Title: Enabling Enterprise Provisioning and Security in Oracle Portal
1Aces in the Hole Learning Advanced SQL
Techniques from the OTN Forum Pros
Greg PikePiocon Technologies
2Greg PikeManaging PrincipalPiocon Technologies
- History 15 year Oracle solution provider
- Home ChicagoLand
- Focus Business Intelligence, Data Warehousing,
Portal, web applications, devious SQL - Blog www.SingleQuery.com
- Client list includes
3The Oracle Discussion Forums
- An interactive community for sharing information,
questions, and comments about Oracle products and
related technologies - Most forums are moderated by product managers,
and all of them are frequently visited by
knowledgeable users from the community - Anyone can read messages but must be a registered
member to post a question or response - Posts to the SQL and PL/SQL Forum are often
answered in minutes
Source http//www.oracle.com/technology/forums/f
aq.html
4Who Can Learn from the OTN SQL and PL/SQL Forum?
- Beginners Got a questionits probably already
been answered 100 times. Please search for a
solution first, but dont be shy to ask - Intermediate Learners The SQL and PL/SQL Forum
has a wealth of knowledge on every imaginable
topic - Experts You may not feel like an expert after a
visit to this Forum - Unique Problem This is your real-time resource
for solutions - Contributor Get involved and share your
expertise
5Who Contributes? Introducing the Experts and
Recent Forum Post Counts
- Warren Tolentino 4,400
- Devmiral 2,200
- Nicolas Gasparotto 14,900
- Marias 1,300
- The Flying Spontinalli 700
- Rob van Wijk 3,900
- Michaels 3,400
- John Spencer 3,700
- Justin Cave 18,700
- Billy Verreynne 5,500
- APC 9,500
- BluShadow 6,200
- William Robertson 4,500
- Volder 950
- Yingkuan 7000
- Kamal Kishore 7,300
and 100s of people worldwide with a passion for
problem solving
6QIf the advice is free, how good can it be?A
The Program. Enough said.
- The Oracle ACE program formally recognizes
advocates of Oracle technology with strong
credentials as evangelists and educators - Oracle ACE recipients are chosen based on their
significant contributions and activity in the
Oracle technical community with candidates
nominated by anyone in the Oracle Technology and
Applications communities.
Source http//www.oracle.com/technology/community
/oracle_ace/index.html
7The Oracle Aces
- Oracle ACEs are known for their strong
credentials as Oracle community enthusiasts and
advocates with candidates nominated by anyone in
the Oracle Technology and Applications
communities. - Technical proficiency
- Oracle-related blog
- Oracle discussion forum activity
- Published white paper(s) and/or article(s)
- Presentation experience
- Beta program participant
- Oracle user group member
- Oracle certification
8Just a Few of the 188 Oracle Aces
- Cary Milsap (speaking today)
- Peter Koletzke (speaking today)
- Dan Norris (Piocon)
- Paul Dorsey
- Steven Feuerstein
- Ken Jacobs
- Tom Kyte
- Mark Rittman
- Laurent Schneider
9Case Study Examining a Recent Post
- The following post is from May 28, 2007 and
elicited 33 replies from long-time Forum
contributors including Oracle Aces - http//forums.oracle.com/forums/thread.jspa?messag
eID1864354 - Only a portion of the solutions are presented
here and the supporting commentary is omitted.
Some queries have been altered to fit on the page
but retain their basic logic - Thanks to the following OTN experts who
contributed to this thread (OTN handle shown)
- Warren Tolentino
- Devang Bhatt (devmiral)
- Nicolas Gasparotto
- marias
- The Flying Spontinalli
- Rob van Wijk
- michaels
10The Original Question
I need to get the count on how many customers
answered for each set of questions. For the
above data, this should be the output
Questions IDs Customer Count 1
1 1,2,4 2 3,4
2 2,3 1 2
1 The Question IDs can have as
many as 10 questions. Thanks in advance.
- I need your help to generate a report. I'm using
Oracle 9i database. This is our data - Customer_ID Question_ID 10001
1 10002 1
10002 2 10002
4 10003 3 10003
4 10004
2 10004 3 10005
1 10005 2
10005 4 10006
3 10006 4 10007
2
11Examining a Few of the Posted Solutions
- Method 1 Hierarchical Query
- Method 2 COLLECT
- Method 3 XML
- Method 4 MODEL
- Method 5 Pipelined Funtions
12Method 1 Hierarchical Query (Warren)
- For querying datasets that contain a parent-child
relationship between rows - Recursively walks through the tree of
relationships from the top-down or bottom-up - Includes tools for determining location in the
hierarchy and the nature of individual nodes
13Method 1 Hierarchical Query
- SELECT ci2.questions,
- COUNT(ci2.cnt) Customer Count"
- FROM (SELECT ci1.customer_id,
- SUBSTR(MAX(SUBSTR(SYS_CONNECT_
BY_PATH - (ci1.question_id,','),2)),1,40
) questions, - ci1.cnt
- FROM (
SELECT customer_id,
question_id,
ROW_NUMBER() OVER (PARTITION BY
customer_id ORDER BY
customer_id,
question_id) rn,
COUNT() OVER (PARTITION BY
customer_id,question_id) cnt
FROM customer_inquiry
) ci1 DTSRT
WITH ci1.rn 1 CONNECT BY ci1.rn
PRIOR ci1.rn 1 AND PRIOR
ci1.customer_id ci1.customer_id
GROUP BY ci1.customer_id, ci1.cnt )
ci2 GROUP BY questions
14Step 1 The pseudo-parent-child relationship
- SELECT customer_id,
- question_id,
- ROW_NUMBER() OVER (PARTITION BY
- customer_id ORDER BY
- customer_id, question_id) rn,
- COUNT() OVER (PARTITION BY
- customer_id,question_id) cnt
- FROM customer_inquiry
Customer_ID Question_ID 10001 1
10002 1 10002 2
10002 4 10003 3 10003
4 10004 2 10004 3
10005 1 10005 2
10005 4 10006 3 10006
4 10007 2
Customer_ID Question_ID RN CNT 10001
1 1 1 10002 1 1 1
10002 2 2 1 10002 4
3 1 10003 3 1 1
10003 4 2 1 10004 2
1 1 10004 3 2 1
10005 1 1 1 10005 2
2 1 10005 4 3 1
10006 3 1 1 10006 4
2 1 10007 2 1 1
15Step 2 Employ SYS_CONNECT_BY_PATH
- SELECT ci2.questions,
- COUNT(ci2.cnt) Customer Count"
- FROM (SELECT ci1.customer_id,
- SUBSTR(MAX(SUBSTR(SYS_CONNECT_
BY_PATH - (ci1.question_id,','),2)),1,40
) questions, - ci1.cnt
- FROM (
SELECT customer_id,
question_id,
ROW_NUMBER() OVER (PARTITION BY
customer_id ORDER BY
customer_id,
question_id) rn,
COUNT() OVER (PARTITION BY
customer_id,question_id) cnt
FROM customer_inquiry
) ci1 START
WITH ci1.rn 1 CONNECT BY ci1.rn
PRIOR ci1.rn 1 AND PRIOR
ci1.customer_id ci1.customer_id
GROUP BY ci1.customer_id, ci1.cnt )
ci2 GROUP BY questions
SYS_CONNECT_BY_PATH returns the path of a column
value from root to node, with column values
separated by char for each row returned by
CONNECT BY condition.
16Step 2 Employ SYS_CONNECT_BY_PATH
- SELECT ci2.questions,
- COUNT(ci2.cnt) Customer Count"
- FROM (SELECT ci1.customer_id,
- SUBSTR(MAX(SUBSTR(SYS_CONNECT_
BY_PATH - (ci1.question_id,','),2)),1,40
) questions, - ci1.cnt
- FROM (
Questions IDs Customer Count 1
1 1,2,4 2 3,4
2 2,3 1 2
1
SYS_CONNECT_BY_PATH returns the path of a column
value from root to node, with column values
separated by char for each row returned by
CONNECT BY condition.
17Method 2 COLLECT (Greg Pike)
- COLLECT takes as its argument a column of any
type and creates a nested table of the input type
out of the rows selected - GROUP BY can determine how the rows are COLLECTED
- The database creates its own collection object to
hold the data - For the required output, CAST the results into a
more usable form - Get the data out of the collection with a
function
18Method 2 The Query
- SELECT SUBSTR(col,1,10) questions,
- COUNT()
- FROM (
- SELECT customer_id,
- tab_to_string(
- CAST(
-
- AS t_number_tab
- )
- ) col
- FROM answers
- GROUP BY customer_id
- )
- GROUP BY col
COLLECT(question_id)
19Step 1 COLLECT
- SELECT customer_id cust_id,
- COLLECT(question_id)
- FROM customer_inquiry
- GROUP BY customer_id
Customer_ID Question_ID 10001 1
10002 1 10002 2
10002 4 10003 3 10003
4 10004 2 10004 3
10005 1 10005 2
10005 4 10006 3 10006
4 10007 2
CUST_ID COLLECT(QUESTION_ID) -------
--------------------------------- 10001
SYSTP3f5GcsxkSvyjQSG5pDbjhA(1) 10002
SYSTP3f5GcsxkSvyjQSG5pDbjhA(1, 2, 4) 10003
SYSTP3f5GcsxkSvyjQSG5pDbjhA(3, 4) 10004
SYSTP3f5GcsxkSvyjQSG5pDbjhA(2, 3) 10005
SYSTP3f5GcsxkSvyjQSG5pDbjhA(1, 2, 4) 10006
SYSTP3f5GcsxkSvyjQSG5pDbjhA(3, 4) 10007
SYSTP3f5GcsxkSvyjQSG5pDbjhA(2)
COLLECT takes as its argument a column of any
type and creates a nested table of the input type
out of the rows selected.
20Step 2 CAST(COLLECT)
- CREATE OR REPLACE TYPE t_number_tab AS TABLE OF
NUMBER - SELECT customer_id,
- CAST(COLLECT(question_id) AS
t_number_tab) col - FROM customer_inquiry
- GROUP BY customer_id
Customer_ID Question_ID 10001 1
10002 1 10002 2
10002 4 10003 3 10003
4 10004 2 10004 3
10005 1 10005 2
10005 4 10006 3 10006
4 10007 2
CUST_ID COLLECT(QUESTION_ID) -------
--------------------- 10001 T_NUMBER_TAB(1)
10002 T_NUMBER_TAB(1, 2, 4) 10003
T_NUMBER_TAB(3, 4) 10004 T_NUMBER_TAB(2, 3)
10005 T_NUMBER_TAB(1, 2, 4) 10006
T_NUMBER_TAB(3, 4) 10007 T_NUMBER_TAB(2)
CAST converts one built-in data type or
collection-typed value into another built-in data
type or collection-typed value.
21Step 3 Simple tab_to_string Function
- CREATE OR REPLACE TYPE t_number_tab AS TABLE OF
NUMBER - CREATE OR REPLACE FUNCTION tab_to_string
- (
- p_number_tab IN
t_number_tab, - p_delimiter IN VARCHAR2
DEFAULT ', - ) RETURN VARCHAR2 IS
- l_string VARCHAR2(32767)
- BEGIN
- FOR i IN p_number_tab.FIRST ..
p_number_tab.LAST LOOP - IF i ! p_number_tab.FIRST THEN
- l_string l_string p_delimiter
- END IF
- l_string l_string
to_char(p_number_tab(i)) - END LOOP
- RETURN l_string
- END tab_to_string
22Step 3 tab_to_string(CAST(COLLECT))
- SELECT customer_id,
- tab_to_string(CAST(COLLECT(question_id) AS
- t_number_tab)) col
- FROM customer_inquiry
- GROUP BY customer_id
Customer_ID Question_ID 10001 1
10002 1 10002 2
10002 4 10003 3 10003
4 10004 2 10004 3
10005 1 10005 2
10005 4 10006 3 10006
4 10007 2
CUST_ID COLLECT(QUESTION_ID) -------
--------------------- 10001 1 10002 1,2,4
10003 3,4 10004 2,3 10005 1,2,4 10006
3,4 10007 2
The tab_to_string procedure converts a table of
numbers to a comma-separated VARCHAR2.
23Method 2 Putting it all together
- SELECT SUBSTR(col,1,10) questions,
- COUNT()
- FROM (
- SELECT customer_id,
- FROM answers
- GROUP BY customer_id
- )
- GROUP BY col
tab_to_string( CAST(
COLLECT(question_id)
AS t_number_tab
) ) col
Questions IDs Customer Count 1
1 1,2,4
2 3,4 2 2,3
1 2 1
24Method 3 XML (The Flying Spontinalli)
- XML functions
- Convert traditional table data into XML
- Inquire upon XML data and fragments
- Operate on XML data and fragments
- Convert XML data back to character data type
- CURSOR function Converts a sub-query into a REF
CURSOR
25Method 3 The Query
- SELECT REPLACE(REPLACE(REPLACE(
- questions,'lt/Qgt'C
HR(10)'ltQgt',',' - ),'ltQgt',NULL
- ),'lt/Qgt',NULL
- ) questions,
- COUNT() the_count
- FROM (
- SELECT DISTINCT customer_id,
EXTRACT (
SYS_XMLGEN(seq)
,'/SEQ/XMLTYPE/ROW/Q'
questions
).getstringval()
FROM ( SELECT customer_id,
XMLSEQUENCE
(
CURSOR
(
SELECT
question_id Q
FROM TEST t2
WHERE customer_id t.customer_id
)
) seq
FROM TEST t ) ) GROUP BY
questions
26Step 1 CURSOR and XMLSEQUENCE
CUST SEQ ----- ------------------------------ 100
01 XMLSEQUENCETYPE(XMLTYPE( ltROWgt
ltQgt1lt/Qgt lt/ROWgt
)) 10002 XMLSEQUENCETYPE(XMLTYPE( ltROWgt
ltQgt1lt/Qgt lt/ROWgt ),
XMLTYPE( ltROWgt ltQgt2lt/Qgt
lt/ROWgt ), XMLTYPE( ltROWgt
ltQgt4lt/Qgt lt/ROWgt
- SELECT customer_id,
- XMLSEQUENCE(
- CURSOR(
- SELECT question_id Q
- FROM TEST t2
- WHERE customer_id
t.customer_id - )
- ) seq
- FROM TEST t
The CURSOR function converts a sub-query into a
REF CURSOR. In this case, XMLSEQUENCE requires a
REF CURSOR.
The XMLSEQUENCE operator is used to split
multi-value results from XMLTYPE queries into
multiple rows.
27Step 2 SYS_XMLGen and EXTRACT
- SELECT DISTINCT customer_id,
- EXTRACT(
- SYS_XMLGEN(seq),'/S
EQ/XMLTYPE/ROW/Q' - ).getstringval ()
questions - FROM (
- SELECT customer_id,
- XMLSEQUENCE(
- CURSOR(
- SELECT
question_id Q - FROM TEST
t2 - WHERE
customer_id t.customer_id - )
- ) seq
- FROM TEST t
- )
The SYS_XMLGen function takes an expression that
evaluates to a particular row and column of the
database, and returns an instance of type XMLType
containing an XML document
Applying EXTRACT to an XMLType value extracts the
node or a set of nodes from the document
identified by the XPath expression. The method
getStringVal() retrieves the text from the
XMLType instance
28Step 2 SYS_XMLGen and EXTRACT
- SELECT DISTINCT customer_id,
- EXTRACT(
- SYS_XMLGEN(seq),'/S
EQ/XMLTYPE/ROW/Q' - ).getstringval ()
questions -
CUST SEQ ----- ------------------------------ 100
02 XMLSEQUENCETYPE(XMLTYPE( ltROWgt
ltQgt1lt/Qgt lt/ROWgt ),
XMLTYPE( ltROWgt ltQgt2lt/Qgt
lt/ROWgt ), XMLTYPE( ltROWgt
ltQgt4lt/Qgt lt/ROWgt
CUST QUESTIONS ----- ------------------------- 10
001 ltQgt1lt/Qgt 10002 ltQgt1lt/QgtltQgt2lt/QgtltQgt4lt/Qgt 10003
ltQgt3lt/QgtltQgt4lt/Qgt 10004 ltQgt2lt/QgtltQgt3lt/Qgt 10005
ltQgt1lt/QgtltQgt2lt/QgtltQgt4lt/Qgt 10006 ltQgt3lt/QgtltQgt4lt/Qgt 10
007 ltQgt2lt/Qgt
The SYS_XMLGen function takes an expression that
evaluates to a particular row and column of the
database, and returns an instance of type XMLType
containing an XML document
Applying EXTRACT to an XMLType value extracts the
node or a set of nodes from the document
identified by the XPath expression. The method
getStringVal() retrieves the text from the
XMLType instance
29Method 3 Back to the Query
- SELECT REPLACE(REPLACE(REPLACE(
- questions,'lt/Qgt'CHR(10)'ltQgt',
',' - ),'ltQgt',NULL
- ),'lt/Qgt',NULL
- ) questions,
- COUNT() the_count
- FROM (
- SELECT DISTINCT customer_id,
Questions IDs Cust Cnt 1
1 1,2,4
2 3,4 2
2,3 1
2 1
EXTRACT (
SYS_XMLGEN(seq)
,'/SEQ/XMLTYPE/ROW/Q'
questions
).getstringval()
FROM ( SELECT customer_id,
XMLSEQUENCE
(
CURSOR
(
SELECT
question_id Q
FROM TEST t2
WHERE customer_id t.customer_id
)
) seq
FROM TEST t ) ) GROUP BY
questions
30Method 4 MODEL (Rob van Wijk)
- SELECT q "Questions",
- COUNT() "Customer Count"
- FROM (
- SELECT SUBSTR(q,2) q,
- rn
- FROM a
- )
- WHERE rn 1
- GROUP BY q
MODEL PARTITION BY (cust_id)
DIMENSION BY (ROW_NUMBER() OVER
(PARTITION BY cust_id ORDER BY
quest_id DESC) rn) MEASURES
(CAST(quest_id AS varchar2(20)) q)
RULES ( qany ORDER BY rn
DESC qcv()1 ',' qcv()
)
31Method 4 The MODEL Portion of the Query
- MODEL PARTITION BY (cust_id)
- DIMENSION BY (ROW_NUMBER() OVER
- (PARTITION BY cust_id
ORDER BY quest_id DESC) rn) - MEASURES (CAST(quest_id AS
varchar2(20)) q) - RULES (
- qany ORDER BY rn DESC
qcv()1 ',' qcv() - )
The MODEL clause enables you to create a
multidimensional array by mapping the columns of
a query into three groups partitioning,
dimension, and measure columns
All text on this page from Oracle Database
Data Warehousing Guide
32Method 4 Dissecting the MODEL Clause
- MODEL PARTITION BY (cust_id)
- DIMENSION BY (ROW_NUMBER() OVER
- (PARTITION BY cust_id
ORDER BY quest_id DESC) rn) - MEASURES (CAST(quest_id AS
varchar2(20)) q) - RULES (
- qany ORDER BY rn DESC
qcv()1 ',' qcv() - )
The MODEL clause enables you to create a
multidimensional array by mapping the columns of
a query into three groups partitioning,
dimension, and measure columns
PARTITION columns define the logical blocks of
the result set in a way similar to the partitions
of the analytical functions. Rules in the MODEL
clause are applied to each partition independent
of other partitions
All text on this page from Oracle Database
Data Warehousing Guide
33Method 4 Dissecting the MODEL Clause
- MODEL PARTITION BY (cust_id)
- DIMENSION BY (ROW_NUMBER() OVER
- (PARTITION BY cust_id
ORDER BY quest_id DESC) rn) - MEASURES (CAST(quest_id AS
varchar2(20)) q) - RULES (
- qany ORDER BY rn DESC
qcv()1 ',' qcv() - )
The MODEL clause enables you to create a
multidimensional array by mapping the columns of
a query into three groups partitioning,
dimension, and measure columns
PARTITION columns define the logical blocks of
the result set in a way similar to the partitions
of the analytical functions. Rules in the MODEL
clause are applied to each partition independent
of other partitions
DIMENSION columns define the multi-dimensional
array and are used to identify cells within a
partition. By default, a full combination of
dimensions should identify just one cell in a
partition
All text on this page from Oracle Database
Data Warehousing Guide
34Method 4 Dissecting the MODEL Clause
- MODEL PARTITION BY (cust_id)
- DIMENSION BY (ROW_NUMBER() OVER
- (PARTITION BY cust_id
ORDER BY quest_id DESC) rn) - MEASURES (CAST(quest_id AS
varchar2(20)) q) - RULES (
- qany ORDER BY rn DESC
qcv()1 ',' qcv() - )
The MODEL clause enables you to create a
multidimensional array by mapping the columns of
a query into three groups partitioning,
dimension, and measure columns
PARTITION columns define the logical blocks of
the result set in a way similar to the partitions
of the analytical functions. Rules in the MODEL
clause are applied to each partition independent
of other partitions
DIMENSION columns define the multi-dimensional
array and are used to identify cells within a
partition. By default, a full combination of
dimensions should identify just one cell in a
partition
MEASURES are equivalent to the measures of a fact
table in a star schema.
All text on this page from Oracle Database
Data Warehousing Guide
35Method 4 Dissecting the MODEL Clause
- MODEL PARTITION BY (cust_id)
- DIMENSION BY (ROW_NUMBER() OVER
- (PARTITION BY cust_id
ORDER BY quest_id DESC) rn) - MEASURES (CAST(quest_id AS
varchar2(20)) q) - RULES (
- qany ORDER BY rn DESC
qcv()1 ',' qcv() - )
The MODEL clause enables you to create a
multidimensional array by mapping the columns of
a query into three groups partitioning,
dimension, and measure columns
PARTITION columns define the logical blocks of
the result set in a way similar to the partitions
of the analytical functions. Rules in the MODEL
clause are applied to each partition independent
of other partitions
DIMENSION columns define the multi-dimensional
array and are used to identify cells within a
partition. By default, a full combination of
dimensions should identify just one cell in a
partition
MEASURES are equivalent to the measures of a fact
table in a star schema
RULES are used to manipulate the measure values
of the cells in the multi-dimensional array
defined by partition and dimension columns
All text on this page from Oracle Database
Data Warehousing Guide
36Method 4 Dissecting the MODEL Clause
- quest_id ROW_NUMBER
- Cust ID CV() (rn) Q
- ------- ---- ------- ------
- 10001 1 1 ,1
- 10002 1 3 ,1
- 10002 2 2 ,1,2
- 10002 4 1 ,1,2,4
- 10003 3 2 ,3
- 10003 4 1 ,3,4
- 10004 2 2 ,2
- 10004 3 1 ,2,3
- 10005 1 3 1
- 10005 2 2 ,1,2
- 10005 4 1 ,1,2,4
- 10006 3 2 ,3
- 10006 4 1 ,3,4
- 10007 2 1 ,2
PARTITION BY (cust_id)
DIMENSION BY (ROW_NUMBER() OVER (PARTITION
BY cust_id ORDER BY quest_id DESC) rn)
MEASURES (CAST(quest_id AS
varchar2(20)) q)
RULES ( qany ORDER BY rn DESC
qcv(rn)1 ',' qcv(rn) ) Example
q2 q3,q2 NULL,3 q1
q2,q1 ,3,4
37Method 4 Back to the Query
Questions IDs Customer Count 1
1 1,2,4
2 3,4 2 2,3
1 2 1
- SELECT q "Questions",
- COUNT() "Customer Count"
- FROM (
- SELECT SUBSTR(q,2) q,
- rn
- FROM a
- )
- WHERE rn 1
- GROUP BY q
MODEL PARTITION BY (cust_id)
DIMENSION BY (ROW_NUMBER() OVER
(PARTITION BY cust_id ORDER BY
quest_id DESC) rn) MEASURES
(CAST(quest_id AS varchar2(20)) q)
RULES ( qany ORDER BY rn
DESC qcv()1 ',' qcv()
)
38Method 5 The Pipelined Function (michaels)
- Oracle Table Functions produce a collection of
rows that can be consumed by a query much like a
table. - Rows from a collection returned by a table
function can also be PIPELINED or returned as
they are produced instead of in a complete set
upon function completion. - Two supported approached for Pipelining
- Interface method
- PL/SQL method
39Method 5 The Query
- SELECT COLUMN_VALUE "Questions",
- COUNT () "Customer count"
- FROM TABLE (f ())
- GROUP BY COLUMN_VALUE
Oracle Table Functions produce a collection of
rows that can be consumed by a query much like a
table.
40Method 5 The Pipelined Function
- CREATE OR REPLACE FUNCTION f
- RETURN SYS.dbms_debug_vc2coll PIPELINED
- AS
- l_c1 VARCHAR2 (20)
- l_c2 PLS_INTEGER
- BEGIN
- FOR c IN
- (SELECT a.,
- COUNT () OVER (PARTITION BY
customer_id) cnt, - ROW_NUMBER () OVER (PARTITION BY
customer_id - ORDER BY question_id)
rn - FROM a
- ORDER BY customer_id, question_id)
- LOOP
41Method 5 The Pipelined Function continued
- LOOP
- IF l_c2 c.customer_id OR l_c2 IS NULL THEN
- l_c1 l_c1 c.question_id ','
- l_c2 c.customer_id
- IF c.cnt c.rn THEN
- PIPE ROW (RTRIM (l_c1, ','))
- l_c1 NULL
- l_c2 NULL
- END IF
- END IF
- END LOOP
- Â
- RETURN
- END f
42Method 5 The Pipelined Function
- SELECT COLUMN_VALUE "Questions",
- COUNT () "Customer count"
- FROM TABLE (f ())
- GROUP BY COLUMN_VALUE
Questions IDs Customer Count 1
1 1,2,4
2 3,4 2 2,3
1 2 1
43So many choices, so little time
- If all these queries provide the same results,
which one should be chosen? - Query cost information was added to this post -
yet another topic! - The results
- Michaels PIPELINED Function
- Rob's MODEL
- Nicolas' HIERARCHY 1
- Nicolas' HIERARCHY 2
- Greg's COLLECT
- Warren/devmiral's HIERARCHY
- Michaels'/Gregs XML
44Not done yet! Even More Solutions
- XML combined with COLLECT
- Bit Pattern
- User-defined Aggregate Functions (ODCIAggregate
Interface) - Old-school Oracle 7 solution
45Wow, All of These Topics in a Single Thread!
- Hierarchical Queries
- SYS_CONNECT_BY_ROOT
- Analytic Functions
- COLLECT
- CAST
- CURSOR
- XML Functions
- MODEL Clause
- Pipelined Functions
- Bit Pattern Techniques
- User-defined Aggregates
- Explain Plans/Query Costs
- BUTNever underestimate the value of using
widely-understood and accepted Oracle database
concepts - The experts here used this thread to demonstrate
alternate technologies only and never advocated
these rather esoteric solutions
46Jumping in the Pool Forum-Decorum
- Dont demand urgent help. In fact, dont demand
anything from this all-volunteer community - Search for an answer first
- Use the proper code notation tags reformatting
queries is a pain - preThis is code text/pre
- Dont flame the Gurusyou will likely get
scorched! - If you use information from the Forums on your
Blog or anywhere else, please reference your
source - Dont be intimidated. If you dont understand an
answer, request clarification - Thank your responders
47Wrap-Up
- The Oracle SQL and PL/SQL Forum has 64K topics
with almost 350k posts - Other active Forums include
- Database-General
- App Server
- J-Developer
- Forms
- OWB
- More!
- Take advantage of the experts including many
Oracle Aces! - Learn something new
- Become a regular contributor!
48Acknowledgements
- Oracle Database Data Warehousing Guide 10gR2
- Oracle Database SQL Reference 10gR2
- Oracle XML DB Developer's Guide 11gR1
- OTN - Getting into SQL/XML - Tim Quinlan
- http//www.oracle-base.com
- The OTN SQL and PL/SQL Forum
49(No Transcript)
50Thank You for attending!
Thank You for attending!
- Greg Pike
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- Piocon Technologies
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