PromQL Example - http requests total https://youtu.be/STVMGrYIlfg?t=417

https://youtu.be/STVMGrYIlfg?t=165

Prometheus Architecture

https://youtu.be/STVMGrYIlfg?t=55

The Prometheus time series are streams of timestamped values belonging to the same metric and the same set of labeled dimensions. Prometheus stores all data as time series.

A sample is a single value at a point in time in a time series.

In Prometheus, each sample consists of a float64 value and a millisecond-precision timestamp.

在Java中，异常分为两大类：checked exception（受检异常）和unchecked exception（非受检异常）。受检异常是那些在编译时期就必须处理的异常，否则程序无法编译通过。这种机制确保了开发者能够提前考虑到各种异常情况，并强制要求处理这些可能发生的异常，以增强程序的健壮性。

以下是一些常见的checked exception的例子：

1. IOException - 这是处理输入输出操作时可能遇到的异常，比如读写文件时。如果文件不存在，或者没有读写权限，就会抛出这个异常。

```java import java.io.BufferedReader; import java.io.FileReader; import java.io.IOException;

public class Main { public static void main(String[] args) { try { BufferedReader reader = new BufferedReader(new FileReader("somefile.txt")); String line; while ((line = reader.readLine()) != null) { System.out.println(line); } reader.close(); } catch (IOException e) { e.printStackTrace(); } } } ```

1. SQLException - 在处理数据库操作时，如果SQL查询有问题，或者连接数据库时遇到问题，就会抛出这个异常。

```java import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException;

public class DBConnect { public static void main(String[] args) { try { Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb", "user", "password"); // 使用连接对象进行数据库操作 } catch (SQLException e) { e.printStackTrace(); } } } ```

1. ClassNotFoundException - 这个异常发生在尝试加载类时，但找不到该类。这经常发生在使用Class.forName()动态加载类时。

java public class Main { public static void main(String[] args) { try { Class.forName("com.mysql.jdbc.Driver"); } catch (ClassNotFoundException e) { e.printStackTrace(); } } }

这些checked exception必须被显式地捕获（try-catch）或者在方法签名中通过throws子句声明。这样做的目的是提醒开发者，这些操作可能会失败，并且需要有相应的处理逻辑来应对这些失败的情况。

Linux Kernel, Librarian Analogy

The benefit of creating such a massive key word in context index for the Wörterbuch der ägyptischen Sprache meant that instead of using an ad hoc translation method (guessing based on limited non-cultural context) for a language, which was passingly familiar, but not their mother tongue, Adolph Erman and others could consult a multitude of contexts for individual words and their various forms to provide more global context for better translations.

Other dictionaries like the Oxford English Dictionary attempt to help do this as well as provide the semantic shift of words over time because the examples used in creating the dictionary include historical examples from various contexts.

Richards, Olly. Interview with Michel Thomas Publisher Sue Hart, 2017. https://www.youtube.com/watch?v=abjrsATBc5A.

Thomas had a secretive nature and did most communication either over phone or in person. He didn't write letters. Sue Hart felt that it was the result of his experience in World War II. (Potentially relationship with spycraft?)

He was a bit of a showman and enjoyed dropping names. He enjoyed his fame and status. Thomas seemed to enjoy people listening to him and didn't appreciate confrontation and dealt with it by shutting people off and walking away.

Nothing deep here about his method really. All just background.

https://www.youtube.com/watch?v=abjrsATBc5A