About index

forum_thread

@Unique added afterward is not taken into account

Hello, ... Unique is implemented as an index, and adding an index on existing data requires rebuilding the database by using the Doctor ...

 
forum_thread

Performance question

Hello, suppose you have an entity that holds a reference to another entity which in turn contains e.g. a date field you want to query for. Is there an improvement in performance if I create a "mirror" date field in the original entity, removing the need to traverse through the referenced other entity? So, querying for "all objects with object.otherobject.date > 1.1.1980" is slower than "all objects with object.date > 1.1.1980"? Or doesn't this matter, using proper indexing? Thanks, Benjamin #1 2011-10-20 19:01 Hello, suppose you have an entity that holds a reference to another entity which in turn contains e.g. a ...

 
api-jdo

Index.table

Table for the index.(Annotation Element of javax.jdo.annotations.Index)

 
release

2.2.3

... Improved cleanup and reusing space after index deletion. Changed default configuration (enabled recovery, ... Fixed a query execution bug when index with null keys is used. Fixed a bug in tracking field ...

 
forum_thread

Performance with large databases

When populating a large database (10s of GBs) performance drops suddenly at a certain time whenever I run the populating application.  Is there typically a database size when indexes can no longer be held fully in memory or some such issue?  The method calls that suddenly start to take the most time are those that retrieve data from the store. #1 2013-06-03 00:58 When populating a large database (10s of GBs) performance drops suddenly at a certain time whenever I run the pop ...

 
page

What is new in ObjectDB 2.0?

... IDs (primary key) and sequences. Support of unlimited index keys size. SQL like queries ("select from ... where ..."). Real ...

 
issue

Cannot insert more than about 2^20 objects

Hi I have a DB with 4 entities and a total of 4 index. Once I reach 1048565 total objects in the whole DB, i am unable to insert more object, although i get NO error message nor exceptions. Doctor said Db is fine (see below) I notice that 1048565 objects + 4 entities + 4 ID indexes + 4 other indexes = 1048576 = 2^20 . Is this a coincidence? ... Hi I have a DB with 4 entities and a total of 4 index. Once I reach 1048565 total objects in the whole DB, i am ...

 
forum_thread

Persist error @ManyToMany how to define correct entities relationships

I have Product entities containing a list of Category enties. Each product can have multiple Category but all sue the same limited set of Category entities. There is not changes made to Category from Product. The category ID is taken from the webservice Object ID (unique too). ... are created but category webservice ID are used as index (and they may already exist in objectdb). I will try with merge, this is ...   New try with @Genreated index and @Unique category ID, 1 category entity is created in the table on 2, ...

 
forum_thread

@Unique member combination not working

Why does the below code not enforce unique restrictions?   Person.java ... Unique to an existing database is like adding an index (since  Unique is implemented as an index), and therefore requires index rebuilding  (currently using the ...

 
release

2.2.2

... Improved cleanup and reusing space after index deletion. Changed default configuration (enabled recovery, ... Fixed a query execution bug when index with null keys is used. Fixed a bug in tracking field ...