How to create node on AgensGraph? - agens-graph

After connected to AgensGraph.
I try to create node on AgensGraph.
But, there is a error on action.
kurt=# create (:v{id:1});
ERROR: graph_path is NULL
HINT: Use SET graph_path
How to set graph_path?


You must create graph, before create vertex(node).
assam=# create graph new_graph;
CREATE GRAPH
After creating graph, set graph_path.
assam=# set graph_path = new_graph;
SET
Finally, You can create a vertex(node).
assam=# create (:v{id:1});
GRAPH WRITE (INSERT VERTEX 1, INSERT EDGE 0)
assam=# match (n:v) return n;
n
-----------------
v[3.1]{"id": 1}
(1 row)

Related

Snowflake - CREATE table with a date variable in its name

I would like to create a table in snowflake, appending the date to the end of its name. What is the best way to do that?
original table = "DB"."SCHEMA"."CLONEME"
desired new table = "DB"."SCHEMA"."CLONEME_20200812BKP"
Tried setting the date variables, but it didn't work.
First attempt:
set var1= (SELECT TO_CHAR(DATE_TRUNC('DAY',CONVERT_TIMEZONE('UTC', CURRENT_DATE())),'YYYYMMDD'));
set var2 = concat('DB.SCHEMA.CLONEME_',$var1);
create table $var2 clone DB.SCHEMA.CLONEME;
-- and got the following error:
-- SQL compilation error: syntax error line 1 at position 13 unexpected '$var2'.

I'd recommend using the IDENTIFIER function:
https://docs.snowflake.com/en/sql-reference/identifier-literal.html
Example:
CREATE OR REPLACE TABLE CLONEME(
src_string VARCHAR(20));
INSERT INTO CLONEME
VALUES('JKNHJYGHTFGRTYGHJ'), ('ABC123'), (null), ('0123456789');
set var1= (SELECT TO_CHAR(DATE_TRUNC('DAY',CONVERT_TIMEZONE('UTC', CURRENT_DATE())),'YYYYMMDD'));
set var2 = concat('CLONEME_',$var1);
SELECT getvariable('VAR1'), getvariable('VAR2');
--20200812 CLONEME_20200812
create table identifier($var2) clone CLONEME;
--Table CLONEME_20200812 successfully created

How to drop property constraint on AgensGraph?

I want to drop property index on AgensGraph.
agens=# create vlabel v;
CREATE VLABEL
agens=# create elabel e;
CREATE ELABEL
agens=# create property index on v ( id );
CREATE PROPERTY INDEX
agens=# create property index on e ( id );
CREATE PROPERTY INDEX
agens=# drop property index on v ( id );
ERROR: syntax error at or near "on"
LINE 1: drop property index on v ( id );
^
agens=# drop property index on e ( id );
ERROR: syntax error at or near "on"
LINE 1: drop property index on e ( id );
^
But, there is some problem on grammar.
How to drop property constraint on AgensGraph?

Name of property index is created automatically at creation time.
You can use '\dGe' and '\dGe' for find structure of labels.
agens=# \dGv v
List of labels
Graph | Name | Type | Owner
-------+------+--------+-------
graph | v | vertex | agens
(1 row)
Vertex label "graph.v"
--
Property Indexes:
"v_id_idx" btree (id)
Inherits: graph.ag_vertex
agens=# \dGe e
List of labels
Graph | Name | Type | Owner
-------+------+------+-------
graph | e | edge | agens
(1 row)
Edge label "graph.e"
--
Property Indexes:
"e_id_idx1" btree (id)
Inherits: graph.ag_edge
After search index name, drop property index next.
agens=# drop property index v_id_idx;
DROP PROPERTY INDEX
agens=# drop property index e_id_idx1;
DROP PROPERTY INDEX

How to find internal vertices in variable-length-edges on AgensGraph?

I tried to find internal vertices in variable-length-edges on AgensGraph.
But, It returns error message like following.
Is there problem on CYPHER query on mime?
How can I view internal vertices of VLE?
Attaching sample script follow.
create graph vle;
create vlabel o;
create vlabel l;
create elabel e;
create property index on o ( id );
create property index on l ( id );
create property index on e ( id );
create (:o{id:1})
create (:o{id:2})
create (:o{id:3})
create (:o{id:4})
create (:o{id:5})
create (:o{id:6})
create (:o{id:7})
create (:o{id:8})
create (:o{id:9});
match (o:o) create (:v{id:o.id});
match (n:v) where n.id >= 1 and n.id <= 9
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+1)}]->(:v{id:n.id*10+1})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+2)}]->(:v{id:n.id*10+2})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+3)}]->(:v{id:n.id*10+3})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+4)}]->(:v{id:n.id*10+4})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+5)}]->(:v{id:n.id*10+5})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+6)}]->(:v{id:n.id*10+6})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+7)}]->(:v{id:n.id*10+7})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+8)}]->(:v{id:n.id*10+8})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+9)}]->(:v{id:n.id*10+9});
match (n:v) where n.id >= 11 and n.id <= 99
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+1)}]->(:v{id:n.id*10+1})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+2)}]->(:v{id:n.id*10+2})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+3)}]->(:v{id:n.id*10+3})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+4)}]->(:v{id:n.id*10+4})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+5)}]->(:v{id:n.id*10+5})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+6)}]->(:v{id:n.id*10+6})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+7)}]->(:v{id:n.id*10+7})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+8)}]->(:v{id:n.id*10+8})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+9)}]->(:v{id:n.id*10+9});
match (n:v) where n.id >= 111 and n.id <= 999
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+1)}]->(:v{id:n.id*10+1})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+2)}]->(:v{id:n.id*10+2})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+3)}]->(:v{id:n.id*10+3})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+4)}]->(:v{id:n.id*10+4})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+5)}]->(:v{id:n.id*10+5})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+6)}]->(:v{id:n.id*10+6})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+7)}]->(:v{id:n.id*10+7})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+8)}]->(:v{id:n.id*10+8})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+9)}]->(:v{id:n.id*10+9});
match (n:v) where n.id >= 1111 and n.id <= 9999
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+1)}]->(:v{id:n.id*10+1})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+2)}]->(:v{id:n.id*10+2})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+3)}]->(:v{id:n.id*10+3})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+4)}]->(:v{id:n.id*10+4})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+5)}]->(:v{id:n.id*10+5})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+6)}]->(:v{id:n.id*10+6})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+7)}]->(:v{id:n.id*10+7})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+8)}]->(:v{id:n.id*10+8})
create (n)-[:e{id:'v:'+n.id+'->v:'+(n.id*10+9)}]->(:v{id:n.id*10+9});
match p = ( (v1:v{id:1})-[:e*]->(v2:v{id:11111}) ) return nodes(p);
ERROR: graph path and variable length edge cannot be used at the same time
LINE 1: match p = ( (v1:v{id:1})-[:e*]->(v2:v{id:11111}) ) return no...
^
Please, help...

It is impossible to get nodes between VLE path on older version of AgensGraph.
Think upgrading version of AgensGraph.
agens (AgensGraph 2.1.0, based on PostgreSQL 10.4)
Type "help" for help.
agens =# match p = ( (v1:v{id:1})-[:e*]->(v2:v{id:11111}) ) return nodes(p);
nodes
----------------------------------------------------------------------------------------------------
[v[6.1]{"id": 1},v[6.10]{"id": 11},v[6.91]{"id": 111},v[6.820]{"id": 1111},v[6.7381]{"id": 11111}]
(1 row)

How can I increase performance of shortest-path on AgensGraph?

I tried to use shortest-path on AgensGraph.
But, It is quietly slower than other graph database.
How can I increase performance of shortest-path on AgensGraph?
I want to some tips or configuration parameters.
Attaching sample script follow.
create graph shortestpath;
create vlabel o;
create vlabel l;
create elabel e;
create property index on o ( id );
create property index on l ( id );
create property index on e ( id );
create (:o{id:1})
create (:o{id:2})
create (:o{id:3})
create (:o{id:4})
create (:o{id:5})
create (:o{id:6})
create (:o{id:7})
create (:o{id:8})
create (:o{id:9});
match (o:o) create (:l{id:o.id});
match (n:l) where n.id >= 1 and n.id <= 9
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+1)}]->(:l{id:n.id*10+1})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+2)}]->(:l{id:n.id*10+2})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+3)}]->(:l{id:n.id*10+3})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+4)}]->(:l{id:n.id*10+4})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+5)}]->(:l{id:n.id*10+5})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+6)}]->(:l{id:n.id*10+6})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+7)}]->(:l{id:n.id*10+7})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+8)}]->(:l{id:n.id*10+8})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+9)}]->(:l{id:n.id*10+9});
match (n:l) where n.id >= 11 and n.id <= 99
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+1)}]->(:l{id:n.id*10+1})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+2)}]->(:l{id:n.id*10+2})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+3)}]->(:l{id:n.id*10+3})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+4)}]->(:l{id:n.id*10+4})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+5)}]->(:l{id:n.id*10+5})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+6)}]->(:l{id:n.id*10+6})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+7)}]->(:l{id:n.id*10+7})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+8)}]->(:l{id:n.id*10+8})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+9)}]->(:l{id:n.id*10+9});
match (n:l) where n.id >= 111 and n.id <= 999
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+1)}]->(:l{id:n.id*10+1})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+2)}]->(:l{id:n.id*10+2})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+3)}]->(:l{id:n.id*10+3})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+4)}]->(:l{id:n.id*10+4})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+5)}]->(:l{id:n.id*10+5})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+6)}]->(:l{id:n.id*10+6})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+7)}]->(:l{id:n.id*10+7})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+8)}]->(:l{id:n.id*10+8})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+9)}]->(:l{id:n.id*10+9});
match (n:l) where n.id >= 1111 and n.id <= 9999
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+1)}]->(:l{id:n.id*10+1})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+2)}]->(:l{id:n.id*10+2})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+3)}]->(:l{id:n.id*10+3})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+4)}]->(:l{id:n.id*10+4})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+5)}]->(:l{id:n.id*10+5})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+6)}]->(:l{id:n.id*10+6})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+7)}]->(:l{id:n.id*10+7})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+8)}]->(:l{id:n.id*10+8})
create (n)-[:e{id:'l:'+n.id+'->l:'+(n.id*10+9)}]->(:l{id:n.id*10+9});
\timing
match p = allshortestpaths( (l1:l)-[:e*]->(l2:l) ) where l1.id = 1 and l2.id = 11111 return l1.id as l1id, l2.id as l2id, count(p) order by l1id, l2id;
l1id | l2id | count
------+-------+-------
1 | 11111 | 1
(1 row)
Time: 133.547 ms
Is it possible that improve to under 10ms.

There is an improvement on Shortest-Path on "AgensGraph Version 2.1".
Algorithm is changed to "Bidirectional BFS" from "BFS".
agens (AgensGraph 2.1.0, based on PostgreSQL 10.4)
Type "help" for help.
match p = allshortestpaths( (l1:l)-[:e*]->(l2:l) ) where l1.id = 1 and l2.id = 11111 return l1.id as l1id, l2.id as l2id, count(p) order by l1id, l2id;
l1id | l2id | count
------+-------+-------
1 | 11111 | 1
(1 row)
Time: 1.776 ms
If you use "Version 1.3" or "Version 2.0", It is better choice upgrade to "Version 2.1"

How to delete node on AgensGraph?

I try to delete node on agens graph and failed.
lee=# match (n:v{id:1}) delete n;
ERROR: vertex 4 in "v" has edge(s)
How to delete node?

Add detach before delete token.
assam=# match (n:v{id:1}) detach delete n;
GRAPH WRITE (DELETE VERTEX 1, DELETE EDGE 1)

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