gremlin-python drop multiple vertices and edges in one transaction
My context:
- gremlin-python
- AWS Neptune
My question is:
1) Can I drop vertices and edges recursively in one transaction given that I have all the specific ids of the vertices and edges I want to drop? The aim is to write python function that evaluates each edge, and determine whether it needs to be dropped, and chain a gremlin query to drop it.
For instance:
vertex ids to delete:
'vertex1', 'vertex2', 'vertex3'
edge ids to delete:
'edge1', 'edge2', 'edge3'
An example of the python function to chain on to g would be like:
def chain_drop(g, vertex_id):
g = g.V(vertex_id).drop()
return g
The chained query i would like to execute as one transaction would ideally look something like:
g.E('edge1').drop()
.V('vertex1').drop()
.E('edge3').drop()
.V('vertex3').drop()
.iterate() # execute all these queries as one transaction
The above doesn't work... And it seems I cannot .E('someid') in the middle of my gremlin query.
Slightly off topic but my best try (non-recursive) would be something like below:
g.E('edge1', 'edge2', 'edge3').as_('edges')
.V('vertex1', 'vertex2', 'vertex3').as_('vertices')
.union(__.select('edges'),
__.select('vertices'))
.drop()
.iterate()
Any help much appreciated!
python gremlin amazon-neptune
asked Nov 22 at 14:21
Matthew Tan
31
add a comment |
My context:
- gremlin-python
- AWS Neptune
My question is:
1) Can I drop vertices and edges recursively in one transaction given that I have all the specific ids of the vertices and edges I want to drop? The aim is to write python function that evaluates each edge, and determine whether it needs to be dropped, and chain a gremlin query to drop it.
For instance:
vertex ids to delete:
'vertex1', 'vertex2', 'vertex3'
edge ids to delete:
'edge1', 'edge2', 'edge3'
An example of the python function to chain on to g would be like:
def chain_drop(g, vertex_id):
g = g.V(vertex_id).drop()
return g
The chained query i would like to execute as one transaction would ideally look something like:
g.E('edge1').drop()
.V('vertex1').drop()
.E('edge3').drop()
.V('vertex3').drop()
.iterate() # execute all these queries as one transaction
The above doesn't work... And it seems I cannot .E('someid') in the middle of my gremlin query.
Slightly off topic but my best try (non-recursive) would be something like below:
g.E('edge1', 'edge2', 'edge3').as_('edges')
.V('vertex1', 'vertex2', 'vertex3').as_('vertices')
.union(__.select('edges'),
__.select('vertices'))
.drop()
.iterate()
Any help much appreciated!
python gremlin amazon-neptune
asked Nov 22 at 14:21
Matthew Tan
31
add a comment |
My context:
- gremlin-python
- AWS Neptune
My question is:
1) Can I drop vertices and edges recursively in one transaction given that I have all the specific ids of the vertices and edges I want to drop? The aim is to write python function that evaluates each edge, and determine whether it needs to be dropped, and chain a gremlin query to drop it.
For instance:
vertex ids to delete:
'vertex1', 'vertex2', 'vertex3'
edge ids to delete:
'edge1', 'edge2', 'edge3'
An example of the python function to chain on to g would be like:
def chain_drop(g, vertex_id):
g = g.V(vertex_id).drop()
return g
The chained query i would like to execute as one transaction would ideally look something like:
g.E('edge1').drop()
.V('vertex1').drop()
.E('edge3').drop()
.V('vertex3').drop()
.iterate() # execute all these queries as one transaction
The above doesn't work... And it seems I cannot .E('someid') in the middle of my gremlin query.
Slightly off topic but my best try (non-recursive) would be something like below:
g.E('edge1', 'edge2', 'edge3').as_('edges')
.V('vertex1', 'vertex2', 'vertex3').as_('vertices')
.union(__.select('edges'),
__.select('vertices'))
.drop()
.iterate()
Any help much appreciated!
python gremlin amazon-neptune
asked Nov 22 at 14:21
Matthew Tan
31
My context:
- gremlin-python
- AWS Neptune
My question is:
1) Can I drop vertices and edges recursively in one transaction given that I have all the specific ids of the vertices and edges I want to drop? The aim is to write python function that evaluates each edge, and determine whether it needs to be dropped, and chain a gremlin query to drop it.
For instance:
vertex ids to delete:
'vertex1', 'vertex2', 'vertex3'
edge ids to delete:
'edge1', 'edge2', 'edge3'
An example of the python function to chain on to g would be like:
def chain_drop(g, vertex_id):
g = g.V(vertex_id).drop()
return g
The chained query i would like to execute as one transaction would ideally look something like:
g.E('edge1').drop()
.V('vertex1').drop()
.E('edge3').drop()
.V('vertex3').drop()
.iterate() # execute all these queries as one transaction
The above doesn't work... And it seems I cannot .E('someid') in the middle of my gremlin query.
Slightly off topic but my best try (non-recursive) would be something like below:
g.E('edge1', 'edge2', 'edge3').as_('edges')
.V('vertex1', 'vertex2', 'vertex3').as_('vertices')
.union(__.select('edges'),
__.select('vertices'))
.drop()
.iterate()
Any help much appreciated!
python gremlin amazon-neptune
python gremlin amazon-neptune
asked Nov 22 at 14:21
Matthew Tan
31
asked Nov 22 at 14:21
Matthew Tan
31
asked Nov 22 at 14:21
Matthew Tan
31
asked Nov 22 at 14:21
Matthew Tan
31
asked Nov 22 at 14:21
Matthew Tan
31
31
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
You can't do what you want to do exactly for two reasons:
- There is no mid-traversal
E()as it is a start step only.
drop()is kills all traversers so the mid-traversalV()following it won't ever get executed.
You can take a different approach however and simply gather all of your elements to remove and then then drop those...something like:
g.V(1).aggregate('x').V(2).aggregate('x').select('x').unfold().drop()
Note that dropping vertices will also drop edges so if those edges you want to drop are connected to the vertices you want to drop you don't need to drop them explicitly.
answered Nov 22 at 14:45
stephen mallette
24.9k32776
Thank you Stephen for the clarification and the pointers! I've gotten around dropping Edges and Vertices in the same query by doing so:g.E('edge1, 'edge2', 'edge3').aggregate('x').fold() .V(1).aggregate('x').V(2).aggregate('x') .select('x').unfold().drop()
– Matthew Tan
Nov 23 at 15:05
do you need tofold()? i wouldn't think so.aggregate()is greedy step so it should collect all edges without need tofold()anything
– stephen mallette
Nov 23 at 17:40
I did the fold() as a trick to reduce 3 traversers to one. Then subsequent chained steps only get called on the one traverser. But you're right, it doesn't change the result I think...
– Matthew Tan
Nov 24 at 9:26
you're right. i'd forgotten that the mid-traversalV()will get called once per traverser.
– stephen mallette
Nov 24 at 12:51
add a comment |
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1 Answer
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1 Answer
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oldest
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oldest
votes
You can't do what you want to do exactly for two reasons:
- There is no mid-traversal
E()as it is a start step only.
drop()is kills all traversers so the mid-traversalV()following it won't ever get executed.
You can take a different approach however and simply gather all of your elements to remove and then then drop those...something like:
g.V(1).aggregate('x').V(2).aggregate('x').select('x').unfold().drop()
Note that dropping vertices will also drop edges so if those edges you want to drop are connected to the vertices you want to drop you don't need to drop them explicitly.
answered Nov 22 at 14:45
stephen mallette
24.9k32776
Thank you Stephen for the clarification and the pointers! I've gotten around dropping Edges and Vertices in the same query by doing so:g.E('edge1, 'edge2', 'edge3').aggregate('x').fold() .V(1).aggregate('x').V(2).aggregate('x') .select('x').unfold().drop()
– Matthew Tan
Nov 23 at 15:05
do you need tofold()? i wouldn't think so.aggregate()is greedy step so it should collect all edges without need tofold()anything
– stephen mallette
Nov 23 at 17:40
I did the fold() as a trick to reduce 3 traversers to one. Then subsequent chained steps only get called on the one traverser. But you're right, it doesn't change the result I think...
– Matthew Tan
Nov 24 at 9:26
you're right. i'd forgotten that the mid-traversalV()will get called once per traverser.
– stephen mallette
Nov 24 at 12:51
add a comment |
You can't do what you want to do exactly for two reasons:
- There is no mid-traversal
E()as it is a start step only.
drop()is kills all traversers so the mid-traversalV()following it won't ever get executed.
You can take a different approach however and simply gather all of your elements to remove and then then drop those...something like:
g.V(1).aggregate('x').V(2).aggregate('x').select('x').unfold().drop()
Note that dropping vertices will also drop edges so if those edges you want to drop are connected to the vertices you want to drop you don't need to drop them explicitly.
answered Nov 22 at 14:45
stephen mallette
24.9k32776
Thank you Stephen for the clarification and the pointers! I've gotten around dropping Edges and Vertices in the same query by doing so:g.E('edge1, 'edge2', 'edge3').aggregate('x').fold() .V(1).aggregate('x').V(2).aggregate('x') .select('x').unfold().drop()
– Matthew Tan
Nov 23 at 15:05
do you need tofold()? i wouldn't think so.aggregate()is greedy step so it should collect all edges without need tofold()anything
– stephen mallette
Nov 23 at 17:40
I did the fold() as a trick to reduce 3 traversers to one. Then subsequent chained steps only get called on the one traverser. But you're right, it doesn't change the result I think...
– Matthew Tan
Nov 24 at 9:26
you're right. i'd forgotten that the mid-traversalV()will get called once per traverser.
– stephen mallette
Nov 24 at 12:51
add a comment |
You can't do what you want to do exactly for two reasons:
- There is no mid-traversal
E()as it is a start step only.
drop()is kills all traversers so the mid-traversalV()following it won't ever get executed.
You can take a different approach however and simply gather all of your elements to remove and then then drop those...something like:
g.V(1).aggregate('x').V(2).aggregate('x').select('x').unfold().drop()
Note that dropping vertices will also drop edges so if those edges you want to drop are connected to the vertices you want to drop you don't need to drop them explicitly.
answered Nov 22 at 14:45
stephen mallette
24.9k32776
You can't do what you want to do exactly for two reasons:
- There is no mid-traversal
E()as it is a start step only.
drop()is kills all traversers so the mid-traversalV()following it won't ever get executed.
You can take a different approach however and simply gather all of your elements to remove and then then drop those...something like:
g.V(1).aggregate('x').V(2).aggregate('x').select('x').unfold().drop()
Note that dropping vertices will also drop edges so if those edges you want to drop are connected to the vertices you want to drop you don't need to drop them explicitly.
answered Nov 22 at 14:45
stephen mallette
24.9k32776
answered Nov 22 at 14:45
stephen mallette
24.9k32776
answered Nov 22 at 14:45
stephen mallette
24.9k32776
answered Nov 22 at 14:45
stephen mallette
24.9k32776
24.9k32776
Thank you Stephen for the clarification and the pointers! I've gotten around dropping Edges and Vertices in the same query by doing so:g.E('edge1, 'edge2', 'edge3').aggregate('x').fold() .V(1).aggregate('x').V(2).aggregate('x') .select('x').unfold().drop()
– Matthew Tan
Nov 23 at 15:05
do you need tofold()? i wouldn't think so.aggregate()is greedy step so it should collect all edges without need tofold()anything
– stephen mallette
Nov 23 at 17:40
I did the fold() as a trick to reduce 3 traversers to one. Then subsequent chained steps only get called on the one traverser. But you're right, it doesn't change the result I think...
– Matthew Tan
Nov 24 at 9:26
you're right. i'd forgotten that the mid-traversalV()will get called once per traverser.
– stephen mallette
Nov 24 at 12:51
add a comment |
Thank you Stephen for the clarification and the pointers! I've gotten around dropping Edges and Vertices in the same query by doing so:g.E('edge1, 'edge2', 'edge3').aggregate('x').fold() .V(1).aggregate('x').V(2).aggregate('x') .select('x').unfold().drop()
– Matthew Tan
Nov 23 at 15:05
do you need tofold()? i wouldn't think so.aggregate()is greedy step so it should collect all edges without need tofold()anything
– stephen mallette
Nov 23 at 17:40
I did the fold() as a trick to reduce 3 traversers to one. Then subsequent chained steps only get called on the one traverser. But you're right, it doesn't change the result I think...
– Matthew Tan
Nov 24 at 9:26
you're right. i'd forgotten that the mid-traversalV()will get called once per traverser.
– stephen mallette
Nov 24 at 12:51
Thank you Stephen for the clarification and the pointers! I've gotten around dropping Edges and Vertices in the same query by doing so:
g.E('edge1, 'edge2', 'edge3').aggregate('x').fold() .V(1).aggregate('x').V(2).aggregate('x') .select('x').unfold().drop()– Matthew Tan
Nov 23 at 15:05
Thank you Stephen for the clarification and the pointers! I've gotten around dropping Edges and Vertices in the same query by doing so:
g.E('edge1, 'edge2', 'edge3').aggregate('x').fold() .V(1).aggregate('x').V(2).aggregate('x') .select('x').unfold().drop()– Matthew Tan
Nov 23 at 15:05
do you need to
fold()? i wouldn't think so. aggregate() is greedy step so it should collect all edges without need to fold() anything– stephen mallette
Nov 23 at 17:40
do you need to
fold()? i wouldn't think so. aggregate() is greedy step so it should collect all edges without need to fold() anything– stephen mallette
Nov 23 at 17:40
I did the fold() as a trick to reduce 3 traversers to one. Then subsequent chained steps only get called on the one traverser. But you're right, it doesn't change the result I think...
– Matthew Tan
Nov 24 at 9:26
I did the fold() as a trick to reduce 3 traversers to one. Then subsequent chained steps only get called on the one traverser. But you're right, it doesn't change the result I think...
– Matthew Tan
Nov 24 at 9:26
you're right. i'd forgotten that the mid-traversal
V() will get called once per traverser.– stephen mallette
Nov 24 at 12:51
you're right. i'd forgotten that the mid-traversal
V() will get called once per traverser.– stephen mallette
Nov 24 at 12:51
add a comment |
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