Lab_03 - data warehouse

DATA WAREHOUSE
DW_Lab03.doc
GUIA PRACTICA DE LABORATORIO #3
PRÁCTICA 1: QUERYS
1. Retornar solo las columnas (au_fname, au_lname, phone) de authors que viven en
California y no tienen de apellido McBadden. Se ha adicionado un encabezado de
Columna.
SELECT au_fname, au_lname, phone AS Telephone
FROM authors
WHERE state = 'CA' and au_lname <> 'McBadden'
ORDER BY au_lname ASC, au_fname ASC
2. Retornar el total year-to-date sales y el monto que le corresponde a author y
publisher.
SELECT ytd_sales AS Sales, authors.au_fname + ' '+ authors.au_lname AS Author,
ToAuthor = (ytd_sales*royalty)/100, ToPublisher = ytd_sales-(ytd_sales*royalty)/100
FROM titles INNER JOIN titleauthor
ON titles.title_id = titleauthor.title_id INNER JOIN authors ON titleauthor.au_id =
authors.au_id
ORDER BY Sales DESC, Author ASC
3. Este ejercicio crea la tabla temporal #coffeetabletitles en la tempdb. (#)
DROP TABLE #coffeetabletitles
SELECT * INTO #coffeetabletitles
FROM titles
WHERE price < $20
SELECT name FROM tempdb..sysobjects WHERE name LIKE '#c%'
4. Uso de FUNCIONES AGREGADAS y condiciones sobre agrupaciones
SELECT pub_id, SUM(advance), AVG(price)
FROM titles
WHERE price >= $5
GROUP BY pub_id
HAVING SUM(advance) > $15000
AND AVG(price) < $20AND pub_id > '0800'
ORDER BY pub_id
5. Uso de Indices para optimizar las busquedas
SELECT au_lname, au_fname, phone
FROM authors WITH (INDEX(aunmind))
WHERE au_lname = 'Smith'
Lic. Hugo Guerrero
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DATA WAREHOUSE
DW_Lab03.doc
PRÁCTICA 2: OPTIMIZACIONES
1. Funciones MIN/MAX
select MinPrice=min(price)
,Maxprice=max(price)
from titles
--Vrs
select MinPrice=(select min(price) from titles)
,Maxprice=(select max(price) from titles)
2. COUNT Eficientes
count(*)
--Vrs
count(column_name)
3. EXISTS Vrs. COUNT
if(select count(*) from titles
where type='business')>0
print 'Tu tienes libros de negocio'
--Vrs
if EXISTS(select * from titles
where type='business')
print 'Tu tienes libros de negocio'
4. Comparaciones Eficientes
select * from titles where price>=11
--Vrs
select * from titles where price>10.99
5. Eficiencia a travez de muchas consultas relacionadas
select d.stor_id, d.ord_num, d.qty, t.title
from titles t, sales d
where t.title_id=d.title_id
and d.title_id='BU1032'
--Vrs
declare @title varchar(20)
select @title=title
from titles
where title_id='BU1032'
select stor_id, ord_num, qty,@title
from sales
where title_id='BU1032'
Lic. Hugo Guerrero
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DATA WAREHOUSE
DW_Lab03.doc
PRÁCTICA 3: FUNCIONES
1. Funciones de Fecha
getdate, datename, datepart, datediff, dateadd
2. Funciones de Cadena
char_length, len, left, right, ltrim, rtrim, substring, upper, lower
3. ISNULL
select price
,price=isnull(price,0.0)
from titles
4. Funciones Matematicas
abs, ceiling, floor, sign, rand
5. Funciones Caracteristicas (efecto Matriz)
Numeric:
X=Y
1-abs(sign(X-Y))
X>Y
1-sign(1-sign(X-Y))
String:
X=Y
charindex(X,Y)*charindex(Y,X)
Date:
X=Y
1-abs(sign(datediff(dd,Y,X)))
X>Y
1-sign(1-sign(datediff(dd,Y,X)))
Lic. Hugo Guerrero
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