Slashdot Mirror

Its pretty easy in Microsoft land, for instance: https://www.sqlservercentral.c... and I have done similar things in bash to restore Oracle and Sybase DBs many years ago. Of course you have to have transaction logs to replay transaction logs and writing transactions logs is optional in MySQL and even if they are written, they are by default placed in the same data directory as the database.

And a foreign key is just a copy of a primary key in another table, plus constraints. Learn that one :-)

If you want to give your employer a bit of value in your SQL experiments, show him an Iron Speed demo. Ain't free, but it's cheap, and you can pump out a lot of web-based reports for them quickly (Bosses love reports, and they love quickly). You'll also learn your way around IIS (yes all you out there, Apache rocks, I know, I've heard it, I've supported it. Give the guy a break, ok?) which means you can learn about Exchange's outlook web access at the same time, if they're running Exchange - and most businesses will, for a while longer anyway.

Also, if you're on an intranet (not talking about DMZ here) you definitely want to specify Active Directory security integration, and don't muck with the default collating order unless you really know you want it.

And don't use auto-shrink. At all.

I've found SQL Server Central to be useful sometimes http://www.sqlservercentral.com/ -- go there and start reading.

That information should have been encrypted within the database. Why, just the other day SQLServerCentral.com posted a tutorial on creating a transparent database encryption layer. When managing critical information like SSN's or embassy cables, clear text is just asking for a compromise.

Oh, and I am not saying Windows is anything at all good to have in anyone's life. In fact, the insecure nature of laptops and malware demands that security be increased closer to the sensitive data.

Seth

Are we talking parent-child hierarchy tables? If so, Oracle's had statements to take care of that for a long time, since 1998 or so. Perhaps not ANSI standard, but they get the job done.

No, I'm talking about Common Table Expressions (okay, so I was slightly wrong about implementation of CTEs -- apparently other products have implemented the standard, but DB2 and SQL Server 2005 are the only "Big Boy" engines with them). CTEs aren't so much about implementing a hierarchy as they are about doing recursive actions quickly and efficiently. Walking a parent-child hierarchy is just an example of a recursive problem that's easily solved with a CTE, but CTEs don't dictate how you should store your relationship information.

For what it's worth, it's possible to write recursive algorithms in just about any SQL implementation (convert your recursion to iteration, and it's not so bad), but the win with using CTEs is that it's still a set operation. Doing the loop yourself means you're losing SQL's set-based power. I did a little comparison on a naive parent-child implementation, doing two things: return the path to parent from a given node, and return the subtree of a given node. I implemented each algorithm in SQL 2000's T-SQL without CTEs and in SQL 2005 with CTEs. The CTE implementation was approximately 10 times faster than the by-hand iteration solution.

I haven't used these in real life, but they seem like they could be quite useful in your rule-based situation:

Recursive queries in SQL Server 2005

1. Code Project
2. SQL Server Central
3. .NET Weblogs, SQL Junkies
4. ASP.NET forums
5. 4 Guys from Rolla
6. ASP Alliance mailing lists
7. CodeGuru discussion forums
8. TopXML discussion forums - this is mostly about Microsoft XML technologies
9. .NET Junkies
10. SQL Team .

Actually, quite a few sites are making money, but only those that manage themselves well. In other words, as a real business.

I used to write for a site that paid very well. However, they "restructured" their payments in the middle of my deal becuase they were not making money. As a result, I started my own site with some friends. We make money at www.sqlservercentral.com, but we can't pay anywhere near what some other sites pay. Of course, some of those are still "restructuring" because they are not making money.

I think many .coms would still be doing well if they had managed their business like a business and not thrown money away.