SQL Cookbook

Simon P. Chappell writes "One of the staples of corporate I.S. development is processing data, and increasingly these days that data lives in a relational database. The lingua franca of relational database programming is the Structured Query Language (SQL), often pronounced "sequel". Many programmers find that the basics of SQL are easy to learn, but after that, it tends to get complicated. Enter the SQL Cookbook from O'Reilly." Read the rest of Simon's review.

SQL Cookbook
author	Anthony Molinaro
pages	595 (9 page index)
publisher	O'Reilly
rating	8/10
reviewer	Simon P. Chappell
ISBN	0596009763
summary	If you need help working with a database, this is the book for you.

The book is not for beginners and makes no efforts to teach any SQL. It concentrates purely on building on the base level of SQL knowledge that most programmers have. If you know the basics: Create, Read, Update and Delete (an unfortunate, yet memorable acronym) but rarely go beyond that, this book is for you. I know that I fall into this target market.

The point of the cookbook is that you need to get something done and you need to get it done sooner rather than later. Now, most of us can figure out most things given enough time, but in the real world, we rarely have enough time. The cookbooks objective is to save you time by giving you a successful approach that you could have figured out eventually anyway.

If you've previously read any other technology cookbook from O'Reilly, then you already know the structure of the recipes. For those new to the O'Reilly cookbook format, it's actually fairly straightforward. Each recipe starts out with a problem statement. Recipe one in chapter one, titled "Retrieving all Rows and Columns from a Table" has the problem statement "You have a table and want to see all of the data in it." Nice and clear. Then comes the solution. Naturally, for this problem statement we end up with a SELECT that looks like this:

select * from emp

Then the recipe has a discussion section where the solution is explained in more detail and the reasoning behind it is provided. For recipe one, the discussion explores the trade-offs between using the "*" to signify all columns versus naming each column explicitly.

The chapter structure through the book is very much one of building on the previous material. The first chapter starts with the fundamentals, the retrieving of records and then chapter two takes over with sorting the results of your query, while chapter three looks at using multiple tables.

Chapter four covers inserting, updating and deleting records. After that it's back into the world of queries, with chapter five exploring metadata queries for those times when you need to know just a little more about what's going on under the covers. Chapter six looks at working with Strings, a much harder topic than it would seem at first thought. Chapter seven addresses working with numbers and chapter eight does the same for date arithmetic with chapter nine bringing more understanding to general date manipulation. Chapter ten looks at working with ranges.

Chapter eleven dives into advanced searching in preparation for chapter twelve's information on reporting and (data) warehousing. Hierarchical queries are always challenging, so they're reserved for chapter thirteen. Finally, chapter fourteen is titled "Odds 'n' Ends" and is a general catch-all for some pretty advanced, but very infrequent problems.

I guess you either like the recipe approach or not. I love it, so I'm listing it as something to like about this book. The recipes are very well explained and while each one presents only one approach, where there are obviously multiple options, the discussion takes care to explain the reasoning behind the selection.

The writing is clear and the explanations are well laid out. Both the SQL code and the query results are presented well and are easy to read.

A very important part of the book is that it covers SQL variations for Oracle, IBM's DB2, Microsoft SQL Server and the open-source databases PostgresSQL and MySQL. Each of the recipes includes solutions for each of the five databases. While SQL is a standard, there seems to be some very relaxed definitions of full adherence to that standard; hence the book has to present up to five solutions for each problem.

Many of the recipes are advanced. While the front of the book has the entry level material, it ramps up in complexity pretty quickly. For some of us with very straightforward SQL knowledge, some of the recipes are going to take a while to fully understand and be able to use.

Many of the recipes are obviously oriented towards corporate reporting. If this is a big need for you, then this book goes along way to meeting your needs. If you have no need for corporate reporting, it's wasted paper.

This is an excellent book; it does exactly what it sets out to do and fully equips you to handle the most sophisticated database transactions.

---

You can purchase SQL Cookbook from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

Recommendation

As most people I know learn SQL and PHP together, if you're to the point that this book would be of benefit to you, I'd suggest also getting the PHP Cookbook. That book has done wonders on improving the quality of my code.

Re:Recommendation

If they write SQL like most people write PHP...yeesh.

In my experience, the people who generally most need SQL books like this are the report guys...You know, not really IT, just kinda work on the fringes of things with Access and Crystal Reports...Don't know much about code, but are good with the data. I can see one of these being really useful. I have the Java Cookbook (and the Php cookbook, as it happens. =P), and they're pretty handy, though they fill a niche that I usually fill with google.

Re:Recommendation

Google has failed me a few times with PHP issues, the cookbook has helped fill in the gaps there.

Problems with finding answers on the web:

1) The code for the answers to problem A and problem B don't necessarily work together

2) The code is of questionable quality. I'm six months in to teaching myself PHP (and CSS, SQL, and a few web server applications) and I can tell you that the code I wrote just two months ago was utter crap, largely because it was based on web tutorials that completely neglected good practices.

3) I have no prior experience or training with programming, which makes it hard to even know where to start looking for a solution. Books like this have helped me learn how to know what I need to search for.

Re:Recommendation

The PHP manual is the absolute must use resource.

Not only is it obviously a complete reference guide to the language, but the user comments on each function often cover a wide variety of uses that can help solve your particular problem. More importantly, if poor quality code is posted, someone will often post a cleaned up version.

Not to knock books at all. Just saying, there's a great free resource out there that is vastly superior to the hundreds of ad ridden script sites.

Re:Recommendation

Normally, I do staight coding on servers, sometimes the client. Most of my work does not involve huge amounts of DB work. So I get by on the DB, but I do not consider it a strength.

Now, I am in a job where currently, I am testing data that is being modified through a series of transforms. We test by loading the end work and taking it back to the initial work (i.e. we reverse the process). We find it easy to load the data into a Postgres DB, create views with conversion functions to take end->initial and then run an assortment of queries over the data to make certain that it is correct. I have found that I do go back to several book to make sure of my sql as well as to improve the speeds (a subquery took 20 min to run while using a except gaves a similar answer in under several seconds. BIG difference considering that we are looking at many tables with a number of tests each).

The books help.

Re:Recommendation

Most people I know who use SQL work in Java, Ruby, Python, C++, JDBC, ODBC, ASP.NET, Hibernate, etc. Please, there are so many SQL related technologies. PHP is not the be-all, end-all one. The beauty of SQL is that it's a language, platform independent way to define and manipulate relational data. It's a data-centric way to deal with data. Adding one of the related language to the mix just muddles things.

sequel?

Shit, I've been calling it squirrel all this time!

Microsofties say "sequel"

Unix MEN say S.Q.L.

Re:Microsofties say "sequel"

I believe you're correct. http://en.wikipedia.org/wiki/SQL#History [wikipedia.org]

During the 1970s, a group at IBM's San Jose research center developed a database system "System R" based upon, but not strictly faithful to, Codd's model. Structured English Query Language ("SEQUEL") was designed to manipulate and retrieve data stored in System R. The acronym SEQUEL was later condensed to SQL because the word 'SEQUEL' was held as a trademark by the Hawker-Siddeley aircraft company of the UK. Although SQL was influenced by Codd's work, Donald D. Chamberlin and Raymond F. Boyce at IBM were the authors of the SEQUEL language design.[1]. Their concepts were published to increase interest in SQL.

Oh, and as to the OP stating that SQL is difficult, try IMS.

I'll take any SQL system over an IMS or other heirarchical anyday. :P I had the unfortunate need to learn IMS after years of various SQL databases. Sure it is faster, but what a learning curve!

You sound funny

If SQL is pronounced 'ess cue ell', is MySQL pronounced 'emm why ess cue ell'?

BN vs. Amazon

You could pay $39 from BN, or $26.37 at Amazon.

This looks like a very handy reference for those of us who can read SQL statements alright, but have grown lazy with all the GUI SQL-statement builders that exist now.

The practical SQL handbook

For those of you just starting out, try the the practical sql handbook. [amazon.com] I recently glanced through edition 3. I started at edition one years ago. It still remains an awesome book.

Joe Celko

There are a few books by Joe Celko like SQL For Smarties that are in the position of honor on my bookshelf. If you're beyond "select * from emp" and want to really learn how to efficiently get things done in a relational database, Celko is your guy.

More Cooking with SQL

SELECT eggs (*) AS ingredients
FROM Refrigerator
GROUP BY NO.dozen
INSERT INTO my_fryingpan (eggs1, butter1)
UPDATE my_table SET toast = 'lightly browned'
INSERT hole INTO toast
MERGE eggs INTO toast
USING (
SELECT Eggs, Toast)
CREATE Breakfast eggy_toast
DELETE FROM my_table WHERE plate = 'N'

Re:More Cooking with SQL

SELECT eggs (*) AS ingredients
FROM Refrigerator
GROUP BY NO.dozen
INSERT INTO my_fryingpan (eggs1, butter1)
UPDATE my_table SET toast = 'lightly browned'
INSERT hole INTO toast
MERGE eggs INTO toast
USING (
SELECT Eggs, Toast)
CREATE Breakfast eggy_toast DELETE FROM my_table WHERE plate = 'N'

You fool! You didn't specify nolock in that first select statement
. . .
. . .
and I don't know if it's sadder that you wrote that SQL statement or I critiqued it

A book about SQL? Revolutionary!

SQL, you say? Never heard of it. Must be something new.

Speak more slowly, please...

One of the staples of corporate I.S. development is processing data, and increasingly these days that data lives in a relational database.

Thank you, Mr. Obvious!

There is also a MySQL Cookbook

As with the author of this review, I really like the cookbook format. I've made heavy use of the MySQL cookbook, also from O'Reilly, by Paul DuBois. It is excelent, and just about everything that Simon P. Chappell says about the SQL Cookbook applies, except of course the focus on just MySQL. I'm glad to hear of the SQL cookbook because I'll be developing for postgresql as well as MySQL in the near future. Thanks.

sql

Select * From SovietRussia Where Article AND ReadsYOU

SQL is a standard. Is it?

What I have always found funny about SQL is that, while it's very 'old' (in software terms), and mature, and widely used, there is in fact no real standard. There never was. From the article:

SQL variations ... While SQL is a standard, there seems to be some very relaxed definitions of full adherence to that standard...

Or, as Jim Starkey said: 'SQL isn't a standard but a theme'. For a book, it means list 5 different dialects. For regular developers (not database specialists) it means knowing only one dialect really well. For an application it means, running only with one database (mostly). It would be really cool the industry could get together and define a 'real' standard. Could be a subset of SQL (http://ldbc.sf.net/ [sf.net]) or a new language (http://newsql.sf.net/ [sf.net]). Things would get simpler then.

(Side note: LDBC and NewSQL are both projects I started, but interest was quite low; currently I'm working on a new database engine http://www.h2database.com/ [h2database.com] where I try to be compatible as much as possible with existing databases)

Or is there some other solution? I don't think that that O/R mapping tools will solve the problem completely, as there is always the need interactive database queries. Maybe the Microsoft extension to C# (forgot the name) could be a solution? Other ideas?

Re:SQL is a standard. Is it?

there is in fact no real standard

Yes, there's a great deal of nonconformance and extensions.

But, there is a standard, in fact, five: SQL-86, SQL-89, SQL-92, SQL:1999 and SQL:2003 (yeah, dashes replaced by colons, go figure). SQL:2003 can be purchased from ANSI or ISO, just like the C or C++ standards.

Various sites [www.tar.hu] list product conformance to the standards.

When I write SQL, I pretty rigorously stick to SQL-99, as that's likely to be supported by most vendors. If I need to deviate from that, I make sure I know how to replicate the vendor-specific code in SQL-99 (e.g, postgresql's inherits keyword -- it's useful for sub-typing, but it can be effected by using joins and views).

If the non-standard code is DML (not DDL), I'll do my best to encapsulate it in a stored procedure or a view, and let the rest of my code call the encapsulated abstraction. This is just the same layering you'd do in any programming language to wall off platform-specific code. And just as you'd typedef in C or create abstract types in C++, you create UDTs in SQL too.

Here's an example, using a useful testing date "function" that is cross-dialect, doesn't rely on any user-supplied function support, and can be incorporated into live code.

-- postgresql
CREATE DOMAIN datetime_type timestamp null;
create view system_datetime as select 1 as id, now() as date_now ;

-- MS SQL server
create type datetime_type from datetime null;
create view system_datetime as select 1 as id, getdate() as date_now ;


-- code below is SQL dialect independent
-- works on postgresql or MS SQL server

-- code to use actual current date or fake date for testing purposes
-- all DML that wants the current system timestamp should instead join on (or subselect) the view date_now
-- this view always returns a single row

create table test_date ( id int, test_date datetime_type ) ;
insert test_date values ( 1, null ) ;

create view date_now as
select
coalesce(
( select test_date from test_date where id = 1) ,
( select date_now from system_datetime where id = 1)
) as date_now ;

-- note: for Sybase, replace coalesce with isnull

-- see what invoices were due as of January 1:
update test_date set test_date = '1/1/2006' ;

select * from invoices a, date_now b
where a.issue_date <= b.date_now
and ( a.paid_date > b.date_now or a.paid_date is null )

-- look at real invoices due as of now
-- Query is the same, we just null out the fake date:
update test_date set test_date = null ;

select * from invoices a, date_now b
where a.issue_date <= b.date_now
and ( a.paid_date > b.date_now or a.paid_date is null )

(And yes, you can hire me.)

Sample chapter

Chapter 11: Searching [oreilly.com]
40 pages, 500k PDF

Yawn...

Great - yet another book that teaches me the "ins-and-outs" of the "Northwind" database. Seriously, when are publishers and authors going to come out with more original content? For instance - content for those of us that AREN'T designing HR or order entry apps?

Ah well, it could be worse - it could be teaching me how to build another class registration system....

What I could use...

is a book full of sample queries.

Half the time I am using PHP for something SQL could do in a couple simple commands.

SQL Cookbook Lowest Price

You can track the lowest price here for "SQL Cookbook" here:

http://www.alienegg.com/lowest-price-finder.php?ur l=http%3A%2F%2Fwww.amazon.com%2Fgp%2Fproduct%2F059 6009763%2Fsr%3D1-1%2Fqid%3D1147293625%2Fref%3Dsr_1 _1%2F002-4415993-5683262%3F%255Fencoding%3DUTF8 [alienegg.com]

five stars

(Average of 1 Customer Reviews)

Not for beginners?!? Doubtful

I am not sure how anyone can resolve the following found in the review - emphasis mine.

The book is not for beginners and makes no efforts to teach any SQL. It concentrates purely on building on the base level of SQL knowledge that most programmers have. If you know the basics: Create, Read, Update and Delete (an unfortunate, yet memorable acronym) but rarely go beyond that, this book is for you. I know that I fall into this target market.

Recipe one in chapter one, titled "Retrieving all Rows and Columns from a Table" has the problem statement "You have a table and want to see all of the data in it." Nice and clear. Then comes the solution. Naturally, for this problem statement we end up with a SELECT that looks like this:

select * from emp

How can a book not be for beginners when the first recipe teaches the most basic SQL command possible? I have this book and it is a very good book, but like most technical books it kills a great deal of trees needlessly to pad its count. You can probably rip more than 100 pages out of the book that is mindless beginner crap and self-flogging and actually have a very good technical reference for mid-level SQL people.

set theory

I spend a lot of work hours reading/debugging/re-writing other peoples MSSQL stored procs. While it seems the people before me didn't understand the idea of a set-based language at all (CURSORS! CURSORS! CURSORS!) I understand the concept but have little experience implementing it. Can anyone suggest a SQL reference that puts emphasis on teaching how to implement set-based logic in stored procs, rather than just procedural batches?

Time to put SQL out to pasture

SQL is growing long in the tooth. It is time to replace it with something better that learns from lessons of the past. One proposal is Tutorial D, by Chris Date. I have also proposed "TQL" (or SMEQL due to a name comflict with another product) as a draft SQL replacement. Unlike Tutorial D, SMEQL uses a prefix notation for the main relational operaters. This makes it easier to extend by DBA's. If you don't like the out-of-the-box set of relational operators, you can define your own (using the existing ones). I have even created a wannabe book cover [geocities.com] for SMEQL.

ebooks / standards

Are there any good e-books one could refer to for SQL? Is there a freely available standards document which describe how `base` SQL "should" be, like say the ANSI standards for C?

Casing and layout of SQL-examples.

From the pdf of _Chapter 11_ [oreilly.com]

select a.ename,
              (select count(*)
                  from emp b
                where b.ename <= a.ename) as rn
    from emp a

I would layout that like

SELECT a.ename,
              (SELECT COUNT(*)
                  FROM emp AS b
                WHERE b.ename <= a.ename) AS rn
    FROM emp AS a

or like

select a.ename,
              (select count(*)
                  from emp as b
                where b.ename <= a.ename) as rn
    from emp as a

SQL for Smarties

SQL for smarties is the best advanced SQL book I've seen. Highly recommended for developers, and should be on the bookshelf of any DBA.

Yes, but does it work in Europe?

I'd buy this book in an instant if it could give me a good (efficient) solution for this query: return the set of most recent sales grouped by customer. [Stands back and smirks while flocks of geeks bang their heads against relational algebra]

Re:Mispronunciation

SQL started out being called SEQUEL (and pronounced as such) until it was changed to SQL due to trademark issues. IMHO, the historical pronunciation is a valid precedent. See the History section of the SQL Wikipedia entry.

Re:Mispronunciation

Chris Date has stated in many of his books on RDMS theory and practice, several of which were published before many Slashdotters were born, that SQL is pronounced 'sequel'. Good enough for me.