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Unexpected COUNT Results

with size 1380. This is expected result If we add COUNT operator: b. SELECT COUNT($1.id) FROM Pa3DataKey ... .dataItems.get('Sender') != 'PHY' and $1.dataItems.get('Receiver') != 'PHY' e.g: c. SELECT COUNT($1.id) FROM

getting "Unexpected total page count" error when diagnosis mu db by ObjectDB doctor.

When am diagnosis my db it gave following report Global Value Errors ------------------- [1] Unexpected total page count: 512 (expected 449). On repair the db some of query are not working. can you please tell me what does the above error mean and how can i resolve this? Thanks Manoj Manoj Kumar

Processing thread count for 8-core server

In reference to the information here: https://www.objectdb.com/java/jpa/setting/database#The_processing_element_ We are working with an 8-core processor. The recommended thread count is "more than the number of cores but not too many." What would be an appropriate number of threads


Method javax.persistence.criteria.CriteriaBuilder Expression<Long> count( Expression<?> x ) Create an aggregate expression applying the count operation. Parameters: x - expression representing input value to count operation Returns: count expression Since: JPA 2.0

GROUP BY and HAVING clauses

calculations (count, sum, avg, max, min) that are carried out on all the objects (or the object tuples) in ... functions of SQL: COUNT - returns a long value representing the number of elements. SUM - returns the sum ... values (numeric, strings, dates). The following query counts for every letter the number of countries

Negative snapshot user count

I finally hit an instance of the "Negative snapshot user count" exception 1) [ObjectDB 2.3.2_01 ... .o.InternalException: Negative snapshot user count com.objectdb.o.InternalException: Negative snapshot user count at com.objectdb.o.SNP.z(SNP.java:292) at com.objectdb.o.SFL.Z(SFL.java:765) at com

Negative snapshot user count exception

.objectdb.com/database/issue/new com.objectdb.o.InternalException: Negative snapshot user count com.objectdb.o.InternalException: Negative snapshot user count at com.objectdb.o.SNP.D(SNP ... that case, the "Negative snapshot user count" and the "mismatch client-server protocol" errors

ClassCastException thrown when running count query

Hello! Attached you find a full stacktrace. The query was: SELECT COUNT(t) FROM Position t WHERE ((t.unit = :unit165w7ppbtu9ao AND t.receiveTime >= :receiveTimes232ne30kd42) AND (t.latitude ... a null pointer exception. Now back to the count query: SELECT COUNT(t) FROM Position t WHERE ((t

Running JPA Queries

: TypedQuery<Long> query = em.createQuery( "SELECT COUNT(c) FROM Country c", Long.class); long ... of a single object is easy and the code is simple: Query query = em.createQuery("SELECT COUNT(c) FROM Country c"); long countryCount = (Long)query.getSingleResult(); An aggregate COUNT query

CRUD Database Operations with JPA

objects in the database by using a simple query: Query q1 = em.createQuery("SELECT COUNT(p) FROM ... COUNT(p) FROM Point p") instructs JPA to count all the Point objects in the database

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