Reply to: Job specs asking for specific database experience

[Peoplesoft bloke]

.......
Worst I've seen was a migration script which was written by a C# programmer. It was taking over 12 hours to run.
Took me less than 15 minutes to rewrite it so it ran in a couple of minutes... they'd wasted weeks on it

Maybe he was following advice from an old boss of mine - "never make it run as fast as you can first time, or you've got nowhere to go when the users complain about performance"

[MrMark]

When I was looking for a role a few months back, I often got no further than the initial phone call to the agency because the role asked for experience with Oracle, sometimes PL/SQL.

End of the day, if the recruiter has specified Oracle experience (as well as Java) then that's what the agency will try and provide. Remember that the agent (if s/he advertised it well enough) may well have had 20-30 applications, and needs to whittle down the list to one or two finalists. As mentioned above, it's all very well having a general of set theory, and how to use sub-queries etc but there's a lot of ways of optimising your code that need experience of Oracle. Not to mention the deprecated non-standard stuff that may still turn up in existing code.
If it is important to you to gain Oracle experience, maybe you should seek out a migration role somewhere (possibly a lot less than you're on now) ? Or take one of those Indian courses (I'm not sure that would satisfy a recruitor in a case like this though)

[Spacecadet]

PL/SQL is good...but I would never put my business logic in the database. I have heard of some groups which have done it. So when you change DB technology, you end up forking out mega $$$ to rewrite it all.

They

Always think of repeatable business
Business logic in database means extra work at DB upgrade time
Kerching

[expat]

Right, I've been a java developer for years now, and have fairly decent experience with most of the open source databases (MySQL, Postgres etc) and also MS SQLServer.

When I was looking for a role a few months back, I often got no further than the initial phone call to the agency because the role asked for experience with Oracle, sometimes PL/SQL.

Now today I finally got to have a play with my colleagues PL/SQL editor. I might be missing something, but Oracle is just a database right? My own SQL may not be super advanced, but I was able to get all the queries that I wanted without any problems at all. As far as I can see, once you've seen one data query tool, you've seen them all. We're not talking major DBA work here, just the basic CRUD stuff common to most development roles.

What's the big secret? Am I really not qualified to take on a development role where the database is Oracle, or should I be persuading the agent that it's not an issue?

The specific point about PL/SQL is that it is procedural, which SQL is not. Yes, one of the things that you can do in a PL/SQL environment is run ordinary SQL queries with no procedural processing, but that's not really PL/SQL. From a job point of view, if it really requires PL/SQL then it probably makes use of the procedural aspects.

Or the agent has no clue.

[lilelvis2000]

Unfortunately many programmers think that SQL is a "piece of piss" and don't give it the time it requires.
Worst has to be the use of cursors when there is absolutely no need fo it.

I've lost count of how many times I've had to fix programmers attempts at SQL because they've made basic errors in their approach to the situation.

Worst I've seen was a migration script which was written by a C# programmer. It was taking over 12 hours to run.
Took me less than 15 minutes to rewrite it so it ran in a couple of minutes... they'd wasted weeks on it

Worst I saw was someone who was dynamically creating a insert statement to insert a row from a file which the application had read in. The files contained hundreds of thousands of lines. I changed it to a parameterised pre-compiled command (using ADO) and kept it in a singleton. Times went from 3+hrs to ~1min, Records per second went from 30 to ~35,000.


PL/SQL is good...but I would never put my business logic in the database. I have heard of some groups which have done it. So when you change DB technology, you end up forking out mega $$$ to rewrite it all.

[DimPrawn]

Unfortunately many programmers think that SQL is a "piece of piss" and don't give it the time it requires.
Worst has to be the use of cursors when there is absolutely no need fo it.

I've lost count of how many times I've had to fix programmers attempts at SQL because they've made basic errors in their approach to the situation.

Worst I've seen was a migration script which was written by a C# programmer. It was taking over 12 hours to run.
Took me less than 15 minutes to rewrite it so it ran in a couple of minutes... they'd wasted weeks on it

What he said.

Being able to manipulate large amounts of data in a complex schema requires deep insight into set theory rather than procedural code, subtle differences between joins, subselects, correlated subqueries, and unions, as well as locks, optimiser hints, etc.

[TheBigYinJames]

Worst I've seen was a migration script which was written by a C# programmer. It was taking over 12 hours to run.
Took me less than 15 minutes to rewrite it so it ran in a couple of minutes... they'd wasted weeks on it

claimed loads of overtime for

[Spacecadet]

Though any decent Java/C# developer should be able to implement anything in SQL, and to be able to do so well.

Unfortunately many programmers think that SQL is a "piece of piss" and don't give it the time it requires.
Worst has to be the use of cursors when there is absolutely no need fo it.

I've lost count of how many times I've had to fix programmers attempts at SQL because they've made basic errors in their approach to the situation.

Worst I've seen was a migration script which was written by a C# programmer. It was taking over 12 hours to run.
Took me less than 15 minutes to rewrite it so it ran in a couple of minutes... they'd wasted weeks on it

[swamp]

PL/SQL is no biggie. It's basically TSQL (Sybase, SQL Server) but a bit better.

Problem is it was designed to be an almost fully-fledged programming language, which as a Java dev makes me cringe. The orange O'reilly book suggests you put your business logic in PL/SQL... Good luck unit testing that!

Oracle itself is just a database, and as a Java developer you shouldn't be expected to know too much about it's architecture. Though any decent Java/C# developer should be able to implement anything in SQL, and to be able to do so well.

[Gros]

Thanks all, some really interesting responses there.

I think it's safe to say I can put on my CV that I have at least used oracle, but at least I understand now why it's fair enough if I lose out to someone with some proper PL/SQL experience.

Cheers.

[DimPrawn]

I always like the gotcha's in Oracle. For instance,

How would you perform string manipulation on a long data type.

I'd upgrade it to SQL Server 2008 and then take the rest of the six months contract off, as you don't need to spend time trying to work round a bitch of a product.

[Weltchy]

See above, Re: do it in assembler.

[VectraMan]

I always like the gotcha's in Oracle. For instance,

How would you perform string manipulation on a long data type.

See above, Re: do it in assembler.

[Weltchy]

I always like the gotcha's in Oracle. For instance,

How would you perform string manipulation on a long data type.

[VectraMan]

You just need "SELECT * FROM table"

It's all I've ever needed. Sort the data with assembler, and it's fast too.