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Editorial Team
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Asked: 2026-05-16T01:37:53+00:00

I’m using Hibernate to retrieve the number of rows for a specific query. Let’s

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I’m using Hibernate to retrieve the number of rows for a specific query. Let’s say I have a table called ‘Person’ with various columns. One of those columns is ‘name’.

If I wanted to get the number of people with the name of ‘Andrew’, which of these ways would be most efficient? Assuming there is a performance difference between some/all of them. Is there a better way to do this using Hibernate/SQL?

(1) Select all columns

Query query = session.createQuery("from Person where name= :name");
query.setParameter("name", name);
List result = query.list();
int count = result.size();

(2) Select just the name column

Query query = session.createQuery("select name from Person where name= :name");
query.setParameter("name", name);
List result = query.list();
int count = result.size();

(3) Using Count in the query

Query query = session.createQuery("select count(*) from Person where name= :name");
query.setParameter("name", name);
long count = (Long) query.uniqueResult();

(4) Using Count with the name column in the query

Query query = session.createQuery("select count(name) from Person where name= :name");
query.setParameter("name", name);
long count = (Long) query.uniqueResult();

Edit: Sorry, I had two number 3’s in my list

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1 Answer

  1. Editorial Team

    Don’t retrieve a result set if you just want to count the number of rows, this just means useless overhead:

    • you’ll get more stuff than actually wanted (whether you’re selecting all columns or just one)
    • you’ll need to send them over the wire
    • you’ll need to create instances (whether it’s a full Person entity or just a String) for nothing.

    In other words, if you only want to count, don’t do it on the Java side, DBMS are optimized for this task and will do a much better job.

    This excludes (1) and (2).

    Regarding (3) and (4), note that there is a difference between count(*) and count(col) in general:

    • count(*) counts ALL rows
    • count(col) counts rows with non-null values of col

    So they will give different results in performance and query result if col can be NULL (the count(*) being faster), otherwise identical performance.

    I’d use (3).

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