QueryingClausesPROFILE

PROFILE clause

When improving your query performance, one of the most important aspects is PROFILE clause. The profile clause will return detail information about the execution and how the query plan is interacting with data.

A simple example to illustrate the output:

PROFILE MATCH (n :Node)-[:Edge]-(m :Node) WHERE n.prop = 42 RETURN *;
+-----------------------------------------+---------------+---------------+---------------+
| OPERATOR                                | ACTUAL HITS   | RELATIVE TIME | ABSOLUTE TIME |
+-----------------------------------------+---------------+---------------+---------------+
| * Produce {m, n}                        | 1             |   7.134628 %  |   0.003949 ms |
| * Filter (n :Node), {n.prop}            | 1             |  12.734765 %  |   0.007049 ms |
| * Expand (m)-[anon1:Edge]-(n)           | 1             |   5.181460 %  |   0.002868 ms |
| * ScanAll (n)                           | 1             |   3.325061 %  |   0.001840 ms |
| * ScanAll (m)                           | 1             |  71.061241 %  |   0.039334 ms |
| * Once                                  | 2             |   0.562844 %  |   0.000312 ms |
+-----------------------------------------+---------------+---------------+---------------+

For every logical operator, the following info is provided:

  • OPERATOR — the name of the operator, just like in the output of an EXPLAIN query. Here is the full list of operators. Each operator is usually based on the Cypher clauses used in the query.

  • ACTUAL HITS — the number of times a particular operator was pulled from. This is similar to the number of objects being passed in the query. The lower the number, the better the performance of the query will be since the query will touch and pass less data in the pipeline.

  • RELATIVE TIME — the amount of time that was spent processing a particular logical operator relative to the execution of the whole plan. This will give you the information on where the bottleneck in the query is.

  • ABSOLUTE TIME — the amount of time that was spent processing a particular logical operator. This is wall time, which gives you an idea of how operators spend wall time performing some operations.

OPTIONAL MATCHREMOVE