M05640020220124029M0564 PSBD Pert 15-16 Additional DML VerMA10mei13

7/30/2019 M05640020220124029M0564 PSBD Pert 15-16 Additional DML VerMA10mei13

1/97


2/97

SQL : Data Manipulation

Week 8-11

Course Name : Introduction of Database System

Year : 2012


3/97

Outline Material

Purpose and importance of SQL.

How to retrieve data from database using SELECT and:

Use compound WHERE conditions.

Sort query results using ORDER BY.

Use aggregate functions.

Group data using GROUP BY and HAVING.

Use subqueries.

Join tables together.

Perform set operations (UNION, INTERSECT, EXCEPT).

How to update database using INSERT, UPDATE, and DELETE.

Pearson Education 2009


4/97

Objectives of SQL

Ideally, database language should allow user to: create the database and relation structures;

perform insertion, modification, deletion of data fromrelations;

perform simple and complex queries. Must perform these tasks with minimal user effort

and command structure/syntax must be easy tolearn.

It must be portable.



5/97

Objectives of SQL

SQL is a transform-oriented language with 2 major

components:

A DDL for defining database structure and controlling

access data.

A DML for retrieving and updating data.

SQL is relatively easy to learn:

it is non-procedural - you specify whatinformation you

require, rather than howto get it;

it is essentially free-format.



6/97

Objectives of SQL

Consists of standard English words:

1) CREATE TABLE Staff(staffNo VARCHAR(5),

lName VARCHAR(15),

salary DECIMAL(7,2));2) INSERT INTO Staff VALUES (SG16,Brown, 8300);

3) SELECT staffNo, lName, salary

FROM Staff

WHERE salary > 10000;



7/97

Objectives of SQL

Can be used by range of users including DBAs,

management, application developers, and other

types of end users.

An ISO standard now exists for SQL, making it boththe formal and de facto standard language for

relational databases.



8/97

Writing SQL Commands

SQL statement consists ofreserved wordsand user-

def ined words.

Reserved words are a fixed part of SQL and must be

spelt exactly as required and cannot be split across

lines.

User-defined words are made up by user and

represent names of various database objects such

as relations, columns, views.



9/97


10/97

Writing SQL Commands

Use extended form of BNF notation:

- Upper-case letters represent reserved words.

- Lower-case letters represent user-defined

words.- | indicates a cho iceamong alternatives.

- Curly braces indicate a required element.

- Square brackets indicate an op t ional element.

- indicates op t ional repet i t ion(0 or more).



11/97

Literals

Literals are constants used in SQL statements.

All non-numeric literals must be enclosed in single

quotes (e.g. London).

All numeric literals must not be enclosed in quotes

(e.g. 650.00).



12/97

SELECT Statement

SELECT [DISTINCT | ALL]

{* | [columnExpression [AS newName]] [,...] }

FROM TableName [alias] [, ...]

[WHERE condition]

[GROUP BY columnList][HAVING condition]

[ORDER BY columnList]

Order of the clauses cannot be changed.

Only SELECT and FROM are mandatory.



13/97

SELECT Statement

SELECT Specifies which columns are to appear in output.

FROM Specifies table(s) to be used.

WHERE Filters rows or Join Condition.

GROUP BY Forms groups of rows with same column value.

HAVING Filters groups subject to some condition.

ORDER BY Specifies the order of the output.



14/97

Entity Relationship Diagram

Bina Nusantara University

14


15/97

Example:

SELECT t.Kode_Pelanggan AS [Kode Pelanggan], Nama_Pelanggan, Jenis_Pembayaran,COUNT(*) AS Total_Jumlah_Transaksi

FROMPelanggan p, Transaksi t

WHEREp.Kode_Pelanggan=t.Kode_Pelanggan ANDMONTH(Tgl_Transaksi)=3 OR

MONTH(Tgl_Transaksi)=4 ANDYEAR(Tgl_Transaksi)=2013

GROUP BYt.Kode_Pelanggan, Nama_Pelanggan, Jenis_Pembayaran

HAVINGCOUNT(*)>=2ORDER BYt.Kode_Pelanggan, Jenis_Pembayaran DESC;

Menampilkan: Kode_Pelanggan (diberi alias [Kode Pelanggan] supaya dapat mengandung spasi

dan diawali dengan alias tabel Transaksi untuk mengatasi ambiguitas 1 atribut ada di 2 tabel yang

berbeda), Nama_Pelanggan, Jenis_Pembayaran, total jumlah transaksi yang dilakukan (diberi

alias Total_Jumlah_Transaksi).

Berasal dari tabel: Pelanggan (diberi alias p) dan Transaksi (diberi alias t)

Kondisi Filter/Join: Join antara tabel Pelanggan dan Transaksi, Filtertransaksi yang terjadi pada

bulan Maret 2013 sampai April 2013

Dikelompokkan berdasarkan: Kode_Pelanggan, Nama_Pelanggan, Jenis_Transaksi

Filter Group: yang memenuhi COUNT(*)>=2

Diurutkan berdasarkan: (1) Kode_Pelanggan secara menaik lalu (2) Jenis_Pembayaran secara

menurun


16/97

Kode_Pelanggan

Nama_Pelanggan

A001 Aditya

B001 Budiman

D001 Dani

Kode_Transaksi Tgl_Transaksi Jenis_Pembayaran Jenis_Transaksi

Kode_Pelanggan

0103130001 1 March 2013 Cash A001

0203130001 2 March 2013 Cash B001

0203130002 2 March 2013 Cash A001

0303130001 3 March 2013 Cash A001

0104130001 1 April 2013 Credit Card A001

0104130002 1 April 2013 Debit Card B001




17/97

Tgl_Transaksi Jenis_Pembayaran Kode_Pelanggan

1 March 2013 Cash A001

2 March 2013 Cash B001



1 April 2013 Credit Card A001

1 April 2013 Debit Card B001

2 April 2013 Debit Card B001

2 April 2013 Credit Card A001

Kode Pelanggan Nama_Pelanggan Jenis_Pembayaran Total_Ju

A001 Aditya Cash 3

A001 Aditya Credit Card 2

B001 2 Maret 2013 Cash 1

B001 3 Maret 2013 Debit Card 2

Kode Pelanggan Nama_Pelanggan Jenis_Pembayaran Total_Jumlah_Transaksi

A001 Aditya Cash 3

A001 Aditya Credit Card 2

B001 3 Maret 2013 Debit Card 2

Keterangan: Sebelum HAVING COUNT(*)>=2 diterapkan

Keterangan: Setelah HAVING COUNT(*)>=2 diterapkan


18/97

Example 1 All Columns, All RowsMenampilkan semua detail/atribut dari tabel Transaksi:

SELECT Kode_Transaksi, Tgl_Transaksi, Jenis_Pembayaran, Jenis_Transaksi, Kode_Pelanggan

FROM Transaksi;

Dapat menggunakan *sebagai

pengganti

penulisan semua

kolom/atribut:

SELECT *

FROM Transaksi;


Kode_Transaksi Tgl_Transaksi Jenis_Pembayaran Jenis_Transaksi Kode_Pelanggan

0103130001 1 March 2013 Cash A001

0203130001 2 March 2013 Cash B001

0203130002 2 March 2013 Cash A001

0303130001 3 March 2013 Cash A001






19/97

Example 2 Specific Columns, All RowsMenampilkan kode transaksi, tanggal transaksi dan jenis pembayaran dari tabel transaksi

SELECT Kode_Transaksi, Tgl_Transaksi, Jenis_Pembayaran FROM Transaksi;


Kode_Transaksi Tgl_Transaksi Jenis_Pembayaran

0103130001 1 March 2013 Cash

0203130001 2 March 2013 Cash

0203130002 2 March 2013 Cash

0303130001 3 March 2013 Cash

0104130001 1 April 2013 Credit Card

0104130002 1 April 2013 Debit Card

0204130001 2 April 2013 Debit Card

0204130002 2 April 2013 Credit Card


20/97

Example 3 Use of DISTINCTMenampilkan kode pelanggan pada

tabel transaksi:

SELECT Kode_Pelanggan

FROM Transaksi;

Menghapus duplikasi dengan

menggunakan DISTINCT:

SELECT DISTINCT Kode_Pelanggan

FROM Transaksi;


Kode_Pelanggan

A001

B001

A001

A001

A001

B001

B001

A001

Kode_Pelanggan

A001

B001


21/97

Example 4 Calculated Fields

Menghasilkan sub total barang yang dibeli padadetail transaksi yang menampilkan kode transaksi,

kode produk, jumlah dan harga satuan.

SELECT Kode_Transaksi, Kode_Produk, Jumlah,Harga_Satuan, Jumlah*Harga_Satuan AS Sub_Total

FROM Detail_Transaksi;



22/97

Kode_Transaksi Kode_Produk Jumlah Harga_Satuan Sub_Total

0103130001 P0001 2 1000 2000

0203130001 P0001 1 1000 1000

0203130001 P0002 3 5000 15000

0203130002 P0002 5 5000 25000

0203130002 P0003 4 25000 100000

0303130001 P0001 3 1000 3000

0303130001 P0002 5 5000 25000

0303130001 P0003 1 25000 25000


23/97

Example 5 Comparison Search Condition

Menampilkan detail transaksi yang membeli produk dengan harga satuan lebih

besar dari 4000.

SELECT * FROM Detail_Transaksi

WHERE Harga_Satuan > 4000;


Kode_Transaksi Kode_Produk Jumlah Harga_Satuan

0203130001 P0002 3 5000

0203130002 P0002 5 5000

0203130002 P0003 4 25000

0303130001 P0002 5 5000

0303130001 P0003 1 25000


24/97

Example 6 Compound Comparison Search

ConditionMenampilkan transaksi dengan jenis pembayaran yang menggunakan Credit

Card atau Debit Card:

SELECT *

FROM Transaksi

WHERE Jenis_Pembayaran = Credit CardOR Jenis_Pembayaran = Debit Card;


Kode_Transaksi Tgl_Transaksi Jenis_Pembayaran Jenis_Transaksi Kode_Pelanggan






25/97

Example 7 Set MembershipMenampilkan transaksi dengan jenis pembayaran yang menggunakan

Credit Card atau Debit Card:

SELECT *

FROM Transaksi

WHERE Jenis_Pembayaran IN (Credit Card, Debit Card);

IN is more efficient when set contains many values.

There is a negated version (NOT IN).

Menampilkan transaksi dengan jenis pembayaran SELAIN Credit Card

atau Debit Card (yakni Cash):

SELECT *

FROM Transaksi

WHERE Jenis_Pembayaran NOT IN (Credit Card, Debit Card);



26/97

Example 8 Range Search ConditionMenampilkan detail transaksi yang membeli produk dengan harga

satuan antara 5000 dan 30000:

SELECT *

FROM Detail_Transaksi

WHERE Harga_Satuan BETWEEN 5000 AND 30000;

Could also write:

SELECT *

FROM Detail_TransaksiWHERE Harga_Satuan >=5000 AND Harga_Satuan


27/97

Example 8 Range Search ConditionMenampilkan detail transaksi yang membeli produk dengan harga

satuan diluar range 5000 dan 30000:

SELECT *


WHERE Harga_Satuan NOT BETWEEN 5000 AND 30000;

Could also write:

SELECT *

FROM Detail_TransaksiWHERE Harga_Satuan 30000;



28/97

Example 9 Pattern Matching

SQL has two special pattern matching symbols:

%: sequence of zero or more characters;

_ (underscore): any single character.

LIKE %Baby% means a sequence of characters of anylength containing Baby.

Menampilkan detail transaksi dengan kode transaksi

bernilai 0113 pada karakter 3 sampai dengan 6 (Januari

2013):

SELECT * FROM Detail_Transaksi

WHERE Kode_Transaksi LIKE '_ _ 0113%'



29/97

Example 9 Pattern MatchingMenampilkan semua produk yang mengandung kata 'Baby' pada namanya:

SELECT * FROM Produk

WHERE Nama_Produk LIKE %Baby%;

Baby Oil, Tissue for Baby, Zwitsal Baby Hair Lotion


Menampilkan semua produk yang berawalan kata 'Baby' pada namanya:


WHERE Nama_Produk LIKE Baby%;

Baby Oil, Baby Hair Lotion

Menampilkan semua produk yang berakhiran kata 'Baby' pada namanya:


WHERE Nama_Produk LIKE %Baby;

Tissue for Baby, Cuddle Warm Baby


30/97

Example 10 NULL Search Condition

Menampilkan transaksi yang dilakukan oleh selain Pelanggan,dimana atribut Kode_Pelanggan tidak ada isinya.

Have to test for null explicitly using special keywordIS NULL:

SELECT Kode_TransaksiFROM Transaksi

WHERE Kode_Pelanggan IS NULL;

Kode_Transaksi

0105130001Negated version (IS NOT NULL) can test for non-null

values.



31/97

Example 11 Single Column Ordering

Menampilkan semua produk diurutkan berdasarkan

harga secara menurun.

SELECT *

FROM Produk

ORDER BY Harga_Produk DESC;

ASC: menaik (ascending)

DESC: menurun (descending)Jika tidak dispesifikasikan, default-nya ascending



32/97

Example 12 Multiple Column Ordering

Menampilkan semua produk yang diurutkan

berdasarkan kode produk secara menaik kemudian

harga secara menurun:

SELECT *FROM Produk

ORDER BY Nama_Produk, Harga_Produk DESC;



33/97

SELECT Statement - Aggregates

ISO standard defines five aggregate functions:

COUNT returns number of values in specified column.

SUM returns sum of values in specified column.

AVG returns average of values in specified column.

MIN returns smallest value in specified column.

MAX returns largest value in specified column.



34/97


Each operates on a single column of a table and

returns a single value.

COUNT, MIN, and MAX apply to numeric and non-

numeric fields, but SUM and AVG may be used on

numeric fields only.

Apart from COUNT(*), each function eliminates nulls

first and operates only on remaining non-null

values.



35/97


COUNT(*) counts all rows of a table, regardless of

whether nulls or duplicate values occur.

Can use DISTINCT before column name to eliminate

duplicates.

DISTINCT has no effect with MIN/MAX, but may have

with SUM/AVG.



36/97


Aggregate functions can be used only in SELECTlist and in HAVING clause.

If SELECT list includes an aggregate function andthere is no GROUP BY clause, SELECT list cannotreference a column out with an aggregate function.For example, the following is illegal:

SELECT staffNo, COUNT(salary)FROM Staff;



37/97

37

Example 13 Use of

COUNT(*)Menampilkan ada berapa transaksi yang terjadi

pada bulan Maret 2013 dan April 2013

SELECT COUNT(*) AS myCount

FROM Transaksi

WHERE MONTH(Tgl_Transaksi) IN (3,4)

AND YEAR(Tgl_Transaksi)= 2013;


Kode_Transaksi Tgl_Transaksi ....

0103130001 1 March 2013

0203130001 2 March 2013

0203130002 2 March 2013

0303130001 3 March 2013

0104130001 1 April 2013

0104130002 1 April 2013

0204130001 2 April 2013

0204130002 2 April 2013

myCount

8


38/97

38

Example 14

Use of

COUNT(DISTINCT)Ada berapa pelanggan yang melakukantransaksi di bulan Maret 2013?

SELECT COUNT(DISTINCT

Kode_Pelanggan) AS myCount

FROM Transaksi

WHERE Tgl_Transaksi BETWEEN 1-March-2013

AND 31-March-2013;

Bagaimana hasilnya jika:

SELECT COUNT(Kode_Pelanggan) AS

myCount .........


Kode_Transaksi Tgl_Transaksi . Kode_Pelanggan

0103130001 1 March 2013 A001

0203130001 2 March 2013 B001

0203130002 2 March 2013 A001

0303130001 3 March 2013 A001

0104130001 1 April 2013 A001

0104130002 1 April 2013 B001

0204130001 2 April 2013 B001

0204130002 2 April 2013 A001

myCount

2


39/97

Example 15 Use of COUNT, SUM, MAX, MIN, AVG

Menampilkan jumlah transaksi, total jumlah produk, harga satuan terbesar, harga satuan

terkecil, dan rata-rata harga satuan dari produk dengan harga satuan lebih besar dari

4000 dari Tabel DETAIL TRANSAKSI.

SELECT COUNT(Kode_Transaksi) AS JmlTransaksi, SUM(Jumlah) AS JmlProduk,

MAX(Harga_Satuan) AS HargaMax, MIN(Harga_Satuan) AS HargaMin,

AVG(Harga_Satuan) AS HargaAvg


WHERE Harga_Satuan > 4000;


Kode_Transaksi

Kode_Produk

Jumlah

Harga_Satuan

0203130001 P0002 3 5000

0203130002 P0002 5 5000

0203130002 P0003 4 25000

0303130001 P0002 5 5000

jmlTransaksi jmlProduk HargaMax HargaMin HargaAvg

5 18 25000 5000 13000


40/97

SELECT Statement - Grouping

Use GROUP BY clause to get sub-totals.

SELECT and GROUP BY closely integrated: each

item in SELECT list must be single-valued per

group, and SELECT clause may only contain:

column names

aggregate functions

constants

expression involving combinations of the above.



41/97

SELECT Statement - Grouping

All column names in SELECT list must appear in

GROUP BY clause unless name is used only in an

aggregate function.

If WHERE is used with GROUP BY, WHERE is

applied first, then groups are formed from remaining

rows satisfying predicate.

ISO considers two nulls to be equal for purposes of

GROUP BY.



42/97

Example 16 Use of GROUP BYMenampilkan jumlah jenis produk, grand total transaksi yang dikelompokkanberdasarkan kode transaksi:

SELECT Kode_Transaksi,COUNT(Kode_Produk) AS myCount,

SUM(Jumlah*Harga_Satuan) AS mySum


GROUP BY Kode_Transaksi

ORDER BY Kode_Transaksi;


Kode_Transaksi Kode_Produk

Jumlah Harga_Satuan

Sub_Tot

0103130001 P0001 2 1000 2

0203130001 P0001 1 1000 1

0203130001 P0002 3 5000 15

0203130002 P0002 5 5000 25

0203130002 P0003 4 25000 100

0303130001 P0001 3 1000 3

0303130001 P0002 5 5000 25

Kode_Transaksi myCount mySum

0103130001

1 2000

0203130001

2 16000

0203130002

2 125000

0303130001

3 53000


43/97

Restricted Groupings HAVING clause

HAVING clause is designed for use with GROUP BYto restrict groups that appear in final result table.

Similar to WHERE, but WHERE filters individual

rows whereas HAVING filters groups.

Column names in HAVING clause must also appear

in the GROUP BY list or be contained within an

aggregate function.



44/97

Example 17 Use of HAVINGMenampilkan jumlah jenis produk, grand total transaksi yang dikelompokkan berdasarkan kodetransaksi serta minimal membeli 2 jenis produk:

SELECT Kode_Transaksi,

COUNT(Kode_Produk) AS myCount,

SUM(Jumlah*Harga_Satuan) AS mySum


GROUP BY Kode_Transaksi

HAVING COUNT(Kode_Produk)>=2

ORDER BY Kode_Transaksi;


Kode_Transaksi Kode_Produk

Jumlah Harga_Satuan

Sub_Total

0103130001 P0001 2 1000 200

0203130001 P0001 1 1000 100

0203130001 P0002 3 5000 1500

0203130002 P0002 5 5000 2500

0203130002 P0003 4 25000 10000

0303130001 P0001 3 1000 300

0303130001 P0002 5 5000 2500

Kode_Transaksi myCount mySum

0203130001

2 16000

0203130002

2 125000

0303130001

3 53000


45/97

Subqueries

Some SQL statements can have a SELECTembedded within them.

A subselect can be used in WHERE and HAVING

clauses of an outer SELECT, where it is called a

subqueryornested query.

Subselects may also appear in INSERT, UPDATE,

and DELETE statements.



46/97

Example 18 Subquery with EqualityMenampilkan transaksi yang dilakukan oleh pelanggan yang bernama Budiman. Dimana

equality (=) hanya mengembalikan 1 nilai pada sub query.

SELECT*

FROM Transaksi

WHERE Kode_Pelanggan=

(SELECT Kode_PelangganFROM Pelanggan

WHERE Nama_Pelanggan = Budiman);

Inner SELECT mencari Kode_Pelanggan untuk Pelanggan bernama Budiman(B001).Outer SELECT kemudian menampilkan transaksi yang dilakukan oleh Budiman. Outer

SELECT menjadi: SELECT * FROM Transaksi

WHERE Kode_Pelanggan = B001;


Kode_Pelanggan Nama_Pelanggan

A001 Aditya

B001 Budiman

D001 Dani


47/97

Example 18 Subquery with Equality

Inner SELECT finds Kode_Pelanggan for branch at163 Main St(B003).

Outer SELECT then becomes:

SELECT staffNo, fName, lName, positionFROM Staff

WHERE branchNo = B003;


Kode_Transkasi Tgl_Transaksi Jenis_Pembayaran Jenis_Transaksi Kode_Pelanggan

0203130001 2 March 2013 Cash B001




48/97

Subquery Rules

ORDER BY clause may not be used in a subquery (although itmay be used in outermost SELECT).

Subquery SELECT list must consist of a single column name

or expression, except for subqueries that use EXISTS.

By default, column names refer to table name in FROM clause

of subquery. Can refer to a table in FROM using an alias.

When subquery is an operand in a comparison, subquery

must appear on right-hand side.

A subquery may not be used as an operand in an expression.



49/97

Example 19 Nested subquery: use of IN

Menampilkan transaksi yang dilakukan oleh pelanggan yang namanya diawalidengan huruf A.

SELECT *

FROM Transaksi

WHERE Kode_PelangganIN

(SELECT Kode_Pelanggan

FROM Pelanggan

WHERE Nama_Pelanggan LIKE 'A%');

Jika Equality(=) hanya ada 1 nilai yang dikembalikan oleh sub query, sedangkan INbisa mengembalikan lebih dari 1 nilai.



50/97

EXISTS and NOT EXISTS

EXISTS and NOT EXISTS are for use only withsubqueries.

Produce a simple true/false result.

True if and only if there exists at least one row inresult table returned by subquery.

False if subquery returns an empty result table.

NOT EXISTS is the opposite of EXISTS.



51/97

EXISTS and NOT EXISTS

As (NOT) EXISTS check only for existence or non-existence of rows in subquery result table, subquery

can contain any number of columns.

Common for subqueries following (NOT) EXISTS tobe of form:

(SELECT * ...)



52/97

Example 20 Query using EXISTS

Menampilkan transaksi yang dilakukan oleh pelanggan yang namanya diawalidengan huruf A.

SELECT *

FROM Transaksi t

WHERE EXISTS

(SELECT *

FROM Pelanggan p

WHERE Nama_Pelanggan LIKE 'A%'

AND t.Kode_Pelanggan = p.Kode_Pelanggan);

Bisa juga ditulis menggunakan JOIN:

SELECT t.*FROM Transaksi t, Pelanggan p

WHERE Nama_Pelanggan LIKE 'A%'

AND t.Kode_Pelanggan = p.Kode_Pelanggan;



53/97

ANY and ALL

ANY and ALL may be used with subqueries thatproduce a single column of numbers.

With ALL, condition will only be true if it is satisfiedby allvalues produced by subquery.

With ANY, condition will be true if it is satisfied byanyvalues produced by subquery.

If subquery is empty, ALL returns true, ANY returnsfalse.

SOME may be used in place of ANY.



54/97

Example 21 Use of ANY/SOME

Tampilkan produk yang memiliki harga lebih besardari minimal salah satu harga satuan produk yang

dibeli pada tabel detail transaski.

SELECT *FROM Produk

WHERE Harga > SOME

(SELECT Harga_Satuan

FROM Detail_Transaksi);



55/97

Example 21 Use of ANY/SOME Inner query menghasilkan himpunan {1000, 5000, 25000} dan outer

query memilih Produk-Produk yang memiliki harga lebih besar dari

minimal salah satu nilai di himpunan tersebut.


Kode_Produk Nama_Produk Harga

P1 A 1000

P2 B 5000

P3 C 25000

P4 D 500

P5 E 30000

P6 F 10000

P7 G 2500

P8 H 27500


56/97

Example 21 Use of ANY/SOME Inner query menghasilkan himpunan {1000, 5000, 25000} dan outer

query memilih Produk-Produk yang memiliki harga lebih besar dari

minimal salah satu nilai di himpunan tersebut.



P2 B 5000

P3 C 25000

P5 E 30000

P6 F 10000

P7 G 2500

P8 H 27500


57/97

Example 22 Use of ALL

Tampilkan produk yang memiliki harga lebih besardari semua harga satuan produk yang dibeli pada

tabel detail transaski.

SELECT *

FROM Produk

WHERE Harga > ALL

(SELECT Harga_Satuan

FROM Detail_Transaksi);



P5 E 30000

P8 H 27500


58/97

Multi-Table Queries Can use subqueries provided result columns come from same table.

If result columns come from more than one table must use a join.

To perform join, include more than one table in FROM clause.

Use comma as separator and typically include WHERE clause to

specify join column(s).

Also possible to use an alias for a table named in FROM clause.

Alias is separated from table name with a space.

Alias can be used to qualify column names when there is ambiguity.



59/97

Example 23 Simple Join

Menampilkan pelanggan yang pernah melakukan transaksi

beserta kode dan tanggal transaksi.

SELECT p.Kode_Pelanggan AS [Kode Pelanggan],

Nama_Pelanggan, Kode_Transaksi, Tgl_Transaksi

FROM Pelanggan p, Transaksi t

WHERE p.Kode_Pelanggan = t.Kode_Pelanggan;

Only those rows from both tables that have identical values in

the Kode_Pelanggan columns (p.Kode_Pelanggan =t.Kode_Pelanggan) are included in result.

Equivalent to equi-join in relational algebra.



60/97

Example 23 Simple Join

Only those rows fromboth tables that have

identical values in the

Kode_Pelanggan

columns

(p.Kode_Pelanggan =t.Kode_Pelanggan)

are included in result. Equivalent to equi-

join in relationalalgebra.


Kode

Pelanggan

Nama_Pelanggan Kode_Transkasi Tgl_Transaksi

A001Aditya

0103130001 1 March 2013

B001Budiman

0203130001 2 March 2013

A001Aditya

0203130002 2 March 2013

A001Aditya

0303130001 3 March 2013

A001 Aditya 0104130001 1 April 2013

B001Budiman

0104130002 1 April 2013

B001Budiman

0204130001 2 April 2013


61/97

Alternative JOIN Constructs

SQL provides alternative ways to specify joins:

FROM Pelanggan p JOIN Transaksi t ON p.Kode_Pelanggan =

t.Kode_Pelanggan

FROM Pelanggan JOIN Transaksi USING Kode_Pelanggan

FROM Pelanggan NATURAL JOIN Transaksi

In each case, FROM replaces original FROM and WHERE.

However, first produces table with two identical

Kode_Pelanggancolumns.



62/97

Example 24 Three Table Join

Menampilkan kode transaksi, tanggal transaksi, kode produk,nama produk, jumlah produk yang dibeli.

SELECT t.Kode_Transaksi AS [Kode Transaksi], Tgl_Transaksi,p.Kode_Produk AS [Kode Produk], Nama_Produk, Jumlah

FROM Transaksi t, Detail_Transaksi dt, Produk p

WHERE t.Kode_Transaksi = dt.Kode_TransaksiAND dt.Kode_Produk = p.Kode_Produk

ORDER BY t.Kode_Transaksi, p.Kode_Produk;

Alternative formulation for FROM and WHERE:

FROM (Transaksi t JOIN Detail_Transaksi dt USINGKode_Transaksi) AS

tdt JOIN Produk p USING Kode_Produk



63/97

Example 24 Three Table Join


Kode_Transkasi

Tgl_Transaksi

Kode_ProdukNama_Produk

Jumlah

01031300011 March 2013

P0001A

2

02031300012 March 2013

P0001A

1

02031300012 March 2013

P0002B

3

02031300022 March 2013

P0002B

5

02031300022 March 2013

P0003C

4

03031300013 March 2013

P0001A

3

03031300013 March 2013

P0002B

5

3 March 2013 C


64/97

Outer Joins

If one row of a joined table is unmatched, row isomitted from result table.

Outer join operations retain rows that do not satisfy

the join condition.

Consider following tables:



65/97

Outer Joins

The (inner) join of these two tables:

SELECT b.*, p.*

FROM Branch1 b, PropertyForRent1 p

WHERE b.bCity = p.pCity;



66/97

Outer Joins

Result table has two rows where cities are same.

There are no rows corresponding to branches in

Bristol and Aberdeen.

To include unmatched rows in result table, use an

Outer join.



67/97

Example 25 Left Outer Join

List branches and properties that are in same cityalong with any unmatched branches.

SELECT b.*, p.*

FROM Branch1 b LEFT JOIN

PropertyForRent1 p ON b.bCity = p.pCity;



68/97

Example 25 Left Outer Join

Includes those rows of first (left) table unmatchedwith rows from second (right) table.

Columns from second table are filled with NULLs.



69/97

Example 26 Right Outer Join

List branches and properties in same city and anyunmatched properties.

SELECT b.*, p.*

FROM Branch1 b RIGHT JOINPropertyForRent1 p ON b.bCity = p.pCity;



70/97

Example 26 Right Outer Join

Right Outer join includes those rows of second(right) table that are unmatched with rows from first

(left) table.

Columns from first table are filled with NULLs.



71/97

Example 27 Full Outer Join

List branches and properties in same city and anyunmatched branches or properties.

SELECT b.*, p.*

FROM Branch1 b FULL JOINPropertyForRent1 p ON b.bCity = p.pCity;



72/97

Example 27 Full Outer Join

Includes rows that are unmatched in both tables.

Unmatched columns are filled with NULLs.



73/97

Union, Intersect, and Difference (Except)

Can use normal set operations of Union,Intersection, and Difference to combine results oftwo or more queries into a single result table.

Union of two tables, A and B, is table containing allrows in either A or B or both.

Intersection is table containing all rows common toboth A and B.

Difference is table containing all rows in A but not inB.

Two tables must be union com patib le.



74/97

Union, Intersect, and Difference (Except)

Format of set operator clause in each case is:

op [ALL] [CORRESPONDING [BY {column1 [,

...]}]]

If CORRESPONDING BY specified, set operationperformed on the named column(s).

If CORRESPONDING specified but not BY clause,

operation performed on common columns.

If ALL specified, result can include duplicate rows.



75/97

Union, Intersect, and

Difference (Except)



76/97

Example 28 Use of UNION

List all cities where there is either a branch office ora property.

(SELECT city

FROM Branch

WHERE city IS NOT NULL) UNION(SELECT city

FROM PropertyForRent

WHERE city IS NOT NULL);



77/97


Or

(SELECT *

FROM Branch

WHERE city IS NOT NULL)

UNION CORRESPONDING BY city(SELECT *

FROM PropertyForRent

WHERE city IS NOT NULL);



78/97


Produces result tables from both queries andmerges both tables together.



79/97

Example 30 Use of INTERSECT

List all cities where there is both a branch office anda property.

(SELECT city FROM Branch)

INTERSECT(SELECT city FROM PropertyForRent);



80/97


Or

(SELECT * FROM Branch)

INTERSECT CORRESPONDING BY city

(SELECT * FROM PropertyForRent);



81/97


Could rewrite this query without INTERSECToperator:

SELECT b.city

FROM Branch b PropertyForRent pWHERE b.city = p.city;

Or:

SELECT DISTINCT city FROM Branch b

WHERE EXISTS(SELECT * FROM PropertyForRent p

WHERE p.city = b.city);



82/97

Example 31 Use of EXCEPT

List of all cities where there is a branch office but noproperties.

(SELECT city FROM Branch)

EXCEPT

(SELECT city FROM PropertyForRent); Or

(SELECT * FROM Branch)

EXCEPT CORRESPONDING BY city

(SELECT * FROM PropertyForRent);



83/97

Example 31 Use of EXCEPT

Could rewrite this query without EXCEPT:

SELECT DISTINCT city FROM Branch

WHERE city NOT IN

(SELECT city FROM PropertyForRent); Or

SELECT DISTINCT city FROM Branch b

WHERE NOT EXISTS

(SELECT * FROM PropertyForRent p

WHERE p.city = b.city);



84/97

INSERT

INSERT INTO TableName [ (columnList) ]VALUES (dataValueList)

co lumnLis tis optional; if omitted, SQL assumes a

list of all columns in their original CREATE TABLEorder.

Any columns omitted must have been declared asNULL when table was created, unless DEFAULT wasspecified when creating column.



85/97

INSERT

dataValueListmust match co lumnLis tas follows: number of items in each list must be same;

must be direct correspondence in position of items in two

lists;

data type of each item in dataValueList must be

compatible with data type of corresponding column.



86/97

Example 32 INSERT VALUES

Insert a new row into Staff table supplying data forall columns.

INSERT INTO Staff

VALUES (SG16, Alan, Brown, Assistant, M, Date1957-05-25, 8300, B003);



87/97

Example 33 INSERT using Defaults

Insert a new row into Staff table supplying data forall mandatory columns.

INSERT INTO Staff (staffNo, fName, lName,

position, salary, branchNo)

VALUES (SG44,Anne,Jones,Assistant, 8100, B003);

Or

INSERT INTO Staff

VALUES (SG44, Anne, Jones, Assistant,NULL, NULL, 8100, B003);



88/97

INSERT SELECT

Second form of INSERT allows multiple rows to becopied from one or more tables to another:

INSERT INTO TableName [ (columnList) ]

SELECT ...



89/97

Example 34 INSERT SELECT

Assume there is a table StaffPropCount thatcontains names of staff and number of properties

they manage:

StaffPropCount(staffNo, fName, lName,

propCnt)

Populate StaffPropCount using Staff and

PropertyForRent tables.



90/97


INSERT INTO StaffPropCount(SELECT s.staffNo, fName, lName, COUNT(*)

FROM Staff s, PropertyForRent p

WHERE s.staffNo = p.staffNo

GROUP BY s.staffNo, fName, lName)UNION

(SELECT staffNo, fName, lName, 0

FROM Staff

WHERE staffNo NOT IN(SELECT DISTINCT staffNo

FROM PropertyForRent));



91/97


If second part of UNION is omitted, excludes thosestaff who currently do not manage any properties.



92/97

UPDATE

UPDATE TableNameSET columnName1 = dataValue1

[, columnName2 = dataValue2...]

[WHERE searchCondition]

TableNamecan be name of a base table or anupdatable view.

SET clause specifies names of one or morecolumns that are to be updated.



93/97

UPDATE

WHERE clause is optional: if omitted, named columns are updated for all rows in

table;

if specified, only those rows that satisfy searchCondi t ion

are updated.

New dataValue(s)must be compatible with data

type for corresponding column.



94/97

Example 35/36 UPDATE All Rows

Give all staff a 3% pay increase.

UPDATE StaffSET salary = salary*1.03;

Give all Managers a 5% pay increase.

UPDATE StaffSET salary = salary*1.05

WHERE position = Manager;



95/97

Example 37 UPDATE Multiple Columns

Promote David Ford (staffNo=SG14) to Managerand change his salary to 18,000.

UPDATE Staff

SET position = Manager, salary = 18000

WHERE staffNo = SG14;

SET: new valuesWHERE: conditions or old values



96/97

DELETE

DELETE FROM TableName[WHERE searchCondition]

TableNamecan be name of a base table or an

updatable view.

searchCondi t ionis optional; if omitted, all rows are

deleted from table. This does not delete table. If

search_condi t ionis specified, only those rows that

satisfy condition are deleted.



97/97

Example 38/39 DELETE Specific Rows

Delete all viewings that relate to property PG4.

DELETE FROM Viewing

WHERE propertyNo = PG4;

Delete all records from the Viewing table.

DELETE FROM Viewing;

Date post:	14-Apr-2018
Category:	Documents
Upload:	muhammad-faisal-rahman
View:	216 times
Download:	0 times

M05640020220124029M0564 PSBD Pert 15-16 Additional DML VerMA10mei13

Documents