Month: December 2018

The MySQL database looks at the size and number of records occupied by the data table.

MySQLYou can open MySQL’s information_schema database if each table in the database takes up space and the number of rows it records. There is a TABLES table in the library. The main fields of the table are: TABLE_SCHEMA : Database nameTABLE_NAME: table nameENGINE: storage engine usedTABLES_ROWS: record numberDATA_LENGTH: data sizeINDEX_LENGTH: index size The size of the space occupied by a table is equivalent to the size of the data and the size of the index.Examples: 1、View all the table sizes of the enrolment_db Library: select table_name,table_rows from tables where TABLE_SCHEMA =...

Vue first experience

As a front-end rookie, in the usual development and learning, in addition to in-depth understanding of the various features of JavaScript and css, familiar with a framework is also essential. Vue is very popular because of its small, lightweight, learning and smoothing features. Here is a summary of the pit and tricks of the little rookie. 1.Avoid double brackets when loading pages. Official recommendation v-cloak <style>   [v-cloak] { display: none; } </style> <div id=’app’ v-cloak> {{message}} </div> 2.I haven’t thought about it yet

Kafka performance test 1.0.0

kafkaProvide tool kafka-producer-perf-test.sh for pressure measurement. parameter Explain messages                Producers send the total number of messages. message-size Size of each message batch-size Number of messages sent per batch topics Topic sent by producer threads Producers use several threads to send simultaneously. broker-list  List of machine ip:port for installing Kafka services producer-num-retries A message failed to send retry times. request-timeout-ms A message request sends timeout time.   ./kafka-produce...

Bzoj3993: [SDOI2015] interstellar warfare (two points + maximum flow)

Title Description 3333In the year of the galaxy, the X corps and the Y regiment are fighting fiercely. At one stage of the battle, Legion Y dispatched a total of N giant robots to attack Legion X positions, of which the armor value of the first giant robot was Ai. When the armor value of a giant robot is reduced to zero or less, the giant robot is destroyed. XThe Legion has M laser weapons, the second of which can reduce the armor value of a giant robot Bi per second. The attack of laser weapons is continuous. This laser weapon is very strange. A laser weapon can only attack certain enemies. ...

Selenium+python automation — file download pop-up processing (PyKeyboard)

selenium+pythonAutomatic 99– file download pop-up processing (PyKeyboard) Original: Shanghai leisurely Learning automation test from scratch Learning automation test from scratch Wechat number yoyoketang Functional introduction This public number is dedicated to automated testing and will continue to update automation tutorials covering selenium, appium, python, interface automation, robot framework, jmeter, fiddler, etc. this Preface In the web automation download operation, sometimes pop-up download box, this kind of download box does not belong to the web page, is unabl...

[Codeforces 1016F]Road Projects

Description Topic library link Give you a tree\(n\) Tree of nodes\(1\) reach\(n\) The cost is\(1\) reach\(n\) The length of the shortest path between nodes. Now give it to you\(m\) The group asks you to add an edge weight.\(w\) The maximum value of the cost is not the same as the original graph. Questioning is independent of each other. \(1\leq n,m\leq 3\times 10^5\) Solution Spicy chicken, Lao Yu destroys my youth. hold\(1\) to\(n\) When the path is extracted, it is obvious that the graph becomes a chain plus some subtrees. Greedy thinking is to find such a group of points to meet. Its subt...