org.apache.calcite.linq4j

Enum JoinType

java.lang.Object

java.lang.Enum<JoinType>

org.apache.calcite.linq4j.JoinType

All Implemented Interfaces:

Serializable, Comparable<JoinType>

public enum JoinType
extends Enum<JoinType>

Enumeration of join types.

Enum Constant Summary

Enum Constants

Enum Constant and Description
ANTI Anti-join (also known as Anti-semi-join).
FULL Full-outer join.
INNER Inner join.
LEFT Left-outer join.
RIGHT Right-outer join.
SEMI Semi-join.

Method Summary

Modifier and Type	Method and Description
boolean	generatesNullsOnLeft() Returns whether a join of this type may generate NULL values on the left-hand side.
boolean	generatesNullsOnRight() Returns whether a join of this type may generate NULL values on the right-hand side.
static JoinType	valueOf(String name) Returns the enum constant of this type with the specified name.
static JoinType[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

INNER

public static final JoinType INNER

Inner join.

LEFT

public static final JoinType LEFT

Left-outer join.

RIGHT

public static final JoinType RIGHT

Right-outer join.

FULL

public static final JoinType FULL

Full-outer join.

SEMI

public static final JoinType SEMI

Semi-join.

For example, EMP semi-join DEPT finds all EMP records that have a corresponding DEPT record:

 SELECT * FROM EMP
 WHERE EXISTS (SELECT 1 FROM DEPT
     WHERE DEPT.DEPTNO = EMP.DEPTNO)

ANTI

public static final JoinType ANTI

Anti-join (also known as Anti-semi-join).

For example, EMP anti-join DEPT finds all EMP records that do not have a corresponding DEPT record:

 SELECT * FROM EMP
 WHERE NOT EXISTS (SELECT 1 FROM DEPT
     WHERE DEPT.DEPTNO = EMP.DEPTNO)

Method Detail

values

public static JoinType[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (JoinType c : JoinType.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static JoinType valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

generatesNullsOnRight

public boolean generatesNullsOnRight()

Returns whether a join of this type may generate NULL values on the right-hand side.

generatesNullsOnLeft

public boolean generatesNullsOnLeft()

Returns whether a join of this type may generate NULL values on the left-hand side.