com.mongodb

枚举 ExplainVerbosity

java.lang.Object

java.lang.Enum<ExplainVerbosity>

com.mongodb.ExplainVerbosity

所有已实现的接口:

java.io.Serializable, java.lang.Comparable<ExplainVerbosity>

public enum ExplainVerbosity
extends java.lang.Enum<ExplainVerbosity>

An enumeration of the verbosity levels available for explaining query execution.

从以下版本开始:

3.0

Since server release

3.0

枚举常量概要

枚举常量

枚举常量和说明
ALL_PLANS_EXECUTIONS Runs the query optimizer and chooses the winning plan, but then runs all generated plans to completion.
EXECUTION_STATS Runs the query optimizer, and then runs the winning plan to completion.
QUERY_PLANNER Runs the query planner and chooses the winning plan, but does not actually execute it.

方法概要

限定符和类型	方法和说明
static ExplainVerbosity	valueOf(java.lang.String name) 返回带有指定名称的该类型的枚举常量。
static ExplainVerbosity[]	values() 按照声明该枚举类型的常量的顺序, 返回 包含这些常量的数组。

从类继承的方法 java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

从类继承的方法 java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

枚举常量详细资料

QUERY_PLANNER

public static final ExplainVerbosity QUERY_PLANNER

Runs the query planner and chooses the winning plan, but does not actually execute it. The use case for this verbosity level is "Which plan will MongoDB choose to run my query."

EXECUTION_STATS

public static final ExplainVerbosity EXECUTION_STATS

Runs the query optimizer, and then runs the winning plan to completion. In addition to the planner information, this makes execution stats available. The use case for this verbosity level is "Is my query performing well."

ALL_PLANS_EXECUTIONS

public static final ExplainVerbosity ALL_PLANS_EXECUTIONS

Runs the query optimizer and chooses the winning plan, but then runs all generated plans to completion. This makes execution stats available for all of the query plans. The use case for this verbosity level is "I have a problem with this query, and I want as much information as possible in order to diagnose why it might be slow."

方法详细资料

values

public static ExplainVerbosity[] values()

按照声明该枚举类型的常量的顺序, 返回 包含这些常量的数组。该方法可用于迭代 常量, 如下所示:

for (ExplainVerbosity c : ExplainVerbosity.values())
    System.out.println(c);

返回:

按照声明该枚举类型的常量的顺序返回的包含这些常量的数组

valueOf

public static ExplainVerbosity valueOf(java.lang.String name)

返回带有指定名称的该类型的枚举常量。 字符串必须与用于声明该类型的枚举常量的 标识符完全匹配。(不允许有多余 的空格字符。)

参数:

name - 要返回的枚举常量的名称。

返回:

返回带有指定名称的枚举常量

抛出:

java.lang.IllegalArgumentException - 如果该枚举类型没有带有指定名称的常量

java.lang.NullPointerException - 如果参数为空值