JPA Query MONTH/YEAR functions

How can I write a JPA query using MONTH function just like sql query?

@NamedQuery(name="querybymonth", query="select t from table1 t where MONTH(c_Date) = 5")

When I use the above pattern for query, I get an开发者_JAVA技巧 error: unexpected token - MONTH.

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If you are using EclipseLink (2.1) you can use the FUNC() function to call any database function that is not defined in the JPA JPQL spec.

i.e. FUNC('MONTH', c_Date)

In JPA 2.1 (EclipseLink 2.5) the FUNCTION syntax becomes part of the specification (and replaces the EclipseLink-specific FUNC).

If you are using TopLink Essentials, you cannot do this in JPQL, but you can define a TopLink Expression query for it (similar to JPA 2.0 criteria), or use native SQL.

Also if you are using any JPA 2.0 provider and using a Criteria query there is a function() API that can be used to define this.

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I want to query YEAR(itemDate) but the function doesn't exit, then i saw the SUBSTRING() function so what i did was Select q from table where SUBSTRING(itemDate, 1, 4)='2011' and it works for me! hope it helps!

if you need you a dynamic variable, you can do that too. here :poDate is the year which is deifned in the setParameter();

@NamedQuery(name = "PurchaseOrders.findByYear", query = "SELECT p FROM PurchaseOrders p WHERE SUBSTRING(p.poDate, 1, 4) = :poDate")

Query q = em.createNamedQuery("PurchaseOrders.findByYear");
q.setParameter("poDate", s_year+"");

but if your okay with your solutions, that'll be fine. i just find JPA faster to execute.

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The MONTH() function exists in Hibernate HQL but is not a standard JPA function. Maybe your JPA provider has some proprietary equivalent but you didn't mention it. If it doesn't, fall back on native SQL.

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I am using Toplink Essentials for the same. Please help, if any function exists in Toplink. Thanks.

To my knowledge, TopLink doesn't have a direct equivalent. So either use a native SQL query or maybe a TopLink Expression query (not sure about this, and not sure this is available in TopLink Essentials).

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Following worked for me with hibernate (4.3.9.Final) & JPA 2.1.

@NamedQuery(name = "PartyEntity.findByAID", query = "select distinct psc.party from PartyShortCode psc where (psc.shortCode = :aidNumber or FUNCTION('REPLACE',psc.accountReference,' ','') = :aidNumber) and psc.sourceSystem in :sourceSystem")

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if your class holds a date type variable, you can use a query like this:

@Query("select m from Movement m where m.id_movement_type.id=1 and SubString(cast(m.date as text),1,4) = :year")
    List<Movement> buysForYear(@Param("year") String year);