OOW19 - Ten Amazing SQL features

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Copyright © 2019 Oracle and/or its affiliates.
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Connor McDonald
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Stuff
youtube bit.ly/youtube-connor
blog bit.ly/blog-connor
twitter bit.ly/twitter-connor
400+ posts mainly on database & development
250 technical videos, new uploads every week
rants and raves on tech and the world :-)
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etc...
facebook bit.ly/facebook-connor
linkedin bit.ly/linkedin-connor
instagram bit.ly/instagram-connor
slideshare bit.ly/slideshare-connor
8 8https://asktom.oracle.com
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WHY ?
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why talk about SQL ?
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it is old !
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why talk about SQL # 1
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NoSQL
non relational
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why talk about SQL # 2
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developers love cool stuff
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MICROSERVICES
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SQL is microservices !
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"fine-grained to perform a single function"
"Each service is ... minimal, and complete"
https://en.wikipedia.org/wiki/Microservices
select COUNT(*)
from PEOPLE
where GENDER = 'MALE'
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even cooler stuff
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API
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SQL is entirely APIs !
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"By abstracting the underlying implementation"
"describes the expected behaviour ...
but can have multiple implementations"
https://en.wikipedia.org/wiki/Application_programming_interface
select NAME, STREET_NO, ZIP_CODE
from PEOPLE p,
ADDRESS a
where p.AGE > 50
and p.ADDRESS_ID = a.ADDRESS_ID;
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key point
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this session is not about ...
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being a smart-ass
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we can do anything ...
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SQL> with x( s, ind ) as
2 ( select sud, instr( sud, '.' )
3 from ( select replace(replace(
4 replace(replace(:board,'-'),'|'),' '),chr(10)) sud
5 from dual )
6 union all
7 select substr(s,1,ind-1)||z||substr(s,ind+1)
8 , instr(s,'.',ind+1)
9 from x
10 , ( select to_char( rownum ) z
11 from dual connect by rownum <= 9 ) z
12 where ind > 0
13 and not exists (
14 select null
15 from ( select rownum lp from dual
16 connect by rownum <= 9 )
17 where z = substr(s,trunc((ind-1)/9)*9+lp,1)
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18 or z = substr(s,mod(ind-1,9)-8+lp*9,1)
19 or z = substr(s,mod(trunc((ind-1)/3),3)*3
20 +trunc((ind-1)/27)*27+lp
21 +trunc((lp-1)/3)*6,1)
22 )
23 ),
24 result as (
25 select s
26 from x
27 where ind = 0 )
28 select
29 regexp_replace(substr(s,(idx-1)*9+1,9),
30 '(...)(...)(...)',
31 '1|2|3')||
32 case when mod(idx,3)=0 then chr(10)||rpad('-',11,'-') end soln
33 from result,
34 ( select level idx
35 from dual
36 connect by level <= 9 )
Ack: Anton Scheffer,
https://technology.amis.nl
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SQL> variable board varchar2(1000)
SQL> begin :board :=
2 '53.|.7.|...
3 6..|195|...
4 .98|...|.6.
5 -----------
6 8..|.61|..3
7 4..|8.3|..1
8 7..|.2.|..6
9 -----------
10 .6.|...|28.
11 ...|419|..5
12 ...|.8.|.79
13 ';
14 end;
5 3 7
6 1 9 5
9 8 6
8 6 1 3
4 8 3 1
7 2 6
6 2 8
4 1 9 5
8 7 9
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SOLUTION
-----------
534|678|912
672|195|348
198|342|567
-----------
859|761|423
426|853|791
713|924|856
-----------
961|537|284
287|419|635
345|286|179
-----------
sud.sql
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100%
% of developers that
will need to solve Sudoku
as part of their job
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100%
% of developers that need
to get real work done
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real work
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1
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some controversy...
DBA
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Public
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Public
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DBA friendship is important
oc00.sql
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totals / subtotals
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"Employee salary list,
plus department total,
plus grand total"
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SQL> select empno, ename, sal, deptno from emp
2 order by deptno;
EMPNO ENAME SAL DEPTNO
---------- ---------- ---------- ----------
7782 CLARK 2450 10
7839 KING 5000 10
7934 MILLER 1300 10
...
7900 JAMES 950 30
7698 BLAKE 2850 30
7654 MARTIN 1250 30
SQL> select deptno,
2 sum(sal)
3 from emp
4 group by deptno
5 order by deptno;
DEPTNO SUM(SAL)
---------- ----------
10 8750
20 10875
30 9400
SQL> select sum(sal) from emp;
SUM(SAL)
----------
29025
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from 3 to 2
rollup
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SQL> select empno, ename, sal, deptno from emp
2 order by deptno;
EMPNO ENAME SAL DEPTNO
---------- ---------- ---------- ----------
7782 CLARK 2450 10
7839 KING 5000 10
7934 MILLER 1300 10
...
7900 JAMES 950 30
7698 BLAKE 2850 30
7654 MARTIN 1250 30
SQL> select deptno,
2 sum(sal)
3 from emp
4 group by rollup(deptno)
5 order by deptno;
DEPTNO SUM(SAL)
---------- ----------
10 8750
20 10875
30 9400
29025
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still messy...
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EMPNO SAL DEPTNO
---------- ---------- ----------
7782 2450 10
7839 5000 10
7934 1300 10
7566 2975 20
7902 3000 20
7876 1100 20
7369 800 20
DEPTNO SUM(SAL)
---------- ----------
10 8750
20 10875
30 9400
29025
7782 2450 10
7839 5000 10
7934 1300 10
7566 2975 20
10 8750
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from 2 to 1
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SQL> select deptno,
2 nvl2(rownum,max(empno),null) empno,
3 nvl2(rownum,max(ename),null) ename,
4 sum(sal)
5 from emp
6 group by rollup(deptno,rownum)
7 order by deptno,empno;
DEPTNO EMPNO ENAME SUM(SAL)
---------- ---------- ---------- ----------
10 7782 CLARK 2450
10 7839 KING 5000
10 7934 MILLER 1300
10 8750
20 7369 SMITH 800
20 7566 JONES 2975
...
30 7900 JAMES 950
30 9400
29025
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all totals are possible
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SQL> select deptno,job,sum(sal) from scott.emp
2 group by CUBE(deptno,job)
3 order by deptno,job;
DEPTNO JOB SUM(SAL)
---------- --------- ----------
10 CLERK 1300
10 MANAGER 2450
10 PRESIDENT 5000
10 8750
20 ANALYST 6000
20 CLERK 1900
20 MANAGER 2975
20 10875
30 CLERK 950
30 MANAGER 2850
30 SALESMAN 5600
30 9400
ANALYST 6000
CLERK 4150
MANAGER 8275
PRESIDENT 5000
SALESMAN 5600
29025
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totally customisable
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SQL> select deptno, job, mgr, sum(sal) from emp
2 group by grouping sets (
3 (deptno),
4 (job,mgr), () ) ;
DEPTNO JOB MGR SUM(SAL)
---------- --------- ---------- ----------
CLERK 7902 800
PRESIDENT 5000
CLERK 7698 950
CLERK 7788 1100
CLERK 7782 1300
SALESMAN 7698 5600
MANAGER 7839 8275
ANALYST 7566 6000
10 8750
20 10875
30 9400
29025
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error logging
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SQL> insert into MY_TABLE
2 select *
3 from MY_HUGE_GREAT_FAT_TABLE;MY_HUGE_GREAT_FAT_TABLE;
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2 select *
3 from MY_HUGE_GREAT_FAT_TABLE;
Elapsed: 06:12:34.00
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2 select *
3 from MY_HUGE_GREAT_FAT_TABLE;
Elapsed: 06:12:34.00
ERROR at line 1:
ORA-01847: day of month must be between 1 and last day of month
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and then we do this :-)
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SQL> select count(*) from MY_TABLE;
COUNT(*)
----------
0
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what we would like
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keep successful rows
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skip / bypass bad rows
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hard
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2 select *
3 from MY_HUGE_GREAT_FAT_TABLE
4 where "not a duplicate"
5 and "datatypes are ok"
6 and "foreign keys are ok"
7 and "check constraints are ok"
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SQL> exec DBMS_ERRLOG.CREATE_ERROR_LOG('EMP')
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ERR$_EMP
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DBMS_ERRLOG.CREATE_ERROR_LOG (
dml_table_name IN VARCHAR2,
err_log_table_name IN VARCHAR2 := NULL,
err_log_table_owner IN VARCHAR2 := NULL,
...
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SQL> desc ERR$_EMP
Name Null? Type
----------------------------- -------- ----------------
ORA_ERR_NUMBER$ NUMBER
ORA_ERR_MESG$ VARCHAR2(2000)
ORA_ERR_ROWID$ ROWID
ORA_ERR_OPTYP$ VARCHAR2(2)
ORA_ERR_TAG$ VARCHAR2(2000)
EMPNO VARCHAR2(4000)
ENAME VARCHAR2(4000)
JOB VARCHAR2(4000)
MGR VARCHAR2(4000)
HIREDATE VARCHAR2(4000)
SAL VARCHAR2(4000)
COMM VARCHAR2(4000)
DEPTNO VARCHAR2(4000)
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example
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add to EMP from NEW_DATA
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SQL> select * from NEW_DATA;
EMPNO SAL DEPTNO
---------- ---------- ----------
1000 5000 20
100X 3550 10
2000 2500 50
7934 4000 20
non-numeric
no dept 50
duplicate
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SQL> exec dbms_errlog.create_error_log('EMP');
PL/SQL procedure successfully completed.
SQL> insert into EMP (empno,sal,deptno)
2 select empno,sal,deptno
3 from NEW_DATA
4 LOG ERRORS REJECT LIMIT UNLIMITED;
1 row created.
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SQL> select ORA_ERR_OPTYP$ op, ORA_ERR_MESG$, EMPNO
2 from ERR$_EMP
OP ORA_ERR_MESG$ EMPNO
-- ------------------------------------------------------------ -----
I ORA-01722: invalid number 100X
I ORA-02291: integrity constraint (SCOTT.FK_DEPTNO) violated 2000
I ORA-00001: unique constraint (SCOTT.PK_EMP) violated 7934
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partitioned outer join
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SQL> select *
2 from timeslots;
HR
--
8
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SQL> select *
2 from bookings;
HR ROOM WHO
------- ---------- -------
8 Room2 PETE
9 Room1 JOHN
11 Room1 MIKE
14 Room2 JILL
15 Room2 JANE
16 Room1 SAM
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bookings by hour
conventional outer join
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SQL> SELECT hrs.hr, t1.room, t1.who
2 from timeslots hrs
3 left outer join bookings t1
4 on hrs.hr = t1.hr
5 order by 1
HR ROOM WHO
------- ---------- ----------
8 Room2 PETE
9 Room1 JOHN
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11 Room1 MIKE
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13
14 Room2 JILL
15 Room2 JANE
16 Room1 SAM
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bookings by hour per room
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HR ROOM WHO
------- ---------- ----------
8 Room2 PETE
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10
11
12
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14 Room2 JILL
15 Room2 JANE
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HR ROOM WHO
------- ---------- ----------
8
9 Room1 JOHN
10
11 Room1 MIKE
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14
15
16 Room1 SAM
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SQL> select *
2 from timeslots;
HR
--
8
9
10
11
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x "Room 1"
x "Room 2"
...
x "Room n"
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partitioned outer join
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SQL> SELECT hrs.hr, t1.room, t1.who
2 FROM bookings t1
3 PARTITION BY (t1.room)
4 RIGHT OUTER JOIN timeslots ON (hrs.hr = t1.hr)
5 order by 1,2
HR ROOM WHO
--------- ---------- ----------
8 Room1
9 Room1 JOHN
10 Room1
11 Room1 MIKE
12 Room1
13 Room1
14 Room1
15 Room1
16 Room1 SAM
8 Room2 PETE
9 Room2
10 Room2
11 Room2
12 Room2
13 Room2
14 Room2 JILL
15 Room2 JANE
16 Room2
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subquery factoring
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common table expressions
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WITH clause
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WITH last_hire AS
(
select deptno, max(hiredate)
from emp
group by deptno
)
select * from last_hire;
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"who cares?....... more code, same result"
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why is it cool ?
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good solution metaphor
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relational is a rigorous model ...
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relational is the dominant model ...
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relational ... can be complicated
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not our fault
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Codd & Date
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"data is represented as mathematical n-ary
relations, an n-ary relation being a subset of the
Cartesian product of n domains."
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?
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procedural world
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step by step
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"First, get the total salary paid by each department,
then get the average of these totals,
then list those departments above that average"
SQL ?
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"First, get the total salary paid by department...
SQL> WITH dept_salaries AS (
2 SELECT dname, SUM(sal) dept_sal
3 FROM emp e, dept d
4 WHERE e.deptno = d.deptno
5 GROUP BY dname),
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"...then get the average of these totals...
6 avg_sal AS ( SELECT AVG(dept_sal) avsal
7 FROM dept_salaries)
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"...then list those departments above average."
8 SELECT * FROM dept_salaries d, avg_sal a
9 WHERE d.dept_sal > a.avsal
10 ORDER BY d.dname;
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SQL> WITH dept_salaries AS (
2 SELECT dname, SUM(sal) dept_sal
3 FROM emp e, dept d
4 WHERE e.deptno = d.deptno
5 GROUP BY dname),
6 avg_sal AS ( SELECT AVG(dept_sal) avsal
7 FROM dept_salaries)
8 SELECT * FROM dept_salaries d, avg_sal a
9 WHERE d.dept_sal > a.avsal
10 ORDER BY d.dname;
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programmer's approach....
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... relational solution
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the "finishing touches"
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everyone loves JSON
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recall: partitioned outer join
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SQL> with raw_data as (
2 select
3 hrs.hr,
4 t1.room,
5 t1.who
6 from bookings t1
7 partition by (t1.room)
8 right outer join hrs
9 on (hrs.hr = t1.hr)
10 order by
11 hr, room
12 )
13 select
14 json_arrayagg(
15 json_object(key room||to_char(hr) value who )
16 order by hr ) as meetings
17 from raw_data ;
[{"Room1-08":null},
{"Room1-09":"JOHN"},
{"Room1-10":null},
{"Room1-11":"MIKE"},
{"Room1-12":null},
...
...
{"Room2-14":"JILL"},
{"Room2-15":null},
{"Room2-16":"JANE"}]
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speaking of procedural to relational
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scalar queries
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SQL> select
2 ( select dname
3 from dept
4 where deptno = e.deptno ) dname,
5 decode(empno, 7499,
6 ( select max(sal) from emp ),
7 -1)
8 from
9 ( select * from emp
10 where sal > 0 ) e
11 where
12 ( select max(hiredate) from emp ) < sysdate
13 /
scalar
anywhere an
expression could be
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turn procedural into "relational"
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List all persons in the STAFF table plus their salary calculated
based on CLASS_TYPE column value:
= ‘T’ (temp worker) salary is FIXED_PRICE from
PART_TIME_PACKAGE table
= ‘C’ (contractor) salary is the HRS * HRLY_RATE from
CONTRACT_PACKAGE table
= ‘P’ (permanent) salary is the ANNUAL_SAL + BONUS from
PERM_PACKAGE table
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different table per row
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4 begin
5 for i in ( select * from staff ) loop
6 if i.class_type = 'T' then -- part time
7 select fixed_price
8 into v_sal
9 from part_time_package
10 where id = i.class_id;
11 elsif i.class_type = 'C' then -- contractors
12 select hrs * hrly_rate
13 into v_sal
14 from contract_package
16 elsif i.class_type = 'P' then -- permanent
17 select annual_sal + bonus
18 into v_sal
19 from perm_package
21 end if;
22 dbms_output.put_line(rpad(i.name,20)||lpad(v_sal,10));
23 end loop;
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SQL can still do it
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SQL> select s.name,
2 case class_type
3 when 'T' then (
4 select fixed_price
5 from part_time_package
6 where id = s.class_id )
7 when 'C' then (
8 select hrs * hrly_rate
9 from contract_package
11 when 'P' then (
12 select annual_sal + bonus
13 from perm_package
15 end sal
16 from staff s;
Scalar subquery
NAME SAL
------------------------------ -------
JOHN SMITH 123.45
JOE BLOGGS 2435.54
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"big deal..."
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subquery caching
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transposition
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rows to columns, colums to rows
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"I need sales by product
for each quarter....now"
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SQL> select product,
2 trunc(txn_date,'Q') mth,
3 sum(quantity) total
4 from SALES
5 group by product,trunc(txn_date,'Q')
6 order by 1,2;
PRODUCT MTH TOTAL
-------------------- --- ----------
CHAINSAW JAN 251473
CHAINSAW APR 254830
CHAINSAW JUL 251994
CHAINSAW OCT 243748
HAMMER JAN 249889
HAMMER APR 256566
HAMMER JUL 252992
HAMMER OCT 249104
SCREW DRIVER JAN 245988
SCREW DRIVER APR 249219
SCREW DRIVER JUL 252128
SCREW DRIVER OCT 244721
SPADE JAN 242434
SPADE APR 254090
SPADE JUL 259613
...
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"That’s wrong!...surely you know
I wanted it ACROSS the page"
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pivot clause
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SQL> select *
2 from (select product,
3 trunc(txn_date,'Q') mth,
4 quantity
5 from sales )
6 pivot( sum(quantity) for mth in
7 ( 'JAN',
8 'APR',
9 'JUL',
10 'OCT') )
11 order by 1
12 /
PRODUCT 'JAN' 'APR' 'JUL' 'OCT'
-------------------- ---------- ---------- ---------- ----------
CHAINSAW 251473 254830 251994 243748
HAMMER 249889 256566 252992 249104
SCREW DRIVER 245988 249219 252128 244721
SPADE 242434 254090 259613 248428
WHEEL BARROW 243899 249327 252296 254137
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unpivot as well
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8
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most of us know about analytics
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SQL> select row_number() OVER ( order by sal )
2 from emp
3 ...
https://bit.ly/analytic_sql
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"Show me lowest salary for each department..."
SQL> select deptno, min(sal)
2 from emp
3 group by deptno;
"...and I need to know who has that lowest salary"
SQL> select deptno, empno, min(sal)
2 from emp
3 group by deptno;
ORA-00979: not a GROUP BY expression
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KEEP extension
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SQL> select deptno, min(sal),
2 min(empno)
3 KEEP ( dense_rank FIRST order by sal) empno
4 from emp
5 group by deptno;
DEPTNO MIN(SAL) EMPNO
---------- ---------- ----------
10 1300 7934
20 800 7369
30 950 7900
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every system ...
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... I've worked on
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struggles with cAsE
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no correlation ☺
but its my fault
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SQL> select surname
2 from names;
SURNAME
------------------------------
jones
brown
SMITH
sigh...
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SQL> select initcap(surname)
2 from names;
SURNAME
------------------------------
Jones
Brown
Smith
Mcdonald
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and it just gets worse...
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SQL> select *
2 from customers
3 where cust_name = 'ADAMS';
COUNTRY CREATED CUST_NAME
------------ --------- ------------
AUS 07-NOV-16 ADAMS
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SQL> select *
2 from customers
3 where upper(cust_name) = 'ADAMS';
------------ --------- ------------
AUS 07-NOV-16 Adams
AUS 07-NOV-16 ADAMS
AUS 07-NOV-16 adams
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SQL> select * from customers
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SQL> select column_name
2 from user_ind_columns
3 where index_name = 'CUST_IX';
COLUMN_NAME
------------------------------
CUST_NAME
-------------------------------------------------------
| Id | Operation | Name | Rows | Bytes |
-------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 152 |
|* 1 | TABLE ACCESS FULL| CUSTOMERS | 1 | 152 |
-------------------------------------------------------
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SQL> create index cust_ix
2 on customers ( cust_name );
Index created.
SQL> create index cust_ix2
2 on customers ( upper(cust_name) );
Index created.
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DML slower
more contention
more redo/undo
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"not my problem"
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SQL> alter table customers shrink space;
*
ERROR at line 1:
ORA-10631: SHRINK clause should not be specified
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a better way
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column level collation
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?
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200
SQL> CREATE TABLE CUSTOMERS
2 (
3 COUNTRY VARCHAR2(128),
4 CREATED DATE,
5 CUST_NAME VARCHAR2(150) COLLATE BINARY_CI
6 );
Table created.
"case insenstive"
201
SQL> create index cust_ix
2 on customers ( cust_name);
Index created.
SQL> set autotrace traceonly explain
-----------------------------------------------------------------
| Id | Operation | Name | Rows |
-----------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 |
| 1 | TABLE ACCESS BY INDEX ROWID BATCHED| CUSTOMERS | 1 |
|* 2 | INDEX RANGE SCAN | CUST_IX | 1 |
-----------------------------------------------------------------
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"what is so special about that?"
203
------------ --------- ----------------
AUS 07-NOV-16 Adams
AUS 08-NOV-16 ADAMS
AUS 09-NOV-16 adams
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binary_ci
------------ --------- ------------
AUS 07-NOV-16 Adams
AUS 08-NOV-16 ADAMS
AUS 09-NOV-16 adams
205
binary_ai
------------ --------- -----------
AUS 07-NOV-16 Adams
AUS 08-NOV-16 ADAMS
AUS 09-NOV-16 adams
AUS 10-NOV-16 adáms
adáms
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column | table | user
207
SQL> alter table people default collation binary_ai;
new columns only
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10
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query block naming
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C#, C++ ESB Tuxedo
Weblogic
Stored
Procedure
211
for (int i = 0; i < WinningCombinations.Count; ++i)
{
if (WinningCombinations[i].Investment > 0 &&
WinningCombinations[i].PrimaryDividend > MinDividendDeadHeat)
{
maxDivisor =
Math.Max(maxDivisor, WinningCombinations[i].Divisor);
}
}
for (int i = 0; i < WinningCombinations.Count; ++i)
{
if (WinningCombinations[i].Investment > 0 &&
WinningCombinations[i].PrimaryDividend > MinDividendDeadHeat)
{
WinningCombinations[i].Divisor =
maxDivisor / WinningCombinations[i].Divisor;
sumNewDivisors += WinningCombinations[i].Divisor;
}
}
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no comments
212
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"C# is self-documenting"
215
SQL can be complex
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SQL should "self document"
217
query blocks = self-documenting SQL
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select emp.*
from emp,
( select trunc(hiredate,'YYYY'), max(empno) empno
from emp
where empno > 0
group by trunc(hiredate,'YYYY') ) x,
( select deptno, avg(sal)
from emp
group by deptno ) y
where x.empno = emp.empno
and y.deptno = emp.deptno
219
Id | Operation | Name |
----------------------------------------------|
0 | SELECT STATEMENT | |
1 | HASH JOIN | |
2 | TABLE ACCESS BY INDEX ROWID | EMP |
3 | NESTED LOOPS | |
4 | VIEW | |
5 | SORT GROUP BY | |
6 | TABLE ACCESS BY INDEX ROWID| EMP |
7 | INDEX FULL SCAN | E2 |
8 | INDEX RANGE SCAN | E1 |
9 | VIEW | |
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?
select emp.*
from emp,
( select trunc(hiredate,'YYYY'), max(empno) empno
from emp
where empno > 0
( select deptno, avg(sal)
from emp
group by deptno ) y
Id | Operation | Name |
----------------------------------------------|
1 | HASH JOIN | |
4 | VIEW | |
9 | VIEW | |
221
select emp.*
from emp,
( select /*+ QB_NAME(YR_HIRE) */
trunc(hiredate,'YYYY'), max(empno) empno
from emp
where empno > 0
( select /*+ QB_NAME(AV_SAL) */
deptno, avg(sal)
from emp
group by deptno ) y
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Id | Operation | Name | Query Block
----------------------------------------------|--------------
1 | HASH JOIN | |
4 | VIEW | |
9 | VIEW | |
SEL$1
SEL$1
AV_SAL
AV_SAL
AV_SAL
AV_SAL
SEL$1
YR_HIRE
YR_HIRE
YR_HIRE
YR_HIRE
223
last
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225
225
224
225

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"talking" to your database
... makes it faster
227
example
226
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228
STORES
CUSTOMERS
SALES
229
select prod_id, max(amount)
from stores st,
customers c,
sales s
where s.cust_id = c.cust_id(+)
and c.store_id = st.store_id
and s.amount > 10
group by prod_id
hash outer join ?
nested loop ?
STORES first ?
sort merge ?
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---------------------------------------------------
| Id | Operation | Name | Rows |
---------------------------------------------------
| 0 | SELECT STATEMENT | | 100 |
| 1 | HASH GROUP BY | | 100 |
|* 2 | HASH JOIN | | 990K |
| 3 | NESTED LOOPS SEMI | | 5000 |
| 4 | TABLE ACCESS FULL| CUSTOMERS | 5000 |
|* 5 | INDEX UNIQUE SCAN| STORE_IX | 50 |
|* 6 | TABLE ACCESS FULL | SALES | 990K |
---------------------------------------------------
231
can we do better ?
add indexes ?
rewrite query ?
result cache ?
materialized view ?
230
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232
share your knowledge with the db
oc04.sql
233
wrap up
232
233

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234
SQL
235
very cool
234
235

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236
very powerful
237
less code
236
237

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never too early to start
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Proven Ways to Make Applications Slower and Less Secure [THT4796]
Tuesday, September 17, 04:30 PM - 04:50 PM, The Exchange - Theater 3
The Best Oracle Database Feature Ever Invented [THT4798]
Wednesday, September 18, 10:15 AM - 10:35 AM, The Exchange - Theater 3
Flashback - Not Just for DBAs
Wednesday, September 18, 04:00 PM - 04:45 PM, Moscone South - Room 306
PL/SQL: Still the Best Data Access Language
Thursday, September 19, 12:15 PM - 01:00 PM, Moscone South - Room 155A
241
Have a great OpenWorld !
youtube youtube.com/c/ConnorMcDonaldOracle
blog connor-mcdonald.com
twitter @connor_mc_d
240
241

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