Find max value in table column

Question

I am creating a version control domain class in Grails:

class VersionControl {

    Date dateCreated
    Long versionNumber

    Long getLatestVersionNumber() {
        //return largest versionNumber
    }

}

I would like to add a query to get the largest version number stored:

Long getLatestVersionNumber()

In SQL this query would look more or less as follows:

SELECT TOP 1 MAX(versionNumber) FROM VersionControl

The function MUST return the value as a long.

What is the correct way to do this in Grails?

Answer 1

You can use GORM criteria, querying with projections:

VersionControl.createCriteria().get {
    projections {
        max "versionNumber"
    }
} as Long

Answer 2

VersionControl.executeQuery("select max(versionNumber) from VersionControl")

This is easier for me to understand.