Re: ResultSet.getClob() causing problems when used with JPA's @Lob

On 02/07/2011 10:38 PM, Radosław Smogura wrote:
> PostgreSQL doesn't have field type CLOB, nor BLOB.

I know that.

> If eveny it would be possible for driver to read CLOB from varchar, driver
> will be unable to set proper value when calling UPDATE or INSTERT. It is due
> to internal way how PSQL deals with those values.

Isn't the whole concept of CLOB just a bi-product of old proprietary
database-design where some RDBMS'es are unable to store arbitrary long
varchars? What properties do CLOBs have that varchars don't, except
being large? I don't understand why CLOBs can't be treated like text in
the PG-driver as PG handles large Strings just fine in
varchar/text-columns. If a DBA has for some reason defined a scale, say
VARCHAR(10), on a column and tries to store a CLOB in it, well - his
problem; He should get an Exception from PG.

> I know drivers supports custom casting, but casting from varchar to clob is
> implicite prohibted in JDBC. If you look at B-6 table x indicates possible
> casting. There is no x, nor X on varchar cross clob

Does it not make sense to you to be able to cast a *character large
object* to a *variable length character*-type and visa versa?

If the only argument is spec-complience I'm not getting it...

--
Andreas Joseph Krogh <andreak@officenet.no>
Senior Software Developer / CTO
Public key: http://home.officenet.no/~andreak/public_key.asc
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