Union
Union( group, ... )Description
The Union function combines the results of one or more groups, which
can be Arrays or
Set References.
Parameters
| Argument | Type | Definition and Requirements |
|---|---|---|
|
One or more arrays or set references which should have their results OR’d
together. All provided |
Returns
When group is an array, an array of the items that appear in any
provided group.
When group is a set reference, a set reference of the items that appear in any
provided group.
Examples
The following query combines the Set Reference (i.e. set reference)
returned by locating the search term "fire" in the index named
"spells_by_element" and the Set Reference returned by locating the
search term "water" in the Index named "spells_by_element". The
Paginate function materialized the
results of the Union operation into an array of type Page.
client.query(
q.Paginate(
q.Union(
q.Match(q.Index('spells_by_element'), 'fire'),
q.Match(q.Index('spells_by_element'), 'water'),
)
)
)
.then((ret) => console.log(ret)){ data:
[ Ref(id=181388642046968320, collection=Ref(id=spells, collection=Ref(id=collections))),
Ref(id=181388642071085568, collection=Ref(id=spells, collection=Ref(id=collections))),
Ref(id=181388642088911360, collection=Ref(id=spells, collection=Ref(id=collections))) ] }The query below is similar to the example above, but it returns document events instead of the index tuples.
client.query(
q.Paginate(
q.Events(
q.Union(
q.Match(q.Index('spells_by_element'), 'fire'),
q.Match(q.Index('spells_by_element'), 'water'),
)
)
)
)
.then((ret) => console.log(ret)){ data:
[ { ts: 1526677776479051,
action: 'add',
document:
Ref(id=181388642046968320, collection=Ref(id=spells, collection=Ref(id=collections))) },
{ ts: 1526677776479051,
action: 'add',
document:
Ref(id=181388642071085568, collection=Ref(id=spells, collection=Ref(id=collections))) },
{ ts: 1527095201753208,
action: 'add',
document:
Ref(id=181388642088911360, collection=Ref(id=spells, collection=Ref(id=collections))) } ] }The following query demonstrates how various arrays are evaluated:
client.query([
q.Union(['A', 'B'], ['C', 'D']),
q.Union(['A', 'B'], ['B', 'C']),
q.Union(['A', 'B', 'C'], ['B', 'C'], ['B', 'C', 'D']),
q.Union(['A', 'B', 'C'], ['B', 'B'], ['B']),
])
.then((ret) => console.log(ret))[ [ 'A', 'B', 'C', 'D' ],
[ 'A', 'B', 'C' ],
[ 'A', 'B', 'C', 'D' ],
[ 'A', 'B', 'B', 'C' ] ]Is this article helpful?
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