# Reference operators¶

NGQL provides reference operators to represent a property in a WHERE or YIELD clause, or the output of the statement before the pipe symbol in a composite query.

## Reference operator List¶

Reference operator Description
$^ Refers to a source vertex property. For more information, see Property reference. $$ Refers to a destination vertex property. For more information, see Property reference. - Refers to the output of the statement before the pipe symbol in a composite query. For more information, see Pipe. ## Examples¶ The following example returns the age of the source vertex and the destination vertex. nebula> GO FROM "player100" OVER follow \ YIELD ^.player.age AS SrcAge,$$.player.age AS DestAge; +--------+---------+ | SrcAge | DestAge | +--------+---------+ | 42 | 36 | +--------+---------+ | 42 | 41 | +--------+---------+  The following example returns the name and team of the players that "player100" follows. nebula> GO FROM "player100" OVER follow \ YIELD follow._dst AS id | \ GO FROM$-.id OVER serve \
YIELD $^.player.name AS Player,$\$.team.name AS Team;
+-----------------+-----------+
| Player          | Team      |
+-----------------+-----------+
| "Tony Parker"   | "Spurs"   |
+-----------------+-----------+
| "Tony Parker"   | "Hornets" |
+-----------------+-----------+
| "Manu Ginobili" | "Spurs"   |
+-----------------+-----------+


Last update: March 23, 2021