mirror of https://gitee.com/bigwinds/arangodb
68 lines
2.1 KiB
Markdown
68 lines
2.1 KiB
Markdown
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Pregel Subsystem
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========
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The pregel subsystem implements a variety of different grapg algorithms,
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this readme is more intended for internal use.
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#### Protocol
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Message format between DBServers:
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{sender:"someid",
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executionNumber:1337,
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globalSuperstep:123,
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messages: [<vertexID1>, <slice1>, vertexID2, <slice2>]
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}
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Any type of slice is supported
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### Useful Commands
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Import graph e.g. https://github.com/arangodb/example-datasets/tree/master/Graphs/1000
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First rename the columns '_key', '_from', '_to' arangoimport will keep those.
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In arangosh:
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db._create('vertices', {numberOfShards: 2});
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db._createEdgeCollection('alt_edges');
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db._createEdgeCollection('edges', {numberOfShards: 2, shardKeys:["_vertex"], distributeShardsLike:'vertices'});
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arangoimport --file generated_vertices.csv --type csv --collection vertices --overwrite true --server.endpoint http+tcp://127.0.0.1:8530
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Or:
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for(var i=0; i < 5000; i++) db.vertices.save({_key:i+""});
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arangoimport --file generated_edges.csv --type csv --collection alt_edges --overwrite true --from-collection-prefix "vertices" --to-collection-prefix "vertices" --convert false --server.endpoint http+tcp://127.0.0.1:8530
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AQL script to copy edge collection into one with '_vertex':
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FOR doc IN alt_edges
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INSERT {_vertex:SUBSTRING(doc._from,FIND_FIRST(doc._from,"/")+1),
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_from:doc._from,
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_to:doc._to} IN edges
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LET values = (
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FOR s IN vertices
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RETURN s.result
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)
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RETURN SUM(values)
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# AWK Scripts
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Make CSV file with ID’s unique
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cat edges.csv | tr '[:space:]' '[\n*]' | grep -v "^\s*$" | awk '!seen[$0]++' > vertices.csv
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Make CSV file with arango compatible edges
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cat edges.csv | awk -F" " '{print "profiles/" $1 "\tprofiles/" $2 "\t" $1}' >> arango-edges.csv
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arangoimport --file vertices.csv --type csv --collection twitter_v --overwrite true --convert false --server.endpoint http+tcp://127.0.0.1:8530 -c none
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arangoimport --file arango-edges.csv --type csv --collection twitter_e --overwrite true --convert false --separator "\t" --server.endpoint http+tcp://127.0.0.1:8530 -c none
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