Profile queries
If a query is prepended with EXPLAIN
, the server will return the execution plan it would use to run it, but not actually execute it.
On the other hand, if a query is prepended with PROFILE
, the server will return the execution plan and the corresponding query result.
The execution plan is valuable in analyzing a query and profiling its performance. For more information, see Execution plans and query tuning.
Example request
POST http://localhost:7474/db/neo4j/query/v2
Authorization: Basic bmVvNGo6dmVyeXNlY3JldA==
Content-Type: application/json
{
"statement": "PROFILE MATCH (n:Person {name: $name}) RETURN n.name",
"parameters": {
"name": "Alice"
}
}
Example response
202: OK
Content-Type: application/json
{
"data": {
"fields": [
"n.name"
],
"values": [
"Alice"
]
},
"profiledQueryPlan": {
"dbHits": 0,
"records": 1,
"hasPageCacheStats": false,
"pageCacheHits": 0,
"pageCacheMisses": 0,
"pageCacheHitRatio": 0.0,
"time": 0,
"operatorType": "ProduceResults@neo4j",
"arguments": {
"GlobalMemory": 312,
"planner-impl": "IDP",
"Memory": 0,
"string-representation": "Planner COST\n\nRuntime PIPELINED\n\nRuntime version 5.18\n\nBatch size 128\n\n+------------------+----+---------------------------+----------------+------+---------+----------------+------------------------+-----------+---------------------+\n| Operator | Id | Details | Estimated Rows | Rows | DB Hits | Memory (Bytes) | Page Cache Hits/Misses | Time (ms) | Pipeline |\n+------------------+----+---------------------------+----------------+------+---------+----------------+------------------------+-----------+---------------------+\n| +ProduceResults | 0 | `n.name` | 1 | 1 | 0 | 0 | | | |\n| | +----+---------------------------+----------------+------+---------+----------------+ | | |\n| +Projection | 1 | cache[n.name] AS `n.name` | 1 | 1 | 0 | | | | |\n| | +----+---------------------------+----------------+------+---------+----------------+ | | |\n| +Filter | 2 | cache[n.name] = $name | 1 | 1 | 8 | | | | |\n| | +----+---------------------------+----------------+------+---------+----------------+ | | |\n| +NodeByLabelScan | 3 | n:Person | 10 | 4 | 5 | 248 | 3/0 | 0.453 | Fused in Pipeline 0 |\n+------------------+----+---------------------------+----------------+------+---------+----------------+------------------------+-----------+---------------------+\n\nTotal database accesses: 13, total allocated memory: 312\n",
"runtime": "PIPELINED",
"runtime-impl": "PIPELINED",
"DbHits": 0,
"batch-size": 128,
"Details": "`n.name`",
"planner-version": "5.18",
"PipelineInfo": "Fused in Pipeline 0",
"runtime-version": "5.18",
"Id": 0,
"EstimatedRows": 0.5,
"planner": "COST",
"Rows": 1
},
"identifiers": [
"n",
"`n.name`"
],
"children": [
{
"dbHits": 0,
"records": 1,
"hasPageCacheStats": false,
"pageCacheHits": 0,
"pageCacheMisses": 0,
"pageCacheHitRatio": 0.0,
"time": 0,
"operatorType": "Projection@neo4j",
"arguments": {
"Details": "cache[n.name] AS `n.name`",
"PipelineInfo": "Fused in Pipeline 0",
"Id": 1,
"EstimatedRows": 0.5,
"DbHits": 0,
"Rows": 1
},
"identifiers": [
"n",
"`n.name`"
],
"children": [
{
"dbHits": 8,
"records": 1,
"hasPageCacheStats": false,
"pageCacheHits": 0,
"pageCacheMisses": 0,
"pageCacheHitRatio": 0.0,
"time": 0,
"operatorType": "Filter@neo4j",
"arguments": {
"Details": "cache[n.name] = $name",
"PipelineInfo": "Fused in Pipeline 0",
"Id": 2,
"EstimatedRows": 0.5,
"DbHits": 8,
"Rows": 1
},
"identifiers": [
"n"
],
"children": [
{
"dbHits": 5,
"records": 4,
"hasPageCacheStats": true,
"pageCacheHits": 3,
"pageCacheMisses": 0,
"pageCacheHitRatio": 1.0,
"time": 453072,
"operatorType": "NodeByLabelScan@neo4j",
"arguments": {
"Details": "n:Person",
"PipelineInfo": "Fused in Pipeline 0",
"Memory": 248,
"Time": 453072,
"Id": 3,
"EstimatedRows": 10.0,
"PageCacheMisses": 0,
"DbHits": 5,
"Rows": 4,
"PageCacheHits": 3
},
"identifiers": [
"n"
],
"children": []
}
]
}
]
}
]
},
"bookmarks": [
"FB:kcwQ/wTfJf8rS1WY+GiIKXsCXgyQ"
]
}