ADBA feedback

[Lukas Eder]

I don't fully see the maintenance nightmare aspect here. In many years of
working with JDBC, I don't recall having preferred (Stringly typed) name
based access over index based access, neither in infrastructure code like
some in-house JDBC libraries or jOOQ, nor in actual business logic.
Especially infrastructure code works better with index based access,
precisely because of the non-ambiguity.

Another example:

SELECT a, b + c, COUNT(*) OVER()
FROM x

What is the column name of the second and third columns? In some databases,
it might be "b+c" and "count". In others, it might be "B+C" and
"COUNT(*)OVER()". Then there's the question about case sensitivity of
column names. Will they be projected in upper case or lower case or mixed
case? Can we rely on that? How to write database agnostic code that works
the same on all databases?

You might be tempted to think that we could alias the columns with quoted
identifiers, to be sure:

SELECT a, b + c AS "b", COUNT(*) OVER() AS "c"
FROM x

But the caveat is:

1) Some databases require quoted identifiers to be in [brackets], or in
`backticks`
2) Some databases use quotes only to support special characters, not to
make the identifiers case sensitive, so there still isn't any guarantee
about the casing

Of course, a driver might choose to make the get(String) method case
insensitive to work around the above, but as you can see, the only really
reliable way to access columns is by index, and I do think they should be
made first class citizens in the API (just like in JDBC) for the many
reasons I've mentioned in this discussion.

2018-04-27 17:34 GMT+02:00 Douglas Surber <douglas.surber at oracle.com>:

> I definitely see your point.
>
> Index based access (and SELECT *) are maintenance nightmares. If we must
> have index based access how about something like this:
>
>   /**
>    * Return the value of the nth occurrence of an out parameter or select
> value identified by id.
>    */
>   public <T> T get(String id, int n, Class<T> type);
>
> Just a thought.
>
> Douglas
>