如何为Gremlin-Python中批量选中的顶点添加不同属性值？

Great question! You’re already on the right track with selecting multiple vertices at once using g.V([1, 2, 3])—and yes, it’s totally possible to assign different property values to each of those vertices in a single Gremlin query. Here are two practical approaches depending on your use case:

Approach 1: Batch Key-Value Pairs (Scalable for Larger Datasets) #

If you have a list of ID-value pairs you want to apply, using inject + unfold lets you process all pairs in one go. This is ideal if you’re working with more than just a handful of vertices:

from gremlin_python.process.traversal import Column

# Define your ID-value mappings
id_value_pairs = [(1, 'a'), (2, 'b'), (3, 'c')]

# Execute the batch property update
g.inject(id_value_pairs).unfold().as_('pair').
    V(select('pair').by(Column.keys)).
    property('x', select('pair').by(Column.values)).
    iterate()

How this works: #

1. inject(id_value_pairs) passes your list of mappings into the traversal.
2. unfold() breaks the list into individual (ID, value) pairs.
3. as_('pair') labels each pair so we can reference it later.
4. V(select('pair').by(Column.keys)) selects the vertex matching the ID from the current pair.
5. property('x', select('pair').by(Column.values)) sets the x property to the corresponding value.
6. iterate() runs the traversal without returning results (since we’re only modifying data).

Approach 2: Hardcoded Choices (For Smaller, Fixed Sets) #

If you only have a few vertices and want a more explicit, readable query, use choose to branch based on vertex ID:

from gremlin_python.process.traversal import eq

g.V([1, 2, 3]).choose(id(),
    eq(1).property('x', 'a'),
    eq(2).property('x', 'b'),
    eq(3).property('x', 'c')).
    iterate()

This traversal checks each selected vertex’s ID, then applies the matching property value directly. It’s straightforward for small sets but becomes unwieldy if you have dozens of vertices to update.

Both approaches will achieve exactly what you’re looking for—no need to run separate queries for each vertex!

内容的提问来源于stack exchange，提问作者simbamford