A look at the partitioning facilities all the way up 11g

1. NOTE
itty bitty fonts in this
presentation
SQL> exec sample_font
Can you read this ?
1

2. Connor McDonald
OracleDBA
co.uk
2

3. 3

4. bio slide
4

5. Connor McDonald

6. 6

7. why ?
...now
7

8. version 8.0
8

9. 9

10. 10

11. a personal history
11

12. 80's
12

13. 13

14. 14

15. Walker Interactive
15

16. Jeff Walker...
16

17. 20G
17

19. $200
per gigabyte
per month
19

20. Storage
is
expensive
20

21. Archive
21

22. 22

23. 90's
23

24. 24

25. JBOD
25

26. Storage
is
cheap !
26

27. Archive
27

28. Archive
28

29. 1992 1996 1999

30. 30

31. 00's
31

32. disk is even cheaper....
32

33. 33

34. ....but
34

36. keep everything !
36

37. JBOD
37

38. 38

39. HBA
Infiniband
Filer
Cache
Fibre Channel
etc
39

40. Storage
is
cheap !
40

41. Storage Storage
is is
expensive cheap !
41

42. CEO
42

43. brings us to today...
43

44. ILM
44

45. Information
Lifecycle
Management
45

46. keep everything .... cheaply
46

47. put the new stuff on good storage
keep everything .... cheaply
put the old stuff on crappy storage
47

48. split stuff up
48

49. 49

50. basics
50

51. range partitioning
since 8.0
51

52. SALES
2009 2010 2011 2012
52

53. provocative statement
53

54. "all applications are (time)
windows on data"
http://thehelsinkideclaration.blogspot.com/
54

55. corollary:
everyone can benefit
from range partitions
55

56. time the most common
56

57. SQL> create table DEMO
2 ( tstamp timestamp(6) not null,
3 empno number(10) not null,
4 ename varchar2(10) not null,
5 deptno varchar2(10) not null
6 )
7 PARTITION BY RANGE (TSTAMP)
8 (
9 PARTITION p01 VALUES LESS THAN
10 (TIMESTAMP' 2010-01-01 00:00:00'),
11 PARTITION p02 VALUES LESS THAN
12 (TIMESTAMP' 2010-02-01 00:00:00'),
13 PARTITION p03 VALUES LESS THAN
14 (TIMESTAMP' 2010-03-01 00:00:00'),
...
...
25 PARTITION p13 VALUES LESS THAN
26 (TIMESTAMP' 2011-01-01 00:00:00')
27 );
Table created.
57

58. SQL> select partition_name pname,
2 partition_position pos,
3 high_value
4 from USER_TAB_PARTITIONS
5 where table_name = 'DEMO';
PNAME POS HIGH_VALUE
----- ---------- -------------------------------
P01 1 TIMESTAMP' 2010-01-01 00:00:00'
P02 2 TIMESTAMP' 2010-02-01 00:00:00'
P03 3 TIMESTAMP' 2010-03-01 00:00:00'
P04 4 TIMESTAMP' 2010-04-01 00:00:00'
P05 5 TIMESTAMP' 2010-05-01 00:00:00'
P06 6 TIMESTAMP' 2010-06-01 00:00:00'
P07 7 TIMESTAMP' 2010-07-01 00:00:00'
P08 8 TIMESTAMP' 2010-08-01 00:00:00'
P09 9 TIMESTAMP' 2010-09-01 00:00:00'
P10 10 TIMESTAMP' 2010-10-01 00:00:00'
P11 11 TIMESTAMP' 2010-11-01 00:00:00'
P12 12 TIMESTAMP' 2010-12-01 00:00:00'
P13 13 TIMESTAMP' 2011-01-01 00:00:00'
58

59. range partition boundaries
59

60. split by upper bound
60

61. P02 >= 2010-01-01
P02 < 2010-02-01
PARTITION p01 VALUES LESS THAN
(TIMESTAMP' 2010-01-01 00:00:00'),
PARTITION p02 VALUES LESS THAN
(TIMESTAMP' 2010-02-01 00:00:00'),
January not February
61

62. possible benefits
62

63. performance
63

64. partition pruning
64

65. SQL> set autotrace traceonly explain
SQL> select * from DEMO
2 where TSTAMP = to_date('11-JUN-2010');
---------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
---------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | | |
| 1 | PARTITION RANGE SINGLE| | 1 | 7 | 7 |
|* 2 | TABLE ACCESS FULL | DEMO | 1 | 7 | 7 |
---------------------------------------------------------------
65

66. SQL> select partition_name pname,
2 partition_position pos,
3 high_value
4 from user_tab_partitions
5 where table_name = 'DEMO';
PNAME POS HIGH_VALUE
----- ---------- -------------------------------
P01 1 TIMESTAMP' 2010-01-01 00:00:00'
P02 2 TIMESTAMP' 2010-02-01 00:00:00'
P03 3 TIMESTAMP' 2010-03-01 00:00:00'
P04 4 TIMESTAMP' 2010-04-01 00:00:00'
P05 5 TIMESTAMP' 2010-05-01 00:00:00'
P06 6 TIMESTAMP' 2010-06-01 00:00:00'
P07 7 TIMESTAMP' 2010-07-01 00:00:00'
P08 8 TIMESTAMP' 2010-08-01 00:00:00'
P09 9 TIMESTAMP' 2010-09-01 00:00:00'
P10 10 TIMESTAMP' 2010-10-01 00:00:00'
P11 11 TIMESTAMP' 2010-11-01 00:00:00'
P12 12 TIMESTAMP' 2010-12-01 00:00:00'
P13 13 TIMESTAMP' 2011-01-01 00:00:00'
66

67. more later...
67

68. dbms_xplan
68

69. SQL> explain plan for select ....
SQL> select *
2 from table(dbms_xplan.display)
69

70. SQL> select *
2 from table(
3 dbms_xplan.display(
4 format=>'PARTITION -COST -BYTES'));
70

71. SQL> select *
2 from table(dbms_xplan.display_awr(...))
71

72. SQL> select ...
SQL> select *
2 from table(dbms_xplan.display_cursor)
72

73. SQL> select *
2 from table(dbms_xplan.display_plan_baseline)
73

74. back to range partitioning
74

75. add / drop
move
cache control
maintenance
rebuild
backup / read-only
compress
75

76. partition loss
availability
recovery
a little dubious....
76

77. multi-column range
77

78. SQL> create table SALES_DATA
2 ( yyyy number(4) not null,
3 mm number(2) not null,
4 sales_id varchar2(10) not null,
5 amount number(10)
6 )
7 PARTITION BY RANGE (yyyy, mm)
8 (
9 PARTITION p01 VALUES LESS THAN (2010,02),
10 PARTITION p02 VALUES LESS THAN (2010,03),
11 PARTITION p03 VALUES LESS THAN (2010,04)
...
...
22 )
23 /
Table created.
78

79. tiebreaker
79

80. not multi dimension
80

81. SQL> create table MOBILE_PHONE
2 ( start_day date not null,
3 end_day date not null,
4 account_id varchar2(10) not null,
5 calls number(10)
6 )
7 PARTITION BY RANGE (start_day, end_day)
8 (
9 PARTITION p01 VALUES LESS THAN
10 ('01-FEB-2010','01-FEB-2010'),
11 PARTITION p02 VALUES LESS THAN
12 ('01-MAR-2010','01-MAR-2010'),
13 PARTITION p03 VALUES LESS THAN
14 ('01-APR-2010','01-APR-2010')
15 )
16 /
Table created.
81

82. SQL> select sum(calls)
2 from MOBILE_PHONE
3 where START_DAY= '12-FEB-2010';
----------------------------------------------------------------
| Id | Operation | Name | Pstart| Pstop |
----------------------------------------------------------------
| 0 | SELECT STATEMENT | | | |
| 1 | SORT AGGREGATE | | | |
| 2 | PARTITION RANGE SINGLE| | 3 | 3 |
|* 3 | TABLE ACCESS FULL | MOBILE_PHONE | 3 | 3 |
----------------------------------------------------------------
82

83. SQL> select sum(calls)
2 from MOBILE_PHONE
3 where END_DAY= '12-FEB-2010';
----------------------------------------------------------------------
| Id | Operation | Name | Pstart| Pstop |
----------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | |
| 1 | SORT AGGREGATE | | | |
| 2 | PARTITION RANGE ALL | | 1 | 3 |
|* 3 | TABLE ACCESS FULL | MOBILE_PHONE | 1 | 3 |
----------------------------------------------------------------------
83

84. 9 PARTITION p01 VALUES LESS THAN
10 ('01-FEB-2010','01-FEB-2010'),
11 PARTITION p02 VALUES LESS THAN
12 ('01-MAR-2010','01-MAR-2010'),
13 PARTITION p03 VALUES LESS THAN
14 ('01-APR-2010','01-APR-2010')
SQL> insert into MOBILE_PHONE
2 values ('07-FEB-2010','12-FEB-2010');
SQL> insert into MOBILE_PHONE
2 values ('23-JAN-2010','12-FEB-2010');
SQL> insert into MOBILE_PHONE
2 values ('17-MAR-2010','12-FEB-2010');
84

85. better in 11g
85

86. SQL> select sum(calls)
2 from MOBILE_PHONE
3 where END_DAY= '12-FEB-2010';
----------------------------------------------------------------------
| Id | Operation | Name | Pstart| Pstop |
----------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | |
| 1 | SORT AGGREGATE | | | |
| 2 | PARTITION RANGE MULTI-COLUMN| |KEY(MC)|KEY(MC)|
|* 3 | TABLE ACCESS FULL | MOBILE_PHONE |KEY(MC)|KEY(MC)|
----------------------------------------------------------------------
86

87. hash partitioning
since 8.1
87

88. big stuff is a pain
88

89. "metapoor"
89

92. possible benefits
92

93. manageability
93

94. 94

95. move
backup
etc
95

96. insertion
performance
96

97. "buffer busy waits"
97

98. "enq: HW - contention"
98

99. "read by other session"
99

100. 100

101. less relevant nowadays
for tables
101

102. ASSM
102

103. automatic
segment
space
management
103

104. SQL> CREATE TABLESPACE DEMO
2 DATAFILE '...' SIZE 20G
3 EXTENT MANAGEMENT LOCAL
4 SEGMENT SPACE MANAGEMENT AUTO;
104

105. 105

106. ...but still very important
see later
106

107. SQL> create table T
2 ( x number(10) )
3 partition by hash ( x )
4 partitions 8
5 /
Table created.
107

108. even spread of values
108

109. SQL> create table T
2 ( x number(10) )
3 partition by hash ( x )
4 partitions 8
5 /
Table created.
1,2,3,4 .... 100000
SQL> insert into T
2 select level
3 from dual connect by level <= 100000
4 /
100000 rows created.
109

110. SQL> select DBMS_ROWID.ROWID_OBJECT(rowid) ptn,
2 count(*)
3 from T
4 group by DBMS_ROWID.ROWID_OBJECT(rowid);
PTN COUNT(*)
---------- ----------
72166 12381
72167 12628
72161 12603
72162 12574
72163 12581
72168 12382
72164 12508
72165 12342
110

111. predicting hash target
111

112. SQL> select dbms_rowid.ROWID_OBJECT(rowid) ptn,
2 count(*)
3 from T
SQL> select ora_hash(x,7), count(*)
4 2 from t dbms_rowid.ROWID_OBJECT(rowid)
group by
5 3 group by ora_hash(x,7)
order by 2;
4 order by 2;
PTN COUNT(*)
---------- ----------
ORA_HASH(X,7) COUNT(*)
------------- 12342
73535 ----------
73536 4 12381 12342
73538 5 12382 12381 remember these
73534 7 12508 12382
73532 3 12574 12508
73533 1 12581 12574
73531 2 12603 12581
73537 0 12628 12603
6 12628
112

113. the power of 2 rule
113

114. SQL> create table T
2 ( x number(10) )
3 partition by hash ( x )
4 partitions 4 | 8 | 16 | 32 ...
5 /
Table created.
114

115. SQL> select DBMS_ROWID.ROWID_OBJECT(rowid) ptn,
2 count(*)
3 from T
4 group by DBMS_ROWID.ROWID_OBJECT(rowid);
PTN COUNT(*)
---------- ----------
72166 12381
72167 12628
72161 12603
72162 12574
72163 12581
72168 12382
72164 12508
72165 12342
115

116. SQL> create table T
2 ( x number(10) )
3 partition by hash ( x )
4 partitions 5
5 /
Table created.
SQL> insert into T
2 select level
3 from dual connect by level <= 100000
4 /
100000 rows created.
116

117. SQL> select DBMS_ROWID.ROWID_OBJECT(rowid) ptn,
2 count(*)
3 from T
4 group by DBMS_ROWID.ROWID_OBJECT(rowid);
PTN COUNT(*)
---------- ----------
72174 12342
72172 25209
72171 24955
72173 24890
72170 12603
117

118. why ?
118

119. deliberately
for maintenance...
119

120. Task:
from 5 to 8 partitions
120

121. "classical" redistribution
121

122. "every" row moves
122

123. SQL> select count(*)
2 from T
3 where ora_hash(x,4) != ora_hash(x,7);
COUNT(*)
----------
87564
123

124. "smart" redistribution
124

125. SQL> select DBMS_ROWID.ROWID_OBJECT(rowid) ptn,
2 count(*)
3 from T
4 group by DBMS_ROWID.ROWID_OBJECT(rowid);
PTN COUNT(*)
---------- ----------
72174 12342
72172 25209
72171 24955
72173 24890 pick one
72170 12603
5 rows selected.
125

126. SQL> alter table T add partition;
Table altered.
SQL> select dbms_rowid.ROWID_OBJECT(rowid) ptn,
2 count(*)
3 from T
4 group by dbms_rowid.ROWID_OBJECT(rowid);
PTN COUNT(*)
---------- ----------
73515 25209
73516 24890
73517 12342
73519 12381
73518 12574
73513 12603
126

127. SQL> alter table T add partition;
Table altered.
SQL> select dbms_rowid.ROWID_OBJECT(rowid) ptn,
2 count(*)
3 from T
4 group by dbms_rowid.ROWID_OBJECT(rowid);
PTN COUNT(*)
---------- ----------
73516 24890
73517 12342
73519 12381
73518 12574
73521 12628
73520 12581
73513 12603
127

128. SQL> alter table T add partition;
Table altered.
SQL> select dbms_rowid.ROWID_OBJECT(rowid) ptn,
2 count(*)
3 from T
4 group by dbms_rowid.ROWID_OBJECT(rowid);
PTN COUNT(*)
---------- ----------
73517 12342
73523 12382
73522 12508
73519 12381
73518 12574
73521 12628
73520 12581
73513 12603
128

129. only 1 partition "effort"
129

130. same for coalesce partition
130

131. handling a small number of values
131

132. SQL> create table ...
...
20 values less than ('WB'),
21 values less than ('QLE'),
22 values less than ('SB'),
23 values less than ('VID'),
range fiddly....
132

133. SQL> select state, ora_hash(state,7) hash
2 from AUST;
STATE HASH
----- ----
WA 2
SA 5
NSW 3
VIC 5
hash ... poor distribution
133

134. list
version 9
134

135. SQL> create table SALES_DATA
2 ( sales_id varchar2(10) not null,
3 location varchar2(3) not null,
4 amount number(10)
5 )
6 PARTITION BY LIST (location)
7 (
8 PARTITION NSW VALUES ('NSW'),
9 PARTITION WA VALUES ('WA'),
10 PARTITION QLD VALUES ('QLD'),
11 PARTITION SA VALUES ('SA'),
12 PARTITION VIC VALUES ('VIC'),
13 PARTITION TERR VALUES ('ACT','NT'),
14 PARTITION DREGS VALUES (DEFAULT)
15 )
18 /
Table created.
135

136. think carefully on DEFAULT
add versus split
136

137. sometimes one level is not enough
137

138. 138

139. 139

140. ranges unevenly distributed
140

141. deletion of older data
2009
2010
2011 2012
141

142. composite partitions
142

143. composite (range + hash)
since 8.1
143

144. SQL> create table COMP
2 ( tstamp timestamp(6) not null,
3 empno number(10) not null,
4 ename varchar2(10) not null,
5 deptno varchar2(10) not null
6 )
7 PARTITION BY RANGE (TSTAMP)
8 SUBPARTITION BY LIST (deptno)
9 (
10 PARTITION p01 VALUES LESS THAN
11 (TIMESTAMP' 2010-01-01 00:00:00')
12 (SUBPARTITION p01_d1 VALUES (1),
13 SUBPARTITION p01_d2 VALUES (2),
14 SUBPARTITION p01_d3 VALUES (3),
15 SUBPARTITION p01_d4 VALUES (4)),
16 PARTITION p02 VALUES LESS THAN
17 (TIMESTAMP' 2010-02-01 00:00:00')
18 (SUBPARTITION p02_d1 VALUES (1),
19 SUBPARTITION p02_d2 VALUES (2),
20 SUBPARTITION p02_d3 VALUES (3),
21 SUBPARTITION p02_d4 VALUES (4)),
..... 144

145. 30 PARTITION p11 VALUES LESS THAN
31 (TIMESTAMP' 2010-11-01 00:00:00')
32 (SUBPARTITION p01_d1 VALUES (1,2),
33 SUBPARTITION p01_d2 VALUES (3,4),
34 PARTITION p12 VALUES LESS THAN
35 (TIMESTAMP' 2010-12-01 00:00:00')
36 PARTITION p13 VALUES LESS THAN
37 (TIMESTAMP' 2011-01-01 00:00:00')
.....
recall: coalesce partition
145

146. long DDL .....
146

147. subpartition templates
147

148. SQL> create table COMP
2 ( tstamp timestamp(6) not null,
3 empno number(10) not null,
4 ename varchar2(10) not null,
5 deptno varchar2(10) not null
6 )
7 PARTITION BY RANGE (TSTAMP)
8 SUBPARTITION BY LIST (deptno)
9 SUBPARTITION TEMPLATE
10 (SUBPARTITION d1 VALUES (1),
11 SUBPARTITION d2 VALUES (2),
12 SUBPARTITION d3 VALUES (3), implicit
13 SUBPARTITION d4 VALUES (4)) subpar's
14 (
15 PARTITION p01 VALUES LESS THAN
16 (TIMESTAMP' 2010-01-01 00:00:00'),
17 PARTITION p02 VALUES LESS THAN
18 (TIMESTAMP' 2010-02-01 00:00:00'),
19 ....
148

149. SQL> select partition_name pname,
2 partition_position pos,
3 high_value
4 from USER_TAB_PARTITIONS
5 where table_name = 'COMP';
PNAME POS HIGH_VALUE
---------- ---------- --------------------------------
P01 1 TIMESTAMP' 2010-01-01 00:00:00'
P02 2 TIMESTAMP' 2010-02-01 00:00:00'
P03 3 TIMESTAMP' 2010-03-01 00:00:00'
P04 4 TIMESTAMP' 2010-04-01 00:00:00'
P05 5 TIMESTAMP' 2010-05-01 00:00:00'
P06 6 TIMESTAMP' 2010-06-01 00:00:00'
P07 7 TIMESTAMP' 2010-07-01 00:00:00'
P08 8 TIMESTAMP' 2010-08-01 00:00:00'
...
149

150. SQL> select subpartition_name pname,
2 subpartition_position pos,
3 high_value
4 from USER_TAB_SUBPARTITIONS
5 where table_name = 'COMP'
6 order by 1,2;
PNAME POS HIGH_VALUE
---------- ---------- ----------------------
P01_D1 1 '1'
P01_D2 2 '2'
P01_D3 3 '3'
P01_D4 4 '4'
P02_D1 1 '1'
P02_D2 2 '2'
P02_D3 3 '3'
P02_D4 4 '4'
P03_D1 1 '1' auto named for
... subpar templates
...
150

151. partitions
logical or physical
151

152. composite (range + list)
since 9
152

153. composite (anything + anything)
since 11
153

154. interval partitioning
11g
154

155. the problem with ranges....
155

156. ... they are a range
156

157. require maintenance
157

158. 25 PARTITION p13 VALUES LESS THAN
26 (TIMESTAMP' 2011-01-01 00:00:00')
27 );
SQL> insert into DEMO
2 values ( to_date('01-JAN-2014'), .... );
insert into DEMO
*
ERROR at line 1:
ORA-14400: inserted partition key does not map to any partition
158

159. insurance policy
159

160. 25 PARTITION p13 VALUES LESS THAN
26 (TIMESTAMP' 2011-01-01 00:00:00')
26 PARTITION pmax VALUES LESS THAN
27 (MAXVALUE)
28 );
magic value
SQL> insert into DEMO
2 values ( to_date('01-JAN-2014'), .... );
1 row created.
160

161. why MAXVALUE might hurt
(part 1)
161

162. split not add
162

163. SQL> alter table DEMO split partition PMAX
2 at ( TIMESTAMP' 2012-02-01 00:00:00')
3 into ( partition p14, partition pmax )
4 /
Table altered.
163

164. hoping for empty partition
164

165. "fast split" partition
165

166. index hassles
see later...
166

167. "solved" in 11g
167

168. 168

169. interval partitioning
169

170. SQL> create table DEMO
2 ( tstamp timestamp(6) not null,
3 empno number(10) not null,
4 ename varchar2(10) not null,
5 deptno varchar2(10) not null
6 )
7 PARTITION BY RANGE (TSTAMP)
8 INTERVAL( NUMTOYMINTERVAL(1,'MONTH'))
9 (
10 PARTITION P00 VALUES LESS THAN
11 (TIMESTAMP' 2010-01-01 00:00:00')
11 );
Table created.
170

171. partitions created as required
171

172. SQL> select PARTITION_NAME, HIGH_VALUE
2 from user_tab_partitions
3 where table_name = 'DEMO';
PARTITION_NAME HIGH_VALUE
------------------------- --------------------------------
P00 TIMESTAMP' 2010-01-01 00:00:00'
SQL> insert into DEMO
2 values ( to_date('12-DEC-2011'),....);
1 row created.
SQL> select PARTITION_NAME, HIGH_VALUE
2 from user_tab_partitions
3 where table_name = 'DEMO';
PARTITION_NAME HIGH_VALUE
------------------------- --------------------------------
P00 TIMESTAMP' 2010-01-01 00:00:00'
SYS_P362 TIMESTAMP' 2012-01-01 00:00:00'
172

173. gaps allowed
173

174. range partition boundaries
Length Length Length
174

175. partition name control lost
can rename....
175

176. convert range to interval
176

177. original range version
SQL> alter table DEMO
2 SET INTERVAL ( NUMTOYMINTERVAL(1,'MONTH') );
Table altered.
177

178. SQL> insert into DEMO
2 values ( to_date('01-JAN-2017'),....);
1 row created.
178

179. SQL> select partition_name pname,
2 partition_position pos,
3 high_value
4 from user_tab_partitions
5 where table_name = 'DEMO';
PNAME POS HIGH_VALUE
------------ ---------- --------------------------------
P01 1 TIMESTAMP' 2010-01-01 00:00:00'
P02 2 TIMESTAMP' 2010-02-01 00:00:00'
P03 3 TIMESTAMP' 2010-03-01 00:00:00'
P04 4 TIMESTAMP' 2010-04-01 00:00:00'
...
P10 10 TIMESTAMP' 2010-10-01 00:00:00'
P11 11 TIMESTAMP' 2010-11-01 00:00:00'
P12 12 TIMESTAMP' 2010-12-01 00:00:00'
P13 13 TIMESTAMP' 2011-01-01 00:00:00'
SYS_P1091 14 TIMESTAMP' 2017-02-01 00:00:00'
179

180. but be careful ...
180

181. hybrid
range range range interval
181

182. is it range or interval ?
182

183. SQL> desc DBA_TAB_PARTITIONS
Name Null? Type
----------------------- -------- ----------------
TABLE_OWNER VARCHAR2(30)
TABLE_NAME VARCHAR2(30)
COMPOSITE VARCHAR2(3)
PARTITION_NAME VARCHAR2(30)
SUBPARTITION_COUNT NUMBER
HIGH_VALUE LONG
? HIGH_VALUE_LENGTH
PARTITION_POSITION
TABLESPACE_NAME
NUMBER
NUMBER
VARCHAR2(30)
...
LOGGING VARCHAR2(7)
COMPRESSION VARCHAR2(8)
COMPRESS_FOR VARCHAR2(18)
NUM_ROWS NUMBER
BUFFER_POOL VARCHAR2(7)
GLOBAL_STATS VARCHAR2(3)
USER_STATS VARCHAR2(3)
183

184. SQL> select o.subname,
2 decode(bitand(tp.flags,32768),
3 32768,'YES','NO') interval
4 from SYS.TABPART$ tp, SYS.OBJ$ o
6 where tp.obj# = o.obj#
6 and o.name = 'DEMO';
SUBNAME INT
------------------------------ ---
P01 NO
P02 NO
P03 NO
P04 NO
P05 NO
...
P11 NO
P12 NO
P13 NO
SYS_P1091 YES
14 rows selected.
184

185. fixed in 11.2
185

186. high range value gets "stuck"
186

187. SQL> insert into DEMO
2 values ( to_date('01-JAN-2017'),...);
1 row created.
SQL> insert into DEMO
2 values ( to_date('01-JAN-2016'),...);
1 row created.
187

188. SQL> select partition_name pname,
2 partition_position pos,
3 high_value
4 from user_tab_partitions
5 where table_name = 'DEMO';
PNAME POS HIGH_VALUE
------------ ---------- -------------------------------
P01 1 TIMESTAMP' 2010-01-01 00:00:00'
P02 2 TIMESTAMP' 2010-02-01 00:00:00'
P03 3 TIMESTAMP' 2010-03-01 00:00:00'
P04 4 TIMESTAMP' 2010-04-01 00:00:00'
...
P13 13 TIMESTAMP' 2011-01-01 00:00:00'
SYS_P1112 14 TIMESTAMP' 2016-02-01 00:00:00'
SYS_P1111 15 TIMESTAMP' 2017-02-01 00:00:00'
188

189. SQL> alter table DEMO drop partition P01;
Table altered.
SQL> alter table DEMO drop partition P02;
Table altered.
SQL> alter table DEMO drop partition P13;
alter table DEMO drop partition P13
*
ERROR at line 1:
ORA-14758: Last partition in the range
section cannot be dropped
189

190. Length Length Length
190

191. workarounds (maybe) unpleasant....
191

192. SQL> alter table DEMO set interval ( );
Table altered.
SQL> alter table DEMO
2 set interval (NUMTOYMINTERVAL(1,'MONTH'));
Table altered.
192

193. SQL> alter table DEMO merge partitions
2 for (TIMESTAMP' 2010-12-30 00:00:00'),
3 for (TIMESTAMP' 2016-01-10 00:00:00');
Table altered.
193

194. 11.2
194

195. SQL> alter table DEMO
2 set interval (NUMTOYMINTERVAL(1,'MONTH'));
Table altered.
195

196. why MAXVALUE might hurt
(part 2)
196

197. SQL> create table DEMO
2 ( tstamp timestamp(6) not null,
3 empno number(10) not null,
4 ename varchar2(10) not null,
5 deptno varchar2(10) not null
6 )
7 PARTITION BY RANGE (TSTAMP)
8 (
9 PARTITION p01 VALUES LESS THAN
10 (TIMESTAMP' 2010-01-01 00:00:00'),
...
25 partition PMAX values less than (MAXVALUE)
26 )
27 /
Table created.
197

198. SQL> alter table DEMO
2 set interval ( NUMTOYMINTERVAL(1,'MONTH') );
*
ERROR at line 1:
ORA-14759: SET INTERVAL is not legal on this table.
198

199. explain plan anomaly
199

200. INTERVAL = "1 million partitions"
200

201. SQL> create table DEMO
2 ( tstamp timestamp(6) not null,
3 empno number(10) not null,
4 ename varchar2(10) not null,
5 deptno varchar2(10) not null
6 )
7 PARTITION BY RANGE (TSTAMP)
8 INTERVAL( NUMTOYMINTERVAL(1,'MONTH'))
9 (
10 PARTITION P00 VALUES LESS THAN
11 (TIMESTAMP' 2010-01-01 00:00:00')
12 );
Table created.
201

202. SQL> select * from DEMO;
------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | | |
| 1 | PARTITION RANGE ALL| | 1 | 1 |1048575|
| 2 | TABLE ACCESS FULL | DEMO | 1 | 1 |1048575|
------------------------------------------------------------
202

203. partitioned tables ...
the bigger picture
203

204. SALES
SQL> desc SALES
Name Null? Type
-------------------- -------- --------------
SALE_DATE NOT NULL DATE
...
2009 2010 2011 2012
SALES_ITEMS
SQL> desc SALES_ITEMS
Name Null? Type
-------------------- -------- -----------
SALE_ID NOT NULL NUMBER(12)
ITEM_ID NOT NULL NUMBER(12)
...
204

205. reference partitions
11g
205

206. SQL> create table PARENT
2 ( d date not null,
3 p number(10) not null,
4 pad char(10)
5 )
6 PARTITION BY RANGE (d)
7 (
8 PARTITION p1 VALUES LESS THAN ( to_date('01-JAN-2010')),
9 PARTITION p2 VALUES LESS THAN ( to_date('01-FEB-2010')),
10 PARTITION p3 VALUES LESS THAN ( to_date('01-MAR-2010')),
11 PARTITION p4 VALUES LESS THAN ( to_date('01-APR-2010')),
12 PARTITION p5 VALUES LESS THAN ( to_date('01-MAY-2010')),
13 PARTITION p6 VALUES LESS THAN ( to_date('01-JUN-2010')),
14 PARTITION p7 VALUES LESS THAN ( to_date('01-JUL-2010')),
15 PARTITION p8 VALUES LESS THAN ( to_date('01-AUG-2010')),
16 PARTITION p9 VALUES LESS THAN ( to_date('01-SEP-2010'))
17 );
Table created.
SQL> alter table PARENT add primary key ( p );
Table altered.
206

207. SQL> create table CHILD
2 ( p number(10) not null,
3 c number(10) not null,
4 constraint CHILD_FK foreign key ( p )
5 references PARENT (p)
6 on delete cascade
7 )
8 PARTITION BY REFERENCE (CHILD_FK)
9 /
Table created.
207

208. SQL> insert into PARENT
2 select sysdate+rownum, rownum, rownum
3 from dual connect by level <= 100
4 /
100 rows created.
SQL> insert into CHILD
2 select rownum, rownum
3 from dual connect by level <= 100
4 /
100 rows created.
208

209. SQL> exec dbms_stats.gather_table_stats(user,'CHILD');
PL/SQL procedure successfully completed.
SQL> select partition_name, num_rows
2 from USER_TAB_PARTITIONS
3 where table_name = 'CHILD';
PARTITION_NAME NUM_ROWS
------------------------------ ----------
P1 0
P2 0
P3 0
P4 0
P5 9
P6 31
P7 30
P8 30
P9 0
209

210. seems good .... but
210

211. null
SQL> create table CHILD
2 ( p number(10),
3 c number(10),
4 constraint CHILD_FK foreign key ( p )
5 references PARENT (p)
6 )
7 PARTITION BY REFERENCE (CHILD_FK)
8 /
PARTITION BY REFERENCE (CHILD_FK)
*
ERROR at line 7:
ORA-14652: reference partitioning foreign key is not supported
211

212. SQL> create table PARENT
2 ( d date not null,
3 p number(10) not null,
4 pad char(10)
5 )
6 PARTITION BY RANGE (d)
7 INTERVAL( NUMTOYMINTERVAL(1,'MONTH'))
8 ( PARTITION VALUES LESS THAN ( to_date('01-JAN-2010')) );
Table created.
SQL> create table CHILD
2 ( p number(10) not null,
3 c number(10) not null,
4 constraint CHILD_FK foreign key ( p )
5 references PARENT (p)
6 on delete cascade
7 )
8 PARTITION BY REFERENCE (CHILD_FK);
create table CHILD
*
ERROR at line 1:
ORA-14659: Partitioning method of the parent table is not supported
212

213. but the following "works"....
213

214. SQL> alter table PARENT
2 set INTERVAL( NUMTOYMINTERVAL(1,'MONTH'));
Table altered.
SQL> insert into PARENT values (sysdate+1000,-1,'x');
1 row created.
SQL> select partition_name
2 from user_tab_partitions
pk=-1
3 where table_name = 'PARENT';
PARTITION_NAME
------------------------------
SYS_P1196
P1
P2
P3
...
214

215. SQL> insert into CHILD values (-1,0);
insert into CHILD values (-1,0)
*
ERROR at line 1:
ORA-14401: inserted partition key is outside
specified partition
215

216. dropping requires order
216

217. SQL> drop table PARENT;
drop table PARENT
*
ERROR at line 1:
ORA-02449: unique/primary keys in table referenced by
foreign keys
SQL> drop table PARENT cascade constraints;
drop table PARENT cascade constraints
*
ERROR at line 1:
ORA-14656: cannot drop the parent of a reference-
partitioned table
217

218. Suboptimal Query when Gather Partition Stats on Reference Partitioned
Wrong Results In 11g On Reference Partitioned Table
ORA-7445[KKPAMDINFO] ON SELECT AGAINST A REFERENCE
PARTITIONED TABLE
its a very new feature
Drop of reference partition not allowed (ORA-2266) with FK between siblings
UNIQUE INDEX NOT WORKING PROPERLY ON PARTITIONED BY
REFERENCE TABLE
ALLOW DROP PARTITION TO SUCCEED ON REFERENCED PARTITION
WITHOUT CORRUPTING DATA.
218

219. Part 2
indexes on partitioned tables
219

220. 220

221. SALES
2009 2010 2011 2012
SQL> create index SALES_IX on SALES ( CUSTOMER );
221

222. 2009 2010 2011 2012
222

223. "global" index
223

224. big....really big
extended rowid
224

225. ILM issues
225

226. 2009 2010 2011 2012
SQL> alter table SALES drop partition SALES_2009
226

227. SQL> create index DEMO_IX on DEMO ( empno );
Index created.
SQL> select status
2 from user_indexes
3 where index_name = 'DEMO_IX';
STATUS
--------
VALID
SQL> select * from DEMO where empno = 123;
---------------------------------------------------------------------
| Id | Operation | Name |Pstart| Pstop |
--------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | |
| 1 | TABLE ACCESS BY GLOBAL INDEX ROWID| DEMO |ROWID | ROWID |
|* 2 | INDEX RANGE SCAN | DEMO_IX | | |
---------------------------------------------------------------------
227

228. SQL> alter table DEMO drop partition P06;
Table altered.
SQL> select status
2 from user_indexes
3 where index_name = 'DEMO_IX';
STATUS
--------
UNUSABLE
SQL> select * from DEMO where empno = 123;
------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
------------------------------------------------------------
| 0 | SELECT STATEMENT | | 50 | | |
| 1 | PARTITION RANGE ALL| | 50 | 1 | 13 |
|* 2 | TABLE ACCESS FULL | DEMO | 50 | 1 | 13 |
------------------------------------------------------------
228

229. SQL> select value
2 from v$parameter
3 where name = 'skip_unusable_indexes';
VALUE
------------------------------
TRUE
229

230. keep the index valid
230

231. 2009 2010 2011 2012
SQL> alter table SALES drop partition SALES_2009
2 update indexes;
231

232. undo
large delete
redo
232

233. merge
split
similar issues
exchange
233

234. an alternative
234

235. "local" index
235

236. 2009 2010 2011 2012
SQL> create index SALES_IX ON SALES ( CUSTOMER )
2 LOCAL;
236

237. smaller chunks
237

238. smaller rowid's
238

239. 2009 2010 2011 2012
SQL> alter table SALES drop partition SALES_2009;
239

240. SQL> create index DEMO_IX on DEMO ( empno ) LOCAL;
Index created.
SQL> select partition_name, status
2 from user_ind_partitions
3 where index_name = 'DEMO_IX';
PARTITION_NAME STATUS
------------------------------ -------
P01 USABLE
P02 USABLE
P03 USABLE
P04 USABLE
P05 USABLE
P06 USABLE
P07 USABLE
...
240

241. SQL> alter table DEMO drop partition P06;
Table altered.
SQL> select partition_name, status
2 from user_ind_partitions
3 where index_name = 'DEMO_IX';
PARTITION_NAME STATUS
------------------------------ -------
P01 USABLE
P02 USABLE
P03 USABLE
P04 USABLE
P05 USABLE
P06 USABLE
P07 USABLE
...
241

242. awesome for ILM
242

243. handlng old data
243

244. 2009 2010 2011 2012
SQL> alter table SALES move partition SALES_2009
2 COMPRESS;
244

245. RMAN
2009 2010 2011 2012
SQL> alter table SALES move partition SALES_2009
2 TABLESPACE CRAPPY_OLD_DISK;
SQL> alter tablespace CRAPPY_OLD_DISK READ ONLY;
245

246. 11.2 very cool
246

247. "segment-less" segments
247

248. 2009 2010 2011 2012
SQL> alter index SALES_IX partition SALES_IX_2009
2 UNUSABLE;
248

249. handlng new data
249

250. 2010 2011 2013
2012
2013
SQL> alter table SALES exchange
2 partition SALES_2013 with
3 table NEW_SALES;
250

251. local = good

252. global = bad
252

253. NO !
253

254. different "target audience"
254

255. SQL> create index SALES_IX on SALES ( CUSTOMER ) LOCAL;
123 123 123 123
2009 2010 2011 2012
SQL> select *
2 from SALES
3 where CUSTOMER = 123;
255

256. can be much much worse...
256

257. WA VIC WA VIC WA VIC WA VIC
2009 2010 2011 2012
NSW QLD NSW QLD NSW QLD NSW QLD
SQL> select *
2 from SALES
3 where CUSTOMER = 123;
257

258. explain plan
258

259. SQL> select * from SALES
2 where CUSTOMER= 123;
----------------------------------------------------------------------
| Id | Operation | Name |Pstart | Pstop |
----------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | |
| 1 | PARTITION RANGE ALL | | 1 | 13 |
| 2 | TABLE ACCESS BY LOCAL INDEX ROWID| SALES | 1 | 13 |
|* 3 | INDEX RANGE SCAN | SALES_IX| 1 | 13 |
----------------------------------------------------------------------
259

260. SQL> create index SALES_IX on SALES ( CUSTOMER ) LOCAL;
123
123
123
123
2009 2010 2011 2012
SQL> select *
2 from SALES
3 where CUSTOMER = 123;
260

261. "so global for
index lookups then"....
261

262. NO !
262

263. 123
2009 2010 2011 2012
SQL> select *
2 from SALES
3 where CUSTOMER = 123
4 and YEAR = 2010;
263

264. careful design
264

265. application compromises
eg unique keys
265

266. so far ... "equipartition"
266

267. SALES
SQL> create index SALES_IX ON SALES ( CUSTOMER )
2 global
3 partition by ....
267

268. 2009 2010 2011 2012
SQL> create index SALES_IX
2 on SALES ( location, empno )
3 global partition by range ( location )
4 ( partition p0 values less than (1),
6 partition p1 values less than (2),
...
12 partition pmax values less than (maxvalue)
13 );
Index created. 268

269. rare ....
269

270. ...one special case
10g+
270

271. hash partitioned index
271

272. recall: hash partitioned tables
272

273. ASSM
concurrency
273

274. indexes a problem
274

275. 275

276. hash partitioned indexes
276

277. SQL> create index SALES_PK on SALES( TXN_ID )
2 global partition by hash ( TXN_ID )
3 partitions 8
4 /
Index created.
277

278. 278

279. only for equality
primary keys
279

280. beware the NOSORT
280

281. reference partitions and indexes
281

282. SALES
2009 2010 2011 2012
SALES_ITEMS
2009 2010 2011 2012
282

283. take care with ILM
283

284. SQL> alter table PARENT drop partition P6;
Table altered.
SQL> select partition_name
2 from user_tab_partitions
3 where table_name = 'CHILD';
PARTITION_NAME
------------------------------
P1
P2
P3
P4
P5
P7
P8
P9
284

285. SQL> alter table PARENT truncate partition P7;
alter table PARENT truncate partition P7
*
ERROR at line 1:
ORA-02266: unique/primary keys in table referenced by
enabled foreign keys
SQL> alter table CHILD truncate partition P7;
Table truncated.
SQL> alter table PARENT truncate partition P7;
Table truncated.
gap
285

286. SQL> select index_name, status from user_indexes;
INDEX_NAME STATUS
------------------------------ --------
PARENT_PK UNUSABLE
CHILD_PK UNUSABLE
286

287. exchange is difficult...
287

288. plus more restrictions.....
288

289. Part 3
partition queries
289

290. partition pruning
290

291. efficiency =
data required /
data scanned
291

292. SQL> create table DEMO
2 ( tstamp timestamp(6) not null,
3 empno number(10) not null,
4 ename varchar2(10) not null,
5 deptno varchar2(10) not null
6 )
7 PARTITION BY RANGE (TSTAMP)
8 (
9 PARTITION p01 VALUES LESS THAN
10 (TIMESTAMP' 2010-01-01 00:00:00'),
11 PARTITION p02 VALUES LESS THAN
12 (TIMESTAMP' 2010-02-01 00:00:00'),
13 PARTITION p03 VALUES LESS THAN
14 (TIMESTAMP' 2010-03-01 00:00:00'),
...
...
25 PARTITION p13 VALUES LESS THAN
26 (TIMESTAMP' 2011-01-01 00:00:00')
27 );
Table created.
292

293. 360 days
SQL> insert /*+ APPEND */ into DEMO
2 select trunc(sysdate,'YYYY')+rownum/( 1000000 / 360 ),
3 rownum,
4 rownum,
5 mod(rownum,1000)
6 from dual
7 connect by level <= 1000000
8 /
1000000 rows created.
293

294. SQL> select * from DEMO
2 where TSTAMP = to_date('01-JUN-2010');
---------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
---------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | | |
| 1 | PARTITION RANGE SINGLE| | 1 | 7 | 7 |
|* 2 | TABLE ACCESS FULL | DEMO | 1 | 7 | 7 |
---------------------------------------------------------------
294

295. SQL> select * from DEMO
2 where TRUNC(TSTAMP) = to_date('01-JUN-2010');
------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
------------------------------------------------------------
| 0 | SELECT STATEMENT | | 10000 | | |
| 1 | PARTITION RANGE ALL| | 10000 | 1 | 13 |
|* 2 | TABLE ACCESS FULL | DEMO | 10000 | 1 | 13 |
------------------------------------------------------------
295

296. static versus dynamic
296

297. SQL> select * from DEMO
2 where TSTAMP = :b1;
---------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
---------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | | |
| 1 | PARTITION RANGE SINGLE| | 1 | KEY | KEY |
|* 2 | TABLE ACCESS FULL | DEMO | 1 | KEY | KEY |
---------------------------------------------------------------
297

298. lots of power
varies by version
298

299. SQL> select * from DEMO
2 where TSTAMP between to_date('12-JAN-2010')
3 and to_date('07-FEB-2010')
4 or TSTAMP between to_date('03-JUN-2010')
5 and to_date('06-AUG-2010');
-----------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
-----------------------------------------------------------
| 0 | SELECT STATEMENT | | 240K| | |
| 1 | PARTITION RANGE OR| | 240K|KEY(OR)|KEY(OR)|
|* 2 | TABLE ACCESS FULL| DEMO | 240K|KEY(OR)|KEY(OR)|
-----------------------------------------------------------
299

300. SQL> select * from DEMO
2 where TSTAMP in (to_date('01-JUN-2010'),
3 to_date('01-DEC-2010'));
---------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
---------------------------------------------------------------
| 0 | SELECT STATEMENT | | 2 | | |
| 1 | PARTITION RANGE INLIST| | 2 |KEY(I) |KEY(I) |
|* 2 | TABLE ACCESS FULL | DEMO | 2 |KEY(I) |KEY(I) |
---------------------------------------------------------------
300

301. limitations of explain plan
301

302. SQL> select * from DEMO
2 where TSTAMP in (to_date('01-JUN-2010'),
3 to_date('01-DEC-2010'));
---------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
---------------------------------------------------------------
| 0 | SELECT STATEMENT | | 2 | | |
| 1 | PARTITION RANGE INLIST| | 2 |KEY(I) |KEY(I) |
|* 2 | TABLE ACCESS FULL | DEMO | 2 |KEY(I) |KEY(I) |
---------------------------------------------------------------
JUN JUL AUG SEP OCT NOV DEC
302

303. July
SQL> alter table DEMO move partition P08 tablespace USERS;
Table altered.
SQL> alter tablespace USERS offline;
Tablespace altered.
SQL> select count(*) from DEMO
2 where TSTAMP in (to_date('01-JUN-2010'),
3 to_date('01-DEC-2010'));
COUNT(*)
----------
1234
303

304. SQL> select count(*) from DEMO
2 where TSTAMP in (to_date('01-JUN-2010'),
3 to_date('01-JUL-2010'));
select count(*) from DEMO
*
ERROR at line 1:
ORA-00376: file 4 cannot be read at this time
ORA-01110: data file 4: 'C:ORACLEDB11USERS01.DBF'
304

305. "NO OP" pruning
305

306. SQL> select * from DEMO
2 where TSTAMP = to_date('01-JUN-2020');
--------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
--------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | | |
| 1 | PARTITION RANGE EMPTY| | 1 |INVALID|INVALID|
|* 2 | TABLE ACCESS FULL | DEMO | 1 |INVALID|INVALID|
--------------------------------------------------------------
306

307. pruning lists
307

308. SQL> create table SALES
2 ( sales_id varchar2(10) not null,
3 location varchar2(3) not null,
4 amount number(10)
5 )
6 PARTITION BY LIST (location)
7 (
8 PARTITION NSW VALUES ('NSW'),
9 PARTITION WA VALUES ('WA'),
10 PARTITION QLD VALUES ('QLD'),
11 PARTITION SA VALUES ('SA'),
12 PARTITION VIC VALUES ('VIC'),
13 PARTITION TERR VALUES ('ACT','NT')
14 )
15 /
Table created.
308

309. SQL> select * from sales
2 where location = 'WA';
---------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
---------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | | |
| 1 | PARTITION LIST SINGLE| | 1 | KEY | KEY |
| 2 | TABLE ACCESS FULL | SALES | 1 | 2 | 2 |
---------------------------------------------------------------
309

310. SQL> select * from sales
2 where location like 'S%';
---------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
---------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | | |
| 1 | PARTITION LIST SINGLE| | 1 | KEY | KEY |
| 2 | TABLE ACCESS FULL | SALES | 1 | 4 | 4 |
---------------------------------------------------------------
310

311. SQL> select * from sales
2 where location NOT in ('WA','NSW');
------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | | |
| 1 | PARTITION LIST ALL| | 1 | 1 | 6 |
|* 2 | TABLE ACCESS FULL| SALES | 1 | 1 | 6 |
------------------------------------------------------------
311

312. pruning composites
312

313. SQL> create table COMP
2 ( tstamp timestamp(6) not null,
3 empno number(10) not null,
4 ename varchar2(10) not null,
5 deptno varchar2(10) not null
6 )
7 PARTITION BY RANGE (TSTAMP)
8 SUBPARTITION BY LIST (deptno)
9 SUBPARTITION TEMPLATE
10 (SUBPARTITION d1 VALUES (1),
11 SUBPARTITION d2 VALUES (2),
12 SUBPARTITION d3 VALUES (3),
13 SUBPARTITION d4 VALUES (4))
14 (
15 PARTITION p01 VALUES LESS THAN
16 (TIMESTAMP' 2010-01-01 00:00:00'),
17 PARTITION p02 VALUES LESS THAN
18 (TIMESTAMP' 2010-02-01 00:00:00'),
19 ....
313

314. SQL> select * from COMP
2 where TSTAMP = to_date('01-JUN-2010')
3 and DEPTNO = 2;
---------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
---------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | | |
| 1 | PARTITION RANGE SINGLE| | 1 | 7 | 7 |
| 2 | PARTITION LIST SINGLE| | 1 | 2 | 2 |
|* 3 | TABLE ACCESS FULL | COMP | 1 | 26 | 26 |
---------------------------------------------------------------
314

315. SQL> select * from COMP
2 where DEPTNO = 3;
---------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
---------------------------------------------------------------
| 0 | SELECT STATEMENT | | 250K| | |
| 1 | PARTITION RANGE ALL | | 250K| 1 | 13 |
| 2 | PARTITION LIST SINGLE| | 250K| 3 | 3 |
| 3 | TABLE ACCESS FULL | COMP | 250K| KEY | KEY |
---------------------------------------------------------------
315

316. pruning by subquery
316

317. SQL> select e.deptno, max(d.empno)
2 from DEMO d, scott.emp e
3 where d.tstamp = e.hiredate
4 and e.sal < 10000
5 group by e.deptno;
-------------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
-------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 14 | | |
| 1 | HASH GROUP BY | | 14 | | |
|* 2 | HASH JOIN | | 14 | | |
|* 3 | TABLE ACCESS FULL | EMP | 14 | | |
| 4 | PARTITION RANGE SUBQUERY| | 1000K|KEY(SQ)|KEY(SQ)|
| 5 | TABLE ACCESS FULL | DEMO | 1000K|KEY(SQ)|KEY(SQ)|
-------------------------------------------------------------------
317

318. 11g
maybe 10.2 ?
318

319. SQL> select e.deptno, max(d.empno)
2 from demo d, scott.emp e
3 where d.tstamp = e.hiredate
4 and e.sal < 10000
5 group by e.deptno;
-----------------------------------------------------------------
| Id | Operation | Name | Pstart| Pstop |
-----------------------------------------------------------------
| 0 | SELECT STATEMENT | | | |
| 1 | HASH GROUP BY | | | |
|* 2 | HASH JOIN | | | |
| 3 | PART JOIN FILTER CREATE | :BF0000 | | |
|* 4 | TABLE ACCESS FULL | EMP | | |
| 5 | PARTITION RANGE JOIN-FILTER| |:BF0000|:BF0000|
| 6 | TABLE ACCESS FULL | DEMO |:BF0000|:BF0000|
-----------------------------------------------------------------
319

320. | 3 | PART JOIN FILTER CREATE | :BF0000 | | |
|* 4 | TABLE ACCESS FULL | EMP | | |
| 5 | PARTITION RANGE JOIN-FILTER| |:BF0000|:BF0000|
| 6 | TABLE ACCESS FULL | DEMO |:BF0000|:BF0000|
-----------------------------------------------------------------
huh ?
320

321. bloom filters
321

322. The Bloom filter...is a space-efficient
probabilistic data structure that is
used to test whether an element is
a member of a set.
- Wikipedia
322

323. wtf ?
323

324. "b" bits
"h" hash functions
324

325. b0
b1
h1 b2
b3
data h2
b4
h3
b5
b6
b7
325

326. b0
b1
h1 b2
b3
data h2
b4
h3
b5
b6
b7
326

327. b0
b1
h1 b2
b3
data h2
b4
h3
b5
b6
b7
327

328. b0
b1
h1 b2
b3
data h2
b4
h3
b5
b6
b7
328

329. b0
b1
h1 b2
b3
data h2
b4
h3
b5
b6
b7
329

330. b0
b1
b2 h1
b3
h2 matching
b4 data?
h3
b5
b6
b7
330

331. b0
b1
b2 h1
do the b3
"real" h2 matching
work
b4 data?
h3
b5
b6
b7
331

332. b0
b1
b2 h1
do the b3
"real" h2 matching
work
b4 data?
h3
b5
b6
b7
332

333. "meta-poor"
333

334. 334

335. 335

336. "are you joking...try in 6 months"
336

337. "yes, we have some"
337

338. 338

339. false positives possible
339

340. false negatives impossible
340

341. they are here to stay....
341

342. SQL> alter session set "_bloom_filter_enabled" = false;
SQL> alter session set "_bloom_pruning_enabled" = false;
342

343. other partitioning benefits
343

344. partition wise join
344

345. SQL> select d.*, d2.*
2 from DEMO d, DEMO2 d2
3 where d.TSTAMP = d2.TSTAMP;
-------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
-------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1003K| | |
| 1 | PARTITION RANGE ALL| | 1003K| 1 | 13 |
|* 2 | HASH JOIN | | 1003K| | |
| 3 | TABLE ACCESS FULL| DEMO | 1000K| 1 | 13 |
| 4 | TABLE ACCESS FULL| DEMO2 | 1000K| 1 | 13 |
-------------------------------------------------------------
345

346. "big deal"
346

347. meta-poor
347

348. 348

349. 1000 cars north of Perth
1000 cars south of Perth
349

350. 350

351. "replace damaged models
at the north yard with matching
models from the south yard"
351

352. 352

353. SQL> select ...
2 from NORTH n, SOUTH s
3 where n.MODEL = s.MODEL
----------------------------------------------------------------
| Id | Operation | Name | Pstart| Pstop |
----------------------------------------------------------------
| 0 | SELECT STATEMENT | | | |
|* 1 | HASH JOIN | | | |
| 3 | PARTITION RANGE ALL | | 1 | 2 |
| 4 | TABLE ACCESS FULL | NORTH | 1 | 2 |
| 5 | PARTITION RANGE ALL | | 1 | 2 |
| 6 | TABLE ACCESS FULL | SOUTH | 1 | 2 |
----------------------------------------------------------------
353

354. NORTH
4WD SMART CARS
SOUTH
4WD SMART CARS
354

355. partition wise join
355

356. SQL> select ...
2 from NORTH n, SOUTH s
3 where n.model = s.model
-------------------------------------------------------------
| Id | Operation | Name | Rows | Pstart| Pstop |
-------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1003K| | |
| 1 | PARTITION RANGE ALL| | 1003K| 1 | 2 |
|* 2 | HASH JOIN | | 1003K| | |
| 3 | TABLE ACCESS FULL| NORTH | 1000K| 1 | 2 |
| 4 | TABLE ACCESS FULL| SOUTH | 1000K| 1 | 2 |
-------------------------------------------------------------
356

357. great parallel benefits
357

358. SQL> select /*+ PARALLEL(n) PARALLEL(s) */ ...
2 from north n, south s
3 where n.model = s.model
----------------------------------------------------------------------------------------------
| Id | Operation | Name | Pstart| Pstop | TQ |IN-OUT| PQ Distrib |
----------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | | | |
| 1 | PX COORDINATOR | | | | | | |
| 2 | PX SEND QC (RANDOM) | :TQ10001 | | | Q1,01 | P->S | QC (RAND) |
|* 3 | HASH JOIN | | | | Q1,01 | PCWP | |
| 4 | PX BLOCK ITERATOR | | 1 | 2 | Q1,01 | PCWC | |
| 5 | TABLE ACCESS FULL | NORTH | 1 | 2 | Q1,01 | PCWP | |
| 6 | BUFFER SORT | | | | Q1,01 | PCWC | |
| 7 | PX RECEIVE | | | | Q1,01 | PCWP | |
| 8 | PX SEND BROADCAST LOCAL| :TQ10000 | | | Q1,00 | P->P | BCST LOCAL |
| 9 | PX BLOCK ITERATOR | | 1 | 2 | Q1,00 | PCWC | |
| 10 | TABLE ACCESS FULL | SOUTH | 1 | 2 | Q1,00 | PCWP | |
----------------------------------------------------------------------------------------------
358

359. Slave 1 Slave 2
NORTH
4WD SMART CARS
SOUTH
4WD SMART CARS
Slave 3 Slave 4
359

360. partitions must match exactly
360

361. if not, better in 11g
361

362. fallback to bloom filter
362

363. SQL> select ...
2 from NORTH n, SOUTH s
3 where n.model = s.model
----------------------------------------------------------------
| Id | Operation | Name | Pstart| Pstop |
----------------------------------------------------------------
| 0 | SELECT STATEMENT | | | |
|* 1 | HASH JOIN | | | |
| 2 | PART JOIN FILTER CREATE | :BF0000 | | |
| 3 | PARTITION RANGE ALL | | 1 | 2 |
| 4 | TABLE ACCESS FULL | NORTH | 1 | 2 |
| 5 | PARTITION RANGE JOIN-FILTER| |:BF0000|:BF0000|
| 6 | TABLE ACCESS FULL | SOUTH |:BF0000|:BF0000|
----------------------------------------------------------------
363

364. if nececssary, brew your own
don't assume
364

365. 365

366. wrap up
366

367. all positive
367

368. know the pitfalls
368

369. pitfalls # 1
369

370. SQL> select * from v$option;
PARAMETER VALUE
-------------------------------------------------- --------
Partitioning TRUE
Objects TRUE
Real Application Clusters TRUE
Advanced replication TRUE
Bit-mapped indexes TRUE
Connection multiplexing TRUE
Connection pooling TRUE
Database queuing TRUE
Incremental backup and recovery TRUE
Instead-of triggers TRUE
Parallel backup and recovery TRUE
Parallel execution TRUE
Parallel load TRUE
370

372. even in EE
372

373. worth the cost....
373

374. pitfalls # 2
374

375. boundary cases
constraint validation
375

376. boundary cases
statistics gathering
376

377. boundary cases
shared pool
377

378. boundary cases
reference partitions
378

379. test with sql trace
379

380. Connor McDonald
OracleDBA
co.uk
380

381. ORA-00041
“active time limit exceeded - session terminated”
www.oracledba.co.uk 381