About sort
ORDER BY clause (JPQL / Criteria API)
Explains how to use the ORDER BY clause in a JPA/JPQL query.... Country objects ordered by currency as the primary sort key and by name as the secondary sort key: SELECT c . currency , c . name FROM Country c ...
How the sort order (in queries) works for non english letters?
We are considering using ObjectDB in project where target audience are czech speaking people (we are Czech company). How the sort order works for international (for us 'czech') letters? Does the ordering respects the national requirements? Thank you for clarification ... ... are czech speaking people (we are Czech company). How the sort order works for international (for us 'czech') letters? Does the ... if possible. Normalizing the strings only during sort is also possible, but it is less efficient, of course. See also ...
Sorting problem
Hi, I was rewriting our DAO to support pagging in large dataset and I think I have found a problem with sorting. I send you a test case - sorry for using the same project as previous, but it was faster to write this test case. As usual, you can load data with DataLoader and then check problem with QueryData. There is a simple query with "order by" sentence: ... expression is the same for all the result objects - the sort didn't have any effect. ObjectDB Support ...
Sort of very large objects - out of memory
The attached test is failing with an out of memory exception when running with -Xmx512m It performs the following actions: 1) Create 5 persist threads which create and persist a large object in a loop 100 times each 2) Create 5 get threads which read 100 objects each in a loop based on object creation time and priority The message size should be around 1mb so I think there should be around 11mb of "live" data in play at any time. The objectdb cache settings are low in the config - database section is below for reference. ... , createTime could even be faster if both sort keys were either ascending or descending, since then a range query could ...
Cannot sort descending, when ordering by caluculated float in a method
Hi, I have found an issue in ordering by a method. I have two entities : Invoice and InvoiceItem. public class InvoiceItem{ .. private float price; private float amount; .. } public class Invoice{ #1 2011-06-23 19:43 Hi, I have found an issue in ordering by a method. I have two entities : Invoice and InvoiceItem. public ...
Query perfromance problem
Hi, I was playing with paging and sorting recently and after trying few different aproaches got some strange behavior from ODB. First of all, I will show you results from page rendering times, but trust me - when debugging application, getting data from ODB takes a long time in one case. Anyway, one of my methods in DAO looks like this: ... else { logger. debug ( "Sort column: {}, ascending {}" , sortColumn, isAscending ) ; ... order in given way. Now, when running this query with sort column set to 'id', it takes about 9-11 seconds to render webpage: ...
Index Definition
Describes how to define indexes in JPA entity classes and explains how indexes are used in JPQL queries.... it determines which field is used as the BTree's primary sort key and which field is used as a secondary sort key. If x is specified first, the BTree is ordered by x values, so ...
Listing large number of complicated objects with paging.
Hi, For last few hours I was working on a problem with bad performance and memory problems with such a simple query: select prod from Product prod order by prod.id ASC Right now I have 55541 'Product' (attached to this post) entities in database and I'm trying to speed listing them with paging. The problem is, that running code that looks like this: ... <orderPlan plan="sort(fetch(index(-279[all])))" eval="9.3782" var="1" prm="0" reg="0" ... <orderPlan plan="sort(index(-279[all]))" eval="8.0771" var="1" prm="0" reg="0" ...
ORDER BY problem, when String starts with language specific character
Dear all, I have a problem with ORDER BY clause. I have a simple query: select u from User u order by u.name When the name starts with "normal/english" character, records are ordered correctly. But when it starts with language specific character like 'Č', these records are placed after records with normal charaters. So records with 'Č' are after 'Z', but this is not correct, because 'Č' is between 'C' and 'D'. ... and 'D'. Is there any way, how to sort the records correctly? Thank you Michael ... query ORDER BY clause. However, if you have to sort a large result list - it might be more efficient to add a persistent ...
Threaded Test - Failed to commit transaction: Unexpected internal exception
Hi I'm trying to create a simple producer-consumer queue scenario but am getting the followin exception: ... the test too early. I cannot explain the effect of the sort either. Please try running the test after adding the missing ... The problem is indeed in running a query with sort: SELECT p FROM IdPoint p ORDER BY p . priority ...
