java - JPA 2.0, Write query with multiple conditionals -

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i have entity fields

@entity public myentity {      @id     @generatedvalue(strategy = generationtype.identity)     public long id;      public uuid uuid;      public string value;      .....  }

now create query returns 1 if there @ least x entities in database same uuid, or returns 2 if there @ least y entities same uuid , have same value. im not sure if described well. if in java collection following code:

int b = 0; string y = ..; uuid x = ...; list<myentity> list = getallentitieswithsameuuid(x) if (list.sze() == 50) return 1  (myentity e : list) {     if (e.value.equalsignorecase(y)) {         b++;         if (b == 100) {             return 2;         }     } }

in case have process tons of data, move processing database server , in application retrieve integer result of query.

can use jpa's query, criteriaquery, (something else) achieve this? i'm using jpa 2.0, , hibernate 4.

i use 2 queries , combine both in java:

string value = ..; uuid uuid = ...;  number uuidcount = entitymanager.createquery(         "select count(e) myentity e e.uuid = :uuid").setparameter(         "uuid", uuid).getsingleresult(); if (uuidcount.longvalue() == 50) {     return 1; }  number uuidandvaluecount = entitymanager.createquery(         "select count(e) myentity e e.uuid = :uuid , e.value = :value").setparameter(         "uuid", uuid).setparameter("value", value).getsingleresult(); if (uuidandvaluecount.longvalue() == 100) {    return 2; }

i think performance difference of 1 catch all query compared 2 separate queries minimal. depending on execution plan may happen solution faster, need fire second query only, if first fails.


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