Major Description
Join (M)
Joins two inputs based on one or more join conditions. The output of this operator is the combination of the two inputs. This is done by providing a combination record of each set of input records that matches all provided join conditions. In the case that no conditions are provided, a cartesian join is generated. The combination record is a single record that contains a merged map of values from both provided input records. For example, if the left record is
{donuts: [data]}and the right is
{purchases: [data]}, the combination record would be
{donuts: [data], purchases: [data]}. Join also requires a condition type variable which. This describes what happens when a record doesn’t match the join conditions. Inner means only records that match the join conditions should be included. Outer means if a record is
Avaiable relationship types ‘Reltypes’ include: >, >=, <=, <, !=, ==
{ @id†: <opref>, op: “join”,
left: <input>,
right: <input>,
type: <inner|outer|right|left>,
conditions*: [
{relationship: <reltype>, left: <expr>, right: <expr>}
, ...
]
}