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142

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
137

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 ObjDBUser3 Manoj
137

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
86

count(x)

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
78

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
30

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
29

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
28

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
26

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
20

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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