## org.hibernate.criterion
Class Projections

    java.lang.Object
      org.hibernate.criterion.Projections

    public final class Projections

extends Object

The `criterion` package may be used by applications as a framework for building new kinds of `Projection`. However, it is intended that most applications will simply use the built-in projection types via the static factory methods of this class.
The factory methods that take an alias allow the projected value to be referred to by criterion and order instances.

See Also:
  `Criteria`, `factory methods for `Criterion` instances`

Method Summary
`static Projection` `alias(Projection projection, String alias)` Assign an alias to a projection, by wrapping it
`static AggregateProjection` `avg(String propertyName)` A property average value
`static CountProjection` `count(String propertyName)` A property value count
`static CountProjection` `countDistinct(String propertyName)` A distinct property value count
`static Projection` `distinct(Projection proj)` Create a distinct projection from a projection
`static PropertyProjection` `groupProperty(String propertyName)` A grouping property value
`static IdentifierProjection` `id()` A projected identifier value
`static AggregateProjection` `max(String propertyName)` A property maximum value
`static AggregateProjection` `min(String propertyName)` A property minimum value
`static ProjectionList` `projectionList()` Create a new projection list
`static PropertyProjection` `property(String propertyName)` A projected property value
`static Projection` `rowCount()` The query row count, ie.
`static Projection` `sqlGroupProjection(String sql, String groupBy, String[] columnAliases, Type[] types)` A grouping SQL projection, specifying both select clause and group by clause fragments
`static Projection` `sqlProjection(String sql, String[] columnAliases, Type[] types)` A SQL projection, a typed select clause fragment
`static AggregateProjection` `sum(String propertyName)` A property value sum

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Method Detail

### distinct

    public static Projection distinct(Projection proj)

  Create a distinct projection from a projection

### projectionList

    public static ProjectionList projectionList()

  Create a new projection list

### rowCount

    public static Projection rowCount()

  The query row count, ie. `count(*)`

### count

    public static CountProjection count(String propertyName)

  A property value count

### countDistinct

    public static CountProjection countDistinct(String propertyName)

  A distinct property value count

### max

    public static AggregateProjection max(String propertyName)

  A property maximum value

### min

    public static AggregateProjection min(String propertyName)

  A property minimum value

### avg

    public static AggregateProjection avg(String propertyName)

  A property average value

### sum

    public static AggregateProjection sum(String propertyName)

  A property value sum

### sqlProjection

    public static Projection sqlProjection(String sql,
                                           String[] columnAliases,
                                           Type[] types)

  A SQL projection, a typed select clause fragment

### sqlGroupProjection

    public static Projection sqlGroupProjection(String sql,
                                                String groupBy,
                                                String[] columnAliases,
                                                Type[] types)

  A grouping SQL projection, specifying both select clause and group by clause fragments

### groupProperty

    public static PropertyProjection groupProperty(String propertyName)

  A grouping property value

### property

    public static PropertyProjection property(String propertyName)

  A projected property value

### id

    public static IdentifierProjection id()

  A projected identifier value

### alias

    public static Projection alias(Projection projection,
                                   String alias)

  Assign an alias to a projection, by wrapping it

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