Re: Patch for jdbc escaped functions

On Fri, 3 Dec 2004, Xavier Poinsard wrote:

> Here is the (final ?) patch adding escaped functions support.
> - soundex and difference (based on phonetics and I saw nothing like that
> in PostgreSql)

contrib/fuzzystrmatch has something along these lines.  We can't assume 
that's installed naturally and dynamically checking for it seems 
excessive, but perhaps we could put in the mapping if someone wants to use 
it, but just not report it in the DatabaseMetaData function?

> - timestampadd and timestampdiff

Yes, it is unclear what SQL_TSI_* really are.

> Note that the implementations for some functions may cause problem if an
> argument is a prepared statement argument since arguments may be
> duplicated and the order changed, but I don't know if this should be
> implemented for compliance.

This is a serious problem.  Duplicating the argument and erroring out is 
bad, and switching argument order and giving incorrect results is worse.  
How many functions does this affect.  Remapping could be done, but it 
seems like a lot of work.

Another issue is that this doesn't compile with a 1.2 or 1.3 JDK because 
of the code in AbstractJdbc2Statement.escapeFunction that calls 
Exception.getCause which is a 1.4 addition.

One other minor thing I noticed is that 7.2 servers do not have the 
current_database function.  This is a very minor thing, but I'm not sure 
what the best way to work around it is because right now the regression 
test suite does pass against a 7.2 server and I'd like to keep it that 
way.

Kris Jurka