Ivan, Thank you, I got your concern now. As it is mostly regarding the terminology, I am absolutely fine with changing the name to whatever fits the approach best. Dynamic or evolving schema sounds great. I will make corresponding changes to the IEP once we settle on the name.
пн, 7 сент. 2020 г. в 11:33, Ivan Pavlukhin <vololo...@gmail.com>: > Hi Val, > > Thank you for your answer! > > My understanding is a little bit different. Yes, schema evolution > definitely should be possible. But I see a main difference in "how > schema is updated". I treat a common SQL approach schema-first. Schema > and data manipulation operations are clearly separated and it enables > interesting capabilities, e.g. preventing untended schema changes by > mistaken data operations, restricting user permissions to change > schema. > > > Schema-first means that schema exists in advance and all the stored data > is compliant with it - that's exactly what is proposed. > > A schema-last approach mentioned in [1] also assumes that schema > exists, but it is inferred from data. Is not it more similar to the > proposing approach? > > And I would like to say, that my main concern so far is mostly about > terminology. And I suppose if it confuses me then others might be > confused as well. My feeling is closer to "dynamic or liquid or may be > evolving schema". > > [1] > https://people.cs.umass.edu/~yanlei/courses/CS691LL-f06/papers/SH05.pdf > > 2020-09-07 0:47 GMT+03:00, Valentin Kulichenko < > valentin.kuliche...@gmail.com>: > > Hi Ivan, > > > > I don't see an issue with that. Schema-first means that schema exists in > > advance and all the stored data is compliant with it - that's exactly > what > > is proposed. There are no restrictions prohibiting changes to the schema. > > > > -Val > > > > On Sat, Sep 5, 2020 at 9:52 PM Ivan Pavlukhin <vololo...@gmail.com> > wrote: > > > >> Alexey, > >> > >> I am a little bit confused with terminology. My understanding conforms > >> to a survey [1] (see part X Semi Structured Data). Can we really treat > >> a "dynamic schema" approach as a kind of "schema-first"? > >> > >> [1] > >> https://people.cs.umass.edu/~yanlei/courses/CS691LL-f06/papers/SH05.pdf > >> > >> 2020-09-02 1:53 GMT+03:00, Denis Magda <dma...@apache.org>: > >> >> > >> >> However, could you please elaborate on the relation between Ignite > and > >> >> ORM? > >> >> Is there a use case for Hibernate running on top of Ignite (I haven't > >> >> seen > >> >> one so far)? If so, what is missing exactly on the Ignite side to > >> support > >> >> this? In my understanding, all you need is SQL API which we already > >> have. > >> >> Am I missing something? > >> > > >> > > >> > Good point, yes, if all the ORM integrations use Ignite SQL APIs > >> > internally, then they can easily translate an Entity object into an > >> > INSERT/UPDATE statement that lists all the object's fields. Luckily, > >> > our > >> > Spring Data integration is already based on the Ignite SQL APIs and > >> > needs > >> > to be improved once the schema-first approach is supported. That would > >> > solve a ton of usability issues. > >> > > >> > I would revise the Hibernate integration as well during the Ignite 3.0 > >> dev > >> > phase. Can't say if it's used a lot but Spring Data is getting > traction > >> for > >> > sure. > >> > > >> > @Michael Pollind, I'll loop you in as long as you've started working > on > >> the > >> > Ignite support for Micornaut Data > >> > <https://micronaut-projects.github.io/micronaut-data/latest/guide/> > and > >> > came across some challenges. Just watch this discussion. That's what > is > >> > coming in Ignite 3.0. > >> > > >> > > >> > - > >> > Denis > >> > > >> > > >> > On Mon, Aug 31, 2020 at 5:11 PM Valentin Kulichenko < > >> > valentin.kuliche...@gmail.com> wrote: > >> > > >> >> Hi Denis, > >> >> > >> >> Generally speaking, I believe that the schema-first approach natively > >> >> addresses the issue if duplicate fields in key and value objects, > >> because > >> >> schema will be created for a cache, not for an object, as it happens > >> now. > >> >> Basically, the schema will define whether there is a primary key or > >> >> not, > >> >> and which fields are included in case there is one. Any API that we > >> would > >> >> have must be compliant with this, so it becomes fairly easy to work > >> >> with > >> >> data as with a set of records, rather than key-value pairs. > >> >> > >> >> However, could you please elaborate on the relation between Ignite > and > >> >> ORM? > >> >> Is there a use case for Hibernate running on top of Ignite (I haven't > >> >> seen > >> >> one so far)? If so, what is missing exactly on the Ignite side to > >> support > >> >> this? In my understanding, all you need is SQL API which we already > >> have. > >> >> Am I missing something? > >> >> > >> >> -Val > >> >> > >> >> On Mon, Aug 31, 2020 at 2:08 PM Denis Magda <dma...@apache.org> > wrote: > >> >> > >> >> > Val, > >> >> > > >> >> > I would propose adding another point to the motivations list which > >> >> > is > >> >> > related to the ORM frameworks such as Spring Data, Hibernate, > >> Micronaut > >> >> and > >> >> > many others. > >> >> > > >> >> > Presently, the storage engine requires to distinguish key objects > >> >> > from > >> >> the > >> >> > value ones that complicate the usage of Ignite with those ORM > >> >> > frameworks > >> >> > (especially if a key object comprises several fields). More on this > >> can > >> >> be > >> >> > found here: > >> >> > > >> >> > > >> >> > >> > http://apache-ignite-developers.2346864.n4.nabble.com/DISCUSSION-Key-and-Value-fields-with-same-name-and-SQL-DML-td47557.html > >> >> > > >> >> > It will be nice if the new schema-first approach allows us to work > >> with > >> >> > a > >> >> > single entity object when it comes to the ORMs. With no need to > >> >> > split > >> >> > the > >> >> > entity into a key and value. Just want to be sure that the Ignite > >> >> > 3.0 > >> >> > has > >> >> > all the essential public APIs that would support the single-entity > >> >> > based > >> >> > approach. > >> >> > > >> >> > What do you think? > >> >> > > >> >> > - > >> >> > Denis > >> >> > > >> >> > > >> >> > On Fri, Aug 28, 2020 at 3:50 PM Valentin Kulichenko < > >> >> > valentin.kuliche...@gmail.com> wrote: > >> >> > > >> >> > > Igniters, > >> >> > > > >> >> > > One of the big changes proposed for Ignite 3.0 is the so-called > >> >> > > "schema-first approach". To add more clarity, I've started > writing > >> >> > > the > >> >> > IEP > >> >> > > for this change: > >> >> > > > >> >> > > > >> >> > > >> >> > >> > https://cwiki.apache.org/confluence/display/IGNITE/IEP-54%3A+Schema-first+Approach > >> >> > > > >> >> > > Please take a look and let me know if there are any immediate > >> >> > > thoughts, > >> >> > > suggestions, or objections. > >> >> > > > >> >> > > -Val > >> >> > > > >> >> > > >> >> > >> > > >> > >> > >> -- > >> > >> Best regards, > >> Ivan Pavlukhin > >> > > > > > -- > > Best regards, > Ivan Pavlukhin >
