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Oracle 12CR2中表擴(kuò)展有什么用

發(fā)布時(shí)間:2021-11-10 14:42:59 來源:億速云 閱讀:118 作者:小新 欄目:關(guān)系型數(shù)據(jù)庫

小編給大家分享一下Oracle 12CR2中表擴(kuò)展有什么用,希望大家閱讀完這篇文章之后都有所收獲,下面讓我們一起去探討吧!

在表擴(kuò)展中,對于讀取一個(gè)分區(qū)表部分?jǐn)?shù)據(jù)時(shí)優(yōu)化器會(huì)生成使用索引的執(zhí)行計(jì)劃?;谒饕龍?zhí)行計(jì)劃可以提高性能,但索引維護(hù)會(huì)增加開鎖。在許多數(shù)據(jù)庫中,DML只影響小部分?jǐn)?shù)據(jù)。對于頻繁更新的表表擴(kuò)展使用基于索引的執(zhí)行計(jì)劃。你可以在以讀取為主的數(shù)據(jù)上創(chuàng)建一個(gè)索引,在以頻繁變化的數(shù)據(jù)上消除索引開銷。通過這種方式,表擴(kuò)展在避免索引維護(hù)的同時(shí)提高了性能。

表擴(kuò)展工作原理
表分區(qū)使用表擴(kuò)展成為可能。如果在一個(gè)分區(qū)表上創(chuàng)建一個(gè)本地索引,那么優(yōu)化器可能會(huì)標(biāo)記索引對于特定的分區(qū)不可使用。實(shí)際有些分區(qū)沒有創(chuàng)建索引。在表擴(kuò)展中,優(yōu)化器將查詢轉(zhuǎn)換為一個(gè)union all語句,讓一些子查詢訪問創(chuàng)建索引的分區(qū),一些子查詢訪問沒有創(chuàng)建索引的分區(qū)。優(yōu)化器可以為每個(gè)分區(qū)選擇最有效的訪問路徑,而不管它是否存在于查詢所要訪問的所有分區(qū)中。

優(yōu)化器不總是會(huì)選擇表擴(kuò)展
.表擴(kuò)展是基于成本
當(dāng)數(shù)據(jù)庫訪問擴(kuò)展表的每個(gè)分區(qū)只會(huì)跨越union all的所有分支一次,數(shù)據(jù)庫所連接的任何表都是在分支中被訪問。

.語義問題可能導(dǎo)致表擴(kuò)展無效
例如,一個(gè)表出現(xiàn)在一個(gè)外連接的右邊對于表擴(kuò)展來說是無效的。

可以使用expand_table hint來控制表擴(kuò)展。這個(gè)hint會(huì)覆蓋基于成本的決策,但不會(huì)覆蓋語義檢查。

表擴(kuò)展使用場景
優(yōu)化器基于查詢中出現(xiàn)的謂詞條件對每個(gè)表必須被訪問的分區(qū)保持跟蹤。分區(qū)裁剪能讓優(yōu)化器使用表擴(kuò)展來生成更有效的執(zhí)行計(jì)劃。

下面的例子假設(shè)滿足以下條件:
.想要對sh.sales表執(zhí)行星型查詢,表sh.sales是基于time_id列進(jìn)行范圍分區(qū)的一個(gè)分區(qū)表。

.想要禁用特定分區(qū)上的索引來查看表擴(kuò)展的優(yōu)點(diǎn)。

操作步驟如下:
1.以sh用戶登錄數(shù)據(jù)庫

[oracle@jytest1 ~]$ sqlplus sh/*****@jypdb
SQL*Plus: Release 12.2.0.1.0 Production on Wed Oct 31 18:09:54 2018
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Last Successful login time: Wed Oct 24 2018 17:00:11 +08:00
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
SQL>

2.執(zhí)行以下查詢

SQL> select *  from sales where time_id >= to_date('2000-01-01 00:00:00', 'syyyy-mm-dd hh34:mi:ss') and prod_id = 38;
...........
        38       2470 24-DEC-01             2        999             1       31.47
        38      13440 24-DEC-01             2        999             1       31.47
        38        490 28-DEC-01             2        999             1       31.47
        38       8406 28-DEC-01             2        999             1       31.47
        38       1466 31-DEC-01             3        351             1       31.47
        38       4340 31-DEC-01             3        351             1       31.47
        38      10658 31-DEC-01             3        351             1       31.47
        38      11390 31-DEC-01             3        351             1       31.47
        38      23226 31-DEC-01             3        351             1       31.47
4224 rows selected.

3.查詢執(zhí)行計(jì)劃

SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced allstats last runstats_last peeked_binds'));
SQL_ID  214qgysqqz0k8, child number 0
-------------------------------------
select *  from sales where time_id >= to_date('2000-01-01 00:00:00',
'syyyy-mm-dd hh34:mi:ss') and prod_id = 38
Plan hash value: 2342444420
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------
| Id  | Operation                                  | Name           | Starts | E-Rows |E-Bytes| Cost (%CPU)| E-Time   | Pstart| Pstop | A-Rows |   A-Time   | Buffers |
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                           |                |      1 |        |       |   224 (100)|          |       |       |   4224 |00:00:00.03 |     334 |
|   1 |  PARTITION RANGE ITERATOR                  |                |      1 |   5078 |   143K|   224   (0)| 00:00:01 |    13 |    28 |   4224 |00:00:00.03 |     334 |
|   2 |   TABLE ACCESS BY LOCAL INDEX ROWID BATCHED| SALES          |     16 |   5078 |   143K|   224   (0)| 00:00:01 |    13 |    28 |   4224 |00:00:00.02 |     334 |
|   3 |    BITMAP CONVERSION TO ROWIDS             |                |      8 |        |       |            |          |       |       |   4224 |00:00:00.01 |      24 |
|*  4 |     BITMAP INDEX SINGLE VALUE              | SALES_PROD_BIX |      8 |        |       |            |          |    13 |    28 |      8 |00:00:00.01 |      24 |
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------
Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------
   1 - SEL$1
   2 - SEL$1 / SALES@SEL$1
Outline Data
-------------
  /*+
      BEGIN_OUTLINE_DATA
      IGNORE_OPTIM_EMBEDDED_HINTS
      OPTIMIZER_FEATURES_ENABLE('12.2.0.1')
      DB_VERSION('12.2.0.1')
      ALL_ROWS
      NO_PARALLEL
      OUTLINE_LEAF(@"SEL$1")
      BITMAP_TREE(@"SEL$1" "SALES"@"SEL$1" AND(("SALES"."PROD_ID")))
      BATCH_TABLE_ACCESS_BY_ROWID(@"SEL$1" "SALES"@"SEL$1")
      END_OUTLINE_DATA
  */
Predicate Information (identified by operation id):
---------------------------------------------------
   4 - access("PROD_ID"=38)
Column Projection Information (identified by operation id):
-----------------------------------------------------------
   1 - "PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   2 - "PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   3 - "SALES".ROWID[ROWID,10], "PROD_ID"[NUMBER,22]
   4 - STRDEF[BM VAR, 10], STRDEF[BM VAR, 10], STRDEF[BM VAR, 7920], "PROD_ID"[NUMBER,22]
Note
-----
   - automatic DOP: Computed Degree of Parallelism is 1 because of parallel threshold
58 rows selected.

在執(zhí)行計(jì)劃中的Pstart與Pstop列,顯示了優(yōu)化器判斷只需要訪問表的13到28分區(qū)。在優(yōu)化器已經(jīng)判斷了被訪問的分區(qū)之后,它將考慮所有這些分區(qū)上可以使用的索引。在上面的執(zhí)行計(jì)劃中,優(yōu)化器選擇使用sales_prod_bix位圖索引

4.禁用sales表中sales_1995分區(qū)上的索引;

SQL> alter index sales_prod_bix modify partition sales_1995 unusable;
Index altered.

5.再次執(zhí)行之前的查詢語句,然后顯示執(zhí)行計(jì)劃,可以看到執(zhí)行計(jì)劃變成了由兩個(gè)子查詢組成的union all語句,第一個(gè)子查詢還是對13-28分區(qū)使用索引,第二個(gè)子查詢步驟對應(yīng)的Pstart與Pstop為invalid,id=11的過濾條件為"PROD_ID"=38,id=9的過濾條件為"SALES"."TIME_ID"=TO_DATE(' 2000-01-01 00:00:00', 'syyyy-mm-dd hh34:mi:ss')))這個(gè)過濾條件是為否的,所以過濾后的記錄為0,從對應(yīng)的A-Rows列也可以看到記錄為0

SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced allstats last runstats_last peeked_binds'));
SQL_ID  214qgysqqz0k8, child number 0
-------------------------------------
select *  from sales where time_id >= to_date('2000-01-01 00:00:00',
'syyyy-mm-dd hh34:mi:ss') and prod_id = 38
Plan hash value: 238952339
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| Id  | Operation                                     | Name           | Starts | E-Rows |E-Bytes| Cost (%CPU)| E-Time   | Pstart| Pstop | A-Rows |   A-Time   | Buffers |
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                              |                |      1 |        |       |   224 (100)|          |       |       |   4224 |00:00:00.05 |     334 |
|   1 |  VIEW                                         | VW_TE_2        |      1 |   5079 |   431K|   224   (0)| 00:00:01 |       |       |   4224 |00:00:00.05 |     334 |
|   2 |   UNION-ALL                                   |                |      1 |        |       |            |          |       |       |   4224 |00:00:00.05 |     334 |
|   3 |    PARTITION RANGE ITERATOR                   |                |      1 |   5078 |   143K|   224   (0)| 00:00:01 |    13 |    28 |   4224 |00:00:00.03 |     334 |
|   4 |     TABLE ACCESS BY LOCAL INDEX ROWID BATCHED | SALES          |     16 |   5078 |   143K|   224   (0)| 00:00:01 |    13 |    28 |   4224 |00:00:00.02 |     334 |
|   5 |      BITMAP CONVERSION TO ROWIDS              |                |      8 |        |       |            |          |       |       |   4224 |00:00:00.01 |      24 |
|*  6 |       BITMAP INDEX SINGLE VALUE               | SALES_PROD_BIX |      8 |        |       |            |          |    13 |    28 |      8 |00:00:00.01 |      24 |
|*  7 |    FILTER                                     |                |      1 |        |       |            |          |       |       |      0 |00:00:00.01 |       0 |
|   8 |     PARTITION RANGE EMPTY                     |                |      0 |      1 |    29 |     1   (0)| 00:00:01 |INVALID|INVALID|      0 |00:00:00.01 |       0 |
|*  9 |      TABLE ACCESS BY LOCAL INDEX ROWID BATCHED| SALES          |      0 |      1 |    29 |     1   (0)| 00:00:01 |INVALID|INVALID|      0 |00:00:00.01 |       0 |
|  10 |       BITMAP CONVERSION TO ROWIDS             |                |      0 |        |       |            |          |       |       |      0 |00:00:00.01 |       0 |
|* 11 |        BITMAP INDEX SINGLE VALUE              | SALES_PROD_BIX |      0 |        |       |            |          |INVALID|INVALID|      0 |00:00:00.01 |       0 |
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------
   1 - SET$D0A14387   / VW_TE_2@SEL$0A5B0FFE
   2 - SET$D0A14387
   3 - SET$D0A14387_1
   4 - SET$D0A14387_1 / SALES@SEL$1
   7 - SET$D0A14387_2
   9 - SET$D0A14387_2 / SALES@SEL$1
Outline Data
-------------
  /*+
      BEGIN_OUTLINE_DATA
      IGNORE_OPTIM_EMBEDDED_HINTS
      OPTIMIZER_FEATURES_ENABLE('12.2.0.1')
      DB_VERSION('12.2.0.1')
      ALL_ROWS
      NO_PARALLEL
      OUTLINE_LEAF(@"SET$D0A14387_2")
      OUTLINE_LEAF(@"SET$D0A14387_1")
      OUTLINE_LEAF(@"SET$D0A14387")
      EXPAND_TABLE(@"SEL$1" "SALES"@"SEL$1")
      OUTLINE_LEAF(@"SEL$0A5B0FFE")
      OUTLINE(@"SET$D0A14387")
      EXPAND_TABLE(@"SEL$1" "SALES"@"SEL$1")
      OUTLINE(@"SEL$1")
      NO_ACCESS(@"SEL$0A5B0FFE" "VW_TE_2"@"SEL$0A5B0FFE")
      BITMAP_TREE(@"SET$D0A14387_1" "SALES"@"SEL$1" AND(("SALES"."PROD_ID")))
      BATCH_TABLE_ACCESS_BY_ROWID(@"SET$D0A14387_1" "SALES"@"SEL$1")
      BITMAP_TREE(@"SET$D0A14387_2" "SALES"@"SEL$1" AND(("SALES"."PROD_ID")))
      BATCH_TABLE_ACCESS_BY_ROWID(@"SET$D0A14387_2" "SALES"@"SEL$1")
      END_OUTLINE_DATA
  */
Predicate Information (identified by operation id):
---------------------------------------------------
   6 - access("PROD_ID"=38)
   7 - filter(NULL IS NOT NULL)
   9 - filter(("SALES"."TIME_ID"=TO_DATE(' 2000-01-01 00:00:00', 'syyyy-mm-dd
              hh34:mi:ss')))
  11 - access("PROD_ID"=38)
Column Projection Information (identified by operation id):
-----------------------------------------------------------
   1 - "ITEM_1"[NUMBER,22], "ITEM_2"[NUMBER,22], "ITEM_3"[DATE,7], "ITEM_4"[NUMBER,22], "ITEM_5"[NUMBER,22], "ITEM_6"[NUMBER,22], "ITEM_7"[NUMBER,22]
   2 - STRDEF[22], STRDEF[22], STRDEF[7], STRDEF[22], STRDEF[22], STRDEF[22], STRDEF[22]
   3 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   4 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   5 - "SALES".ROWID[ROWID,10], "SALES"."PROD_ID"[NUMBER,22]
   6 - STRDEF[BM VAR, 10], STRDEF[BM VAR, 10], STRDEF[BM VAR, 7920], "SALES"."PROD_ID"[NUMBER,22]
   7 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   8 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   9 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
  10 - "SALES".ROWID[ROWID,10], "SALES"."PROD_ID"[NUMBER,22]
  11 - STRDEF[BM VAR, 10], STRDEF[BM VAR, 10], STRDEF[BM VAR, 7920], "SALES"."PROD_ID"[NUMBER,22]
Note
-----
   - automatic DOP: Computed Degree of Parallelism is 1 because of parallel threshold
93 rows selected.

6.禁用分區(qū)28上的索引(sales_q4_2003),它是查詢需要訪問的一個(gè)分區(qū):

SQL> alter index sales_prod_bix modify partition sales_q4_2003 unusable;
Index altered.
SQL> alter index sales_time_bix modify partition sales_q4_2003 unusable;
Index altered.

通過禁用查詢需要訪問分區(qū)上的索引,查詢將不能再使用這些索引。

7.再次執(zhí)行查詢語句,其執(zhí)行計(jì)劃如下,執(zhí)行計(jì)劃變成了由三個(gè)子查詢組成的union all語句,相比之前查詢多的第三個(gè)子查詢對表sales的第28個(gè)分區(qū)執(zhí)行全表掃描,這里沒有索引可用,因?yàn)橐呀?jīng)禁用28分區(qū)上的索引了。

SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced allstats last runstats_last peeked_binds'));
SQL_ID  214qgysqqz0k8, child number 0
-------------------------------------
select *  from sales where time_id >= to_date('2000-01-01 00:00:00',
'syyyy-mm-dd hh34:mi:ss') and prod_id = 38
Plan hash value: 3857158179
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| Id  | Operation                                     | Name           | Starts | E-Rows |E-Bytes| Cost (%CPU)| E-Time   | Pstart| Pstop | A-Rows |   A-Time   | Buffers | Reads  |
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                              |                |      1 |        |       |   225 (100)|          |       |       |   4224 |00:00:00.20 |     334 |     44 |
|   1 |  VIEW                                         | VW_TE_2        |      1 |   5080 |   431K|   225   (0)| 00:00:01 |       |       |   4224 |00:00:00.20 |     334 |     44 |
|   2 |   UNION-ALL                                   |                |      1 |        |       |            |          |       |       |   4224 |00:00:00.19 |     334 |     44 |
|   3 |    PARTITION RANGE ITERATOR                   |                |      1 |   5078 |   143K|   223   (0)| 00:00:01 |    13 |    27 |   4224 |00:00:00.17 |     334 |     44 |
|   4 |     TABLE ACCESS BY LOCAL INDEX ROWID BATCHED | SALES          |     15 |   5078 |   143K|   223   (0)| 00:00:01 |    13 |    27 |   4224 |00:00:00.16 |     334 |     44 |
|   5 |      BITMAP CONVERSION TO ROWIDS              |                |      8 |        |       |            |          |       |       |   4224 |00:00:00.03 |      24 |     16 |
|*  6 |       BITMAP INDEX SINGLE VALUE               | SALES_PROD_BIX |      8 |        |       |            |          |    13 |    27 |      8 |00:00:00.03 |      24 |     16 |
|*  7 |    FILTER                                     |                |      1 |        |       |            |          |       |       |      0 |00:00:00.01 |       0 |      0 |
|   8 |     PARTITION RANGE EMPTY                     |                |      0 |      1 |    29 |     1   (0)| 00:00:01 |INVALID|INVALID|      0 |00:00:00.01 |       0 |      0 |
|*  9 |      TABLE ACCESS BY LOCAL INDEX ROWID BATCHED| SALES          |      0 |      1 |    29 |     1   (0)| 00:00:01 |INVALID|INVALID|      0 |00:00:00.01 |       0 |      0 |
|  10 |       BITMAP CONVERSION TO ROWIDS             |                |      0 |        |       |            |          |       |       |      0 |00:00:00.01 |       0 |      0 |
|* 11 |        BITMAP INDEX SINGLE VALUE              | SALES_PROD_BIX |      0 |        |       |            |          |INVALID|INVALID|      0 |00:00:00.01 |       0 |      0 |
|  12 |    PARTITION RANGE SINGLE                     |                |      1 |      1 |    87 |     2   (0)| 00:00:01 |    28 |    28 |      0 |00:00:00.01 |       0 |      0 |
|* 13 |     TABLE ACCESS FULL                         | SALES          |      1 |      1 |    87 |     2   (0)| 00:00:01 |    28 |    28 |      0 |00:00:00.01 |       0 |      0 |
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------
   1 - SET$D0A14387   / VW_TE_2@SEL$0A5B0FFE
   2 - SET$D0A14387
   3 - SET$D0A14387_1
   4 - SET$D0A14387_1 / SALES@SEL$1
   7 - SET$D0A14387_2
   9 - SET$D0A14387_2 / SALES@SEL$1
  12 - SET$D0A14387_3
  13 - SET$D0A14387_3 / SALES@SEL$1
Outline Data
-------------
  /*+
      BEGIN_OUTLINE_DATA
      IGNORE_OPTIM_EMBEDDED_HINTS
      OPTIMIZER_FEATURES_ENABLE('12.2.0.1')
      DB_VERSION('12.2.0.1')
      ALL_ROWS
      NO_PARALLEL
      OUTLINE_LEAF(@"SET$D0A14387_3")
      OUTLINE_LEAF(@"SET$D0A14387_2")
      OUTLINE_LEAF(@"SET$D0A14387_1")
      OUTLINE_LEAF(@"SET$D0A14387")
      EXPAND_TABLE(@"SEL$1" "SALES"@"SEL$1")
      OUTLINE_LEAF(@"SEL$0A5B0FFE")
      OUTLINE(@"SET$D0A14387")
      EXPAND_TABLE(@"SEL$1" "SALES"@"SEL$1")
      OUTLINE(@"SEL$1")
      NO_ACCESS(@"SEL$0A5B0FFE" "VW_TE_2"@"SEL$0A5B0FFE")
      BITMAP_TREE(@"SET$D0A14387_1" "SALES"@"SEL$1" AND(("SALES"."PROD_ID")))
      BATCH_TABLE_ACCESS_BY_ROWID(@"SET$D0A14387_1" "SALES"@"SEL$1")
      BITMAP_TREE(@"SET$D0A14387_2" "SALES"@"SEL$1" AND(("SALES"."PROD_ID")))
      BATCH_TABLE_ACCESS_BY_ROWID(@"SET$D0A14387_2" "SALES"@"SEL$1")
      FULL(@"SET$D0A14387_3" "SALES"@"SEL$1")
      END_OUTLINE_DATA
  */
Predicate Information (identified by operation id):
---------------------------------------------------
   6 - access("PROD_ID"=38)
   7 - filter(NULL IS NOT NULL)
   9 - filter(("SALES"."TIME_ID"=TO_DATE(' 2000-01-01 00:00:00', 'syyyy-mm-dd hh34:mi:ss')))
  11 - access("PROD_ID"=38)
  13 - filter("PROD_ID"=38)
Column Projection Information (identified by operation id):
-----------------------------------------------------------
   1 - "ITEM_1"[NUMBER,22], "ITEM_2"[NUMBER,22], "ITEM_3"[DATE,7], "ITEM_4"[NUMBER,22], "ITEM_5"[NUMBER,22], "ITEM_6"[NUMBER,22], "ITEM_7"[NUMBER,22]
   2 - STRDEF[22], STRDEF[22], STRDEF[7], STRDEF[22], STRDEF[22], STRDEF[22], STRDEF[22]
   3 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   4 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   5 - "SALES".ROWID[ROWID,10], "SALES"."PROD_ID"[NUMBER,22]
   6 - STRDEF[BM VAR, 10], STRDEF[BM VAR, 10], STRDEF[BM VAR, 7920], "SALES"."PROD_ID"[NUMBER,22]
   7 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   8 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
   9 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
  10 - "SALES".ROWID[ROWID,10], "SALES"."PROD_ID"[NUMBER,22]
  11 - STRDEF[BM VAR, 10], STRDEF[BM VAR, 10], STRDEF[BM VAR, 7920], "SALES"."PROD_ID"[NUMBER,22]
  12 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
  13 - "SALES"."PROD_ID"[NUMBER,22], "SALES"."CUST_ID"[NUMBER,22], "SALES"."TIME_ID"[DATE,7], "SALES"."CHANNEL_ID"[NUMBER,22], "SALES"."PROMO_ID"[NUMBER,22],
       "SALES"."QUANTITY_SOLD"[NUMBER,22], "SALES"."AMOUNT_SOLD"[NUMBER,22]
Note
-----
   - automatic DOP: Computed Degree of Parallelism is 1 because of parallel threshold
103 rows selected.

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