pandas is a third-party library that must be familiar with for data analysts. pandas has great advantages in scientific computing, especially for data analysts. There is Numpy in python, but Numpy is more mathematic. There is also a need for a database to represent the data model more specifically. We are very clear that EXCEL plays a very impo ...
Posted by jthomp7 on Wed, 15 May 2019 20:33:13 +0200
1.1 character set
Character Set: A set of binary codes for visible characters when they are saved and transmitted.
Character sets are used in two places
1. Save data
2. Data transmission
1.2 Use Character Sets for Survival
1. MySQL can specify character encoding on servers, databases, tables a ...
Posted by Greaser9780 on Wed, 15 May 2019 19:48:27 +0200
Algorithms Series 15 Days Quick - Fifth Date Five Classic Search
Do you know that in fact, there is an O(1) search, the so-called second kill.
Yeah, he's hash lookup. When it comes to hash, you must mention hash functions. Ha-ha, this thing has already formed in ...
Posted by atl_andy on Wed, 15 May 2019 18:49:17 +0200
1. Enter the mysql command line, enter root and password
[root@localhost ~]# mysql -u root -p
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 19
Server version: 5.7.22 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
Posted by hyp0r on Wed, 15 May 2019 14:21:26 +0200
Generate certificates for WEB servers with openssl (self-signed CA certificates, server certificates)
Source: https://www.cnblogs.com/osnosn/p/10608455.html Come from osnosn's blog
Written in: 2019-03-28.
Do not want to use self-signed certificate, want to apply for a free server certificate online, see this article: Apply for Freessl Server C ...
Posted by rid243 on Wed, 15 May 2019 13:31:28 +0200
Checking of Check Agreement
I found that in the last article I forgot to check my agreement. Although there is no agreement, it still needs to be done.
Find the corresponding area in register.html:
<input type="checkbox" name="aggree" value="1"> I agree to the agreement ...
PostgreSQL, imgsmlr, GiST, image eigenvalues, wavelet transform
"PostgreSQL 11 Similar Image Search Plug-in imgsmlr Performance Test 1 - Single Table (400 million images)"
Parallel invocation using partition table + dblink asynchronous interface. (It's better to support imgsmlr gist index scan directly at ...
Posted by synapp2 on Wed, 15 May 2019 10:27:10 +0200
Three servers 192.168.1.40/41/42
Installation package mongodb-linux-x86_64-amazon 2-4.0.1.tgz
Shard server 1 master node
Shard server 1 secondary node
Shard server 1 arbitration
Shard server 2 arbitration
Shard server 2 ...
Posted by ja_blackburn on Wed, 15 May 2019 03:03:21 +0200
I. Main features of MySQL 5.7
(1) Native Support Systemd
(2) Better performance: for multi-core CPU, solid-state hard disk, lock has better optimization
(3) Better InnoDB storage engine
(4) More robust replication: replication brings a solution that data is not lost at all. Traditional financial customers can also use mysql database.
(5) A ...
Posted by mcubedma on Tue, 14 May 2019 23:09:50 +0200
PostgreSQL is an open source object relational database management system (ORDBMS). This paper aims to introduce some basic operations of PostgreSQL (hereinafter referred to as pg) for beginners'reference and reference. It should be noted that all the following operations were performed in Ubuntu 16.04, using version 9.6 of PG. For diff ...
Posted by may27 on Tue, 14 May 2019 20:20:13 +0200