, col5, colr_desc, col5_desc, record_identifier
) pre_aggregate
cross join
(
select '703' as metric_id,'desc1' as en_metric_1_nm from dual
union all
select '702' as metric_id,'desc1' as en_metric_1_nm from dual
...
) lkp
group by col1, col2, col3, date_pk, colr, col5, colr_DESC, col5_DESC, metric_id, en_metric_1_nm;
答案 2 :(得分：0)
看起来您可以使选项二的七个单独查询在不同的CPU上并行运行。也许设置一些视图来解决结合结果的需要？
答案 3 :(得分：0)
为每个分区创建一个查询。由于分区键是聚合列之一，因此每个分区将生成单独的数据。
将单个语句分成多个较小的语句几乎总是效率低下。但是通过分区，整个表的数据只会被读取一次，即使它被查询了25次。此更改的效率应略低于原始方法，但应使用明显较少的临时表空间。除非分区严重偏斜。
begin
--Loop through all partitions.
for partition_names in
(
select partition_name
from user_tab_partitions
where table_name = 'TXN'
) loop
--Execute the statement.
execute immediate q'<
WITH IDQ_LKP AS
...
FROM TXN partition (>'||partition_names.partition_name||q'<),LKP
...
>';
--Normally commits should not be in DML loops, but a commit is required
--if the statement uses direct-path writes.
commit;
end loop;
end;
/
更新 - 单一查询方法及其可能有用的证据
每个分区上的查询可以合并为一个SQL语句。这应该仍然表现良好，并使用较少的临时表空间，虽然它将是一个helluva大型SQL语句。
基本理念是：
with lookup as ...
select txn partition (partition1), lookup ... union all
select txn partition (partition2), lookup ... union all
...
select txn partition (partition25), lookup ... union all
以下是示例表，示例数据和虚假统计信息：
create table txn(date_pk date, col1 number, col2 number, col3 number, colr number
,col5 number, colr_desc number, col5_desc number, record_count number
,record_identifier number)
partition by hash (col2)
(
partition p01,partition p02,partition p03,partition p04,partition p05,
partition p06,partition p07,partition p08,partition p09,partition p10,
partition p11,partition p12,partition p13,partition p14,partition p15,
partition p16,partition p17,partition p18,partition p19,partition p20,
partition p21,partition p22,partition p23,partition p24,partition p25
);
--A few fake rows just to create a column censity for GROUP BY
insert into txn
select sysdate, 2, level, level, level, level, level, level, level, level
from dual connect by level <= 100000;
begin
--Gather mostly for column density.
--Use GLOBAL because I don't know how to fake partition stats.
dbms_stats.gather_table_stats(user, 'txn', granularity => 'global');
--Fake 452M rows. This number will generate 262G of TempSpc.
--I can't reproduce it with 20G because I don't know the column densities.
dbms_stats.set_table_stats(user, 'TXN', numrows => 452000000);
end;
/
这是原始查询，通过一些修饰来减小它。它仍包含相同的列，条件和分组。请注意，优化器估计它将使用262GB的临时表空间，并且执行与您的执行非常相似。
explain plan for
WITH IDQ_LKP AS
(
SELECT '703' AS METRIC_ID,'desc1' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '702' AS METRIC_ID,'desc1' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '704' AS METRIC_ID,'% desc1' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '705' AS METRIC_ID,'desc2' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '706' AS METRIC_ID,'desc3' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '707' AS METRIC_ID,'desc5' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '701' AS METRIC_ID,'desc4' AS EN_METRIC_1_NM FROM DUAL
)
SELECT /*+ parallel(16) */
col1,col2,'Monthly Snapshots' Time_Rollup,col3,date_pk,colr,col5,colr_DESC,col5_DESC,metric_id,EN_METRIC_1_NM,NULL METRIC_1_LY,NULL METRIC_2_LY,NULL METRIC_3_CY,NULL METRIC_3_LY
,sum (CASE WHEN (metric_id='704' AND record_identifier=17 ) THEN nvl ( record_count,0 ) ELSE 0 END ) AS METRIC_1_CY
,sum (CASE WHEN (metric_id='703' AND record_identifier=17) THEN nvl ( record_count,0 ) ELSE 0 END ) AS METRIC_2_CY
FROM TXN,IDQ_LKP
WHERE col1=2
GROUP BY col1 , col2 , col3 , date_pk , colr , col5 , colr_DESC , col5_DESC, metric_id , EN_METRIC_1_NM;
select * from table(dbms_xplan.display);
Plan hash value: 2764457837
--------------------------------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes |TempSpc| Cost (%CPU)| Time | Pstart| Pstop | TQ |IN-OUT| PQ Distrib |
--------------------------------------------------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 3163M| 179G| | 67M (1)| 00:43:46 | | | | | |
| 1 | PX COORDINATOR | | | | | | | | | | | |
| 2 | PX SEND QC (RANDOM) | :TQ10002 | 3163M| 179G| | 67M (1)| 00:43:46 | | | Q1,02 | P->S | QC (RAND) |
| 3 | HASH GROUP BY | | 3163M| 179G| 262G| 67M (1)| 00:43:46 | | | Q1,02 | PCWP | |
| 4 | PX RECEIVE | | 3163M| 179G| | 67M (1)| 00:43:46 | | | Q1,02 | PCWP | |
| 5 | PX SEND HASH | :TQ10001 | 3163M| 179G| | 67M (1)| 00:43:46 | | | Q1,01 | P->P | HASH |
| 6 | HASH GROUP BY | | 3163M| 179G| 262G| 67M (1)| 00:43:46 | | | Q1,01 | PCWP | |
| 7 | MERGE JOIN CARTESIAN| | 3163M| 179G| | 488K (1)| 00:00:20 | | | Q1,01 | PCWP | |
| 8 | PX RECEIVE | | 7 | 70 | | 14 (0)| 00:00:01 | | | Q1,01 | PCWP | |
| 9 | PX SEND BROADCAST | :TQ10000 | 7 | 70 | | 14 (0)| 00:00:01 | | | Q1,00 | S->P | BROADCAST |
| 10 | PX SELECTOR | | | | | | | | | Q1,00 | SCWC | |
| 11 | VIEW | | 7 | 70 | | 14 (0)| 00:00:01 | | | Q1,00 | SCWC | |
| 12 | UNION-ALL | | | | | | | | | Q1,00 | SCWC | |
| 13 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | Q1,00 | SCWP | |
| 14 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | Q1,00 | SCWP | |
| 15 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | Q1,00 | SCWP | |
| 16 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | Q1,00 | SCWP | |
| 17 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | Q1,00 | SCWP | |
| 18 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | Q1,00 | SCWP | |
| 19 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | Q1,00 | SCWP | |
| 20 | BUFFER SORT | | 451M| 21G| | 67M (1)| 00:43:46 | | | Q1,01 | PCWP | |
| 21 | PX BLOCK ITERATOR | | 451M| 21G| | 570 (95)| 00:00:01 | 1 | 25 | Q1,01 | PCWC | |
|* 22 | TABLE ACCESS FULL| TXN | 451M| 21G| | 570 (95)| 00:00:01 | 1 | 25 | Q1,01 | PCWP | |
--------------------------------------------------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
22 - filter("COL1"=2)
Note
-----
- Degree of Parallelism is 16 because of hint
用多个txn,idq_lkp替换单个txn partition (pXX),idq_lkp会将最大临时表空间估计值从262G减少到10G。此示例仅包含25个分区中的2个，但添加更多分区不会增加所需的临时表空间。
explain plan for
WITH IDQ_LKP AS
(
SELECT '703' AS METRIC_ID,'desc1' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '702' AS METRIC_ID,'desc1' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '704' AS METRIC_ID,'% desc1' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '705' AS METRIC_ID,'desc2' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '706' AS METRIC_ID,'desc3' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '707' AS METRIC_ID,'desc5' AS EN_METRIC_1_NM FROM DUAL UNION ALL
SELECT '701' AS METRIC_ID,'desc4' AS EN_METRIC_1_NM FROM DUAL
)
SELECT /*+ parallel(16) */
col1,col2,'Monthly Snapshots' Time_Rollup,col3,date_pk,colr,col5,colr_DESC,col5_DESC,metric_id,EN_METRIC_1_NM,NULL METRIC_1_LY,NULL METRIC_2_LY,NULL METRIC_3_CY,NULL METRIC_3_LY
,sum (CASE WHEN (metric_id='704' AND record_identifier=17 ) THEN nvl ( record_count,0 ) ELSE 0 END ) AS METRIC_1_CY
,sum (CASE WHEN (metric_id='703' AND record_identifier=17) THEN nvl ( record_count,0 ) ELSE 0 END ) AS METRIC_2_CY
FROM TXN partition (p01),IDQ_LKP
WHERE col1=2
GROUP BY col1 , col2 , col3 , date_pk , colr , col5 , colr_DESC , col5_DESC, metric_id , EN_METRIC_1_NM
union all
SELECT /*+ parallel(16) */
col1,col2,'Monthly Snapshots' Time_Rollup,col3,date_pk,colr,col5,colr_DESC,col5_DESC,metric_id,EN_METRIC_1_NM,NULL METRIC_1_LY,NULL METRIC_2_LY,NULL METRIC_3_CY,NULL METRIC_3_LY
,sum (CASE WHEN (metric_id='704' AND record_identifier=17 ) THEN nvl ( record_count,0 ) ELSE 0 END ) AS METRIC_1_CY
,sum (CASE WHEN (metric_id='703' AND record_identifier=17) THEN nvl ( record_count,0 ) ELSE 0 END ) AS METRIC_2_CY
FROM TXN partition (p02),IDQ_LKP
WHERE col1=2
GROUP BY col1 , col2 , col3 , date_pk , colr , col5 , colr_DESC , col5_DESC, metric_id , EN_METRIC_1_NM;
select * from table(dbms_xplan.display);
Plan hash value: 260310120
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| Id | Operation | Name | Rows | Bytes |TempSpc| Cost (%CPU)| Time | Pstart| Pstop | TQ |IN-OUT| PQ Distrib |
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| 0 | SELECT STATEMENT | | 253M| 14G| | 3923K (51)| 00:02:34 | | | | | |
| 1 | TEMP TABLE TRANSFORMATION | | | | | | | | | | | |
| 2 | LOAD AS SELECT | SYS_TEMP_0FD9D66A0_D66798 | | | | | | | | | | |
| 3 | UNION-ALL | | | | | | | | | | | |
| 4 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | | | |
| 5 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | | | |
| 6 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | | | |
| 7 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | | | |
| 8 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | | | |
| 9 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | | | |
| 10 | FAST DUAL | | 1 | | | 2 (0)| 00:00:01 | | | | | |
| 11 | UNION-ALL | | | | | | | | | | | |
| 12 | PX COORDINATOR | | | | | | | | | | | |
| 13 | PX SEND QC (RANDOM) | :TQ10002 | 126M| 7362M| | 1961K (1)| 00:01:17 | | | Q1,02 | P->S | QC (RAND) |
| 14 | HASH GROUP BY | | 126M| 7362M| 10G| 1961K (1)| 00:01:17 | | | Q1,02 | PCWP | |
| 15 | PX RECEIVE | | 126M| 7362M| | 1961K (1)| 00:01:17 | | | Q1,02 | PCWP | |
| 16 | PX SEND HASH | :TQ10001 | 126M| 7362M| | 1961K (1)| 00:01:17 | | | Q1,01 | P->P | HASH |
| 17 | HASH GROUP BY | | 126M| 7362M| 10G| 1961K (1)| 00:01:17 | | | Q1,01 | PCWP | |
| 18 | MERGE JOIN CARTESIAN | | 126M| 7362M| | 19567 (1)| 00:00:01 | | | Q1,01 | PCWP | |
| 19 | PX RECEIVE | | 7 | 70 | | 2 (0)| 00:00:01 | | | Q1,01 | PCWP | |
| 20 | PX SEND BROADCAST | :TQ10000 | 7 | 70 | | 2 (0)| 00:00:01 | | | Q1,00 | P->P | BROADCAST |
| 21 | VIEW | | 7 | 70 | | 2 (0)| 00:00:01 | | | Q1,00 | PCWP | |
| 22 | PX BLOCK ITERATOR | | 7 | 70 | | 2 (0)| 00:00:01 | | | Q1,00 | PCWC | |
| 23 | TABLE ACCESS FULL| SYS_TEMP_0FD9D66A0_D66798 | 7 | 70 | | 2 (0)| 00:00:01 | | | Q1,00 | PCWP | |
| 24 | BUFFER SORT | | 18M| 879M| | 1961K (1)| 00:01:17 | | | Q1,01 | PCWP | |
| 25 | PX BLOCK ITERATOR | | 18M| 879M| | 23 (92)| 00:00:01 | 1 | 1 | Q1,01 | PCWC | |
|* 26 | TABLE ACCESS FULL | TXN | 18M| 879M| | 23 (92)| 00:00:01 | 1 | 1 | Q1,01 | PCWP | |
| 27 | PX COORDINATOR | | | | | | | | | | | |
| 28 | PX SEND QC (RANDOM) | :TQ20002 | 126M| 7362M| | 1961K (1)| 00:01:17 | | | Q2,02 | P->S | QC (RAND) |
| 29 | HASH GROUP BY | | 126M| 7362M| 10G| 1961K (1)| 00:01:17 | | | Q2,02 | PCWP | |
| 30 | PX RECEIVE | | 126M| 7362M| | 1961K (1)| 00:01:17 | | | Q2,02 | PCWP | |
| 31 | PX SEND HASH | :TQ20001 | 126M| 7362M| | 1961K (1)| 00:01:17 | | | Q2,01 | P->P | HASH |
| 32 | HASH GROUP BY | | 126M| 7362M| 10G| 1961K (1)| 00:01:17 | | | Q2,01 | PCWP | |
| 33 | MERGE JOIN CARTESIAN | | 126M| 7362M| | 19567 (1)| 00:00:01 | | | Q2,01 | PCWP | |
| 34 | PX RECEIVE | | 7 | 70 | | 2 (0)| 00:00:01 | | | Q2,01 | PCWP | |
| 35 | PX SEND BROADCAST | :TQ20000 | 7 | 70 | | 2 (0)| 00:00:01 | | | Q2,00 | P->P | BROADCAST |
| 36 | VIEW | | 7 | 70 | | 2 (0)| 00:00:01 | | | Q2,00 | PCWP | |
| 37 | PX BLOCK ITERATOR | | 7 | 70 | | 2 (0)| 00:00:01 | | | Q2,00 | PCWC | |
| 38 | TABLE ACCESS FULL| SYS_TEMP_0FD9D66A0_D66798 | 7 | 70 | | 2 (0)| 00:00:01 | | | Q2,00 | PCWP | |
| 39 | BUFFER SORT | | 18M| 879M| | 1961K (1)| 00:01:17 | | | Q2,01 | PCWP | |
| 40 | PX BLOCK ITERATOR | | 18M| 879M| | 23 (92)| 00:00:01 | 2 | 2 | Q2,01 | PCWC | |
|* 41 | TABLE ACCESS FULL | TXN | 18M| 879M| | 23 (92)| 00:00:01 | 2 | 2 | Q2,01 | PCWP | |
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Predicate Information (identified by operation id):
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26 - filter("COL1"=2)
41 - filter("COL1"=2)
Note
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- Degree of Parallelism is 16 because of hint