Interview series - 4 hash application scenario analysis and Practice
British Fleming once said: "don't wait for luck, you should try to master knowledge."
1 Preface
Hello, I'm amu! Your harvest is my love, and your praise is my recognition.
As a graduate with one-year development experience, we talked with the interviewer about the list type of basic data structure of redis in the previous chapter. ...
Added by gaza165 on Sat, 19 Feb 2022 01:05:56 +0200
linux: thread POSIX semaphore & & thread pool
POSIX semaphore
POSIX semaphores and SystemV semaphores have the same function. They are used for synchronous operation to achieve the purpose of accessing shared resources without conflict. However, POSIX can be used for inter thread synchronization.
1. System call function of POSIX semaphore
Header file: #include < semaphore h>
...
Added by Brian Swan on Sat, 19 Feb 2022 01:03:53 +0200
Promise constructor method
What is Promise 1. Know Promise: Promise is a solution for asynchronous operation. Let's talk about asynchronous first: The callback function is actually an asynchronous operation, for example:
document.addEventListener(
'click',
() => {
console.log('This is asynchronous');
},
false
);
...
Added by tieded on Sat, 19 Feb 2022 01:01:32 +0200
[data structure from bronze to king] Part 4: queue of data structure
Catalogue of series articles
preface
1, Concept and structure of queue
1. Concept of queue
Queue: a special linear table that only allows inserting data at one end and deleting data at the other end. The queue has a first in first out FIFO(First In First Out) into the queue: the end of the queue where the inserting operation i ...
Added by PoOP on Sat, 19 Feb 2022 00:57:44 +0200
SSM - aop idea - three ways to implement aop (interface, customization, annotation)
preface
In the software industry, AOP is the abbreviation of Aspect Oriented Programming, which means: Aspect Oriented Programming, a technology that realizes the unified maintenance of program functions through precompiled mode and dynamic agent during operation. AOP is the continuation of OOP, a hot spot in software development, an impor ...
Added by iceblox on Sat, 19 Feb 2022 00:49:58 +0200
Pandas analyzes the preference of American name selection
1. Pre competition preparation
1.1 Preface
Sponsored by open source learning organization Datawhale, this event mainly leads learners to use Python for data analysis and data visualization, including four parts: data set processing, data exploration and clarity, data analysis and data visualization, using pandas, matplotlib Third party librar ...
Added by twinedev on Sat, 19 Feb 2022 00:45:32 +0200
impala series: Service API--select
Basic grammar
[WITH name AS (select_expression) [, ...] ]
SELECT
[ALL | DISTINCT]
[STRAIGHT_JOIN]
expression [, expression ...]
FROM table_reference [, table_reference ...]
[[FULL | [LEFT | RIGHT] INNER | [LEFT | RIGHT] OUTER | [LEFT | RIGHT] SEMI | [LEFT | RIGHT] ANTI | CROSS]
JOIN table_reference
[ON join_equality_clauses | USING ( ...
Added by CrashRoX on Sat, 19 Feb 2022 00:44:52 +0200
Deep understanding of Promise, the core of JS asynchronous programming
In fact, before the emergence of ES6 standard, the community first put forward the Promise scheme. Later, with the addition of ES6, its usage was unified and native Promise objects were provided.
Promise basic information
If you have to explain what Promise is, it is simply a container that holds the results of an event (usually asynchronou ...
Added by storyboo on Sat, 19 Feb 2022 00:41:09 +0200
Learn Java--day04--Process Control Statement &Method from scratch
Learn Java - day04 - Process Control Statements from scratch (2) & Methods
1. Process control statements
1. Dead cycle
Dead Loop: A loop that cannot be terminated by self-control in a program Classification: Dead loop of for statement
for ( ; ; ) {
Loop body statement;
}
Dead loop of while statement
while (true) {
Loop body ...
Added by r3dn3ck on Sat, 19 Feb 2022 00:39:46 +0200
Java JDBC programming North
preface
In our daily APP or website, we often need to access data. For example, in wechat, we need to store a series of information such as our user name, mobile phone number, user password, etc. Relying on the Java related knowledge learned before can no longer meet this demand. Now the most basic and widely used application program is relati ...
Added by icey37 on Sat, 19 Feb 2022 00:35:57 +0200