SequoiaDB giant sequoia database-detailed access plan on data nodes

The detailed access plan on the data node includes the following:

• Access plan information on the data node
• Cache usage of access plan
• Access plan information of the main and child tables in the vertical partition involved

Detailed access plan for the main table

The detailed access plan structure of the main table is as follows:

{
  { 主表的访问计划信息 },
  "PlanPath": {
    "Operator": "MERGE",
    { 主表查询上下文的访问计划信息 },
    "ChildOperators": [
      {
        { 子表的访问计划信息 },
        ...
      },
      ...
    ]
  }
}

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The main table access plan includes the following information:

Field name	Types of	description
NodeName	String	The name of the node where the access plan is located
GroupName	String	The name of the replication group to which the node where the access plan belongs
Role	String	The role of the node where the access plan is located, "data" represents the coordination node
Collection	String	The name of the collection accessed by the access plan
Query	BSON object	User query conditions after access plan analysis
Sort	BSON object	Sort field in access plan
Selector	BSON object	Access plan execution selector
Hint	BSON object	The specified query in the access plan uses the index
Skip	Long integer	The number of records to be skipped in the access plan
Return	Long integer	The maximum number of records returned by the access plan
Flag	Integer	The execution flag specified in the access plan, the default value is 0
ReturnNum	Long integer	The number of records returned by the access plan
ElapsedTime	Floating point	Access plan query time (unit: second)
IndexRead	Long integer	The number of index records scanned by the access plan
DataRead	Long integer	Number of scan data records of access plan
UserCPU	Floating point	Access plan user mode CPU usage time (unit: second)
SysCPU	Floating point	Access plan kernel mode CPU usage time (unit: second)
PlanPath	BSON object	The specific execution of the access plan MERGE

Note:

MERGE contains the access plan of the child table, that is, the access plan of the ordinary collection on the data node

Example:

{
  "NodeName": "hostname:11820",
  "GroupName": "group",
  "Role": "data",
  "Collection": "maincs.maincl",
  "Query": {},
  "Sort": {
    "a": 1
  },
  "Selector": {},
  "Hint": {},
  "Skip": 0,
  "Return": -1,
  "Flag": 2048,
  "ReturnNum": 50000,
  "ElapsedTime": 1.225226,
  "IndexRead": 0,
  "DataRead": 50000,
  "UserCPU": 0.5399999999999991,
  "SysCPU": 0.02000000000000002,
  "PlanPath": {
    "Operator": "MERGE",
    ...
  }
}

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Detailed access plan for general collection or sub-table

The detailed access plan structure of a common set or sub-table is as follows:

{
  { 集合的访问计划信息 },
  "PlanPath": {
    { 查询上下文的访问计划信息 }
    ...
  }
}

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The visit plan includes the following information:

Field name	Types of	description
NodeName	String	The name of the node where the access plan is located
GroupName	String	The name of the replication group to which the node where the access plan belongs
Role	String	The role of the node where the access plan is located, "data" means the data node
Collection	String	The name of the collection accessed by the access plan
Query	BSON object	User query conditions after access plan analysis
Sort	BSON object	Sort field in access plan
Selector	BSON object	Access plan execution selector
Hint	BSON object	The specified query in the access plan uses the index
Skip	Long integer	The number of records to be skipped in the access plan
Return	Long integer	The maximum number of records returned by the access plan
Flag	Integer	The execution flag specified in the access plan, the default value is 0
ReturnNum	Long integer	The number of records returned by the access plan
ElapsedTime	Floating point	Access plan query time (unit: second)
IndexRead	Long integer	The number of index records scanned by the access plan
DataRead	Long integer	Number of scan data records of access plan
UserCPU	Floating point	Access plan user mode CPU usage time (unit: second)
SysCPU	Floating point	Access plan kernel mode CPU usage time (unit: second)
CacheStatus	String	Cache status of the access plan: 1. "NoCache" is not added to the cache 2. "NewCache" is the newly created cache 3. "HitCache" is the hit cache
MainCLPlan	Boolean	Whether the access plan is a query plan shared by the main table
CacheLevel	String	访问计划的缓存级别：1. "OPT_PLAN_NOCACHE" 为不进行缓存 2. "OPT_PLAN_ORIGINAL" 为缓存原查询计划 3. "OPT_PLAN_NORMALZIED" 为缓存泛化后的查询计划 4. "OPT_PLAN_PARAMETERIZED" 为缓存参数化的查询计划，"OPT_PLAN_FUZZYOPTR" 为缓存参数化并带操作符模糊匹配的查询计划
Parameters	数组类型	参数化的访问计划使用的参数列表
MatchConfig	BSON 对象	访问计划中的匹配符的配置
MatchConfig.EnableMixCmp	布尔型	访问计划的匹配符是否使用混合匹配模式
MatchConfig.Parameterized	布尔型	访问计划的匹配符是否支持参数化
MatchConfig.FuzzyOptr	布尔型	访问计划的匹配符是否支持模糊匹配
PlanPath	BSON 对象	访问计划的具体执行操作 SORT、TBSCAN 或 IXSCAN
Search	BSON 对象	查询计划优化器搜索过的访问计划 Search 选项为 true 时显示 请参考基于代价的访问计划评估

Note:

数据节点上的主表的访问计划请参考主表的访问计划

示例：

{
  "NodeName": "hostname:11820",
  "GroupName": "group",
  "Role": "data",
  "Collection": "sample.employee",
  "Query": {
    "a": {
      "$gt": 100
    }
  },
  "Sort": {},
  "Selector": {},
  "Hint": {},
  "Skip": 0,
  "Return": -1,
  "Flag": 2048,
  "ReturnNum": 0,
  "ElapsedTime": 0.000093,
  "IndexRead": 0,
  "DataRead": 0,
  "UserCPU": 0,
  "SysCPU": 0,
  "CacheStatus": "HitCache",
  "MainCLPlan": false,
  "CacheLevel": "OPT_PLAN_PARAMETERIZED",
  "Parameters": [
    100
  ],
  "MatchConfig": {
    "EnableMixCmp": false,
    "Parameterized": true,
    "FuzzyOptr": false
  },
  "PlanPath": {
    ...
  }

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