On 30 May 2017 at 13:02, Steve Ebersole <steve(a)hibernate.org> wrote:
For whatever reason JPA and a few of the databases do not categorize
coalesce and nullif as functions - hence the "not technically a function"
part.
However in Hibernate I have defined them as functions for the sake of users
being able to plug in custom function templates.
Thanks, it's clear now.
Sanne
On Tue, May 30, 2017 at 5:14 AM Sanne Grinovero <sanne(a)hibernate.org> wrote:
>
> Hi Steve,
> just a curiosity; for `coalesce` and `nullif` you stated "not
> technically a function, but supported as such to allow overriding".
>
> What does it mean?
>
> Thanks!
> Sanne
>
> On 29 May 2017 at 22:29, Steve Ebersole <steve(a)hibernate.org> wrote:
> > Hibernate has always defined a set of functions that should always be
> > available on every Dialect/database. JPA formalized some of these, but
> > Hibernate still had a superset. So I wanted to formalize the complete
> > set
> > of supported functions. Here is the formalized list of what Hibernate
> > has
> > always considered the "supported list":
> >
> > - those defined by JPA
> > - abs
> > - avg
> > - concat
> > - count
> > - current_date
> > - current_time
> > - current_timestamp
> > - length
> > - locate
> > - lower
> > - max
> > - min
> > - mod
> > - sqrt
> > - substring
> > - sum
> > - trim
> > - upper
> > - Hibernate extensions
> > - bit_length
> > - coalesce - not technically a function, but supported as such to
> > allow overriding
> > - cast
> > - day - generally defined as `extract(day from ?1)`
> > - extract
> > - hour - generally defined as `extract(hour from ?1)`
> > - minute - generally defined as `extract(minute from ?1)`
> > - month - generally defined as `extract(month from ?1)`
> > - nullif - not technically a function, but supported as such to
> > allow
> > overriding
> > - second - generally defined as `extract(second from ?1)`
> > - str - generally defined as `cast(?1 as CHAR )`
> > - year - generally defined as `extract(year from ?1)`
> >
> >
> > Additions/subtractions anyone would like to discuss?
> >
> > One question I has was in regards to str being defined as `cast(?1 as
> > CHAR
> > )` by default - specifically using CHAR instead of VARCHAR. Some
> > databases
> > apply padding for the size of the datatype when casting a numeric to a
> > CHAR
> > which is not an unreasonable thing to do.
> > _______________________________________________
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> > hibernate-dev(a)lists.jboss.org
> >
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