General database role privilege handling in SQL Server

General database role privilege handling in SQL Server   Recently, we have been doing database privilege cleanup with colleagues, mainly by deleting some accounts, removing the larger privileges of some accounts, etc. For example, some have db_owner privileges, we remove the database role db_owner of the accounts and grant the minimum required ...

Added by Karpathos on Wed, 15 May 2019 18:59:55 +0300

Fabrication Process of Imitating 9GAG (V)

I have something to say: After completing the data display function, I want to improve the whole APP. It is found that the background is very chaotic, and there are many points that are not available. For example, the picture should have thumbnails and original pictures, paragraphs, comments and comments should be linked together, paragraphs sh ...

Added by gordo2dope on Wed, 15 May 2019 17:30:51 +0300

Python Reptilian Actual Warfare: Climbing the All-Station Novels List

As you all know, there are always some novel that is refreshing, whether it is fairy-man or fantasy. The first dozen chapters successfully circled a large wave of fans, successfully climbed the soaring list, hot list and other lists, throwing a few chestnuts out: As a developer, it is particularly important to have a lea ...

Added by eabigelow on Wed, 15 May 2019 12:37:31 +0300

PostgreSQL page inspect diagnoses and optimizes the query performance degradation caused by the delay of GIN (inverted) index merging

Label PostgreSQL, brin index, gin index, merge delay, gin_pending_list_limit, query performance degradation background GIN index is an inverted index of PostgreSQL database with multi-value type. A record may involve KEY in multiple GIN indexes. So if index is merged in real time when writing, IO will increase sharply and RT will increase in ...

Added by hatching on Wed, 15 May 2019 09:30:25 +0300

CDH Installation Documentation

1. Installation environment CentOS 6.8 Virtual Machine Three 1G per memory 50G per hard disk 2. Installation packages required CDH5.9.0 Installation Package Files included: Parcel contains files: Files included in rpms: Before you start the installation below, make sure the number of files is correct 3. Installation steps First, ...

Added by robman2100 on Wed, 15 May 2019 09:27:31 +0300

InnoDB Engine B+Tree Index Usage and New Features

We've already talked about it Principle and algorithm of MySQL InnoDB index Here's how to manage and use B+tree indexes and some new features. Management of B+Tree Index The basic indexes we use in the InnoDB engine are B+tree indexes. Create and delete indexes It can be created and deleted in two ways: # Mode 1: alter table, in which case bot ...

Added by ehhwan on Wed, 15 May 2019 05:12:03 +0300

mongodb installation and Application

1. Install the database If necessary, update the yum package management first. Take the CentOS system as an example below: $ yum -y update 1. Install Mongodb View the current system version $ cat /etc/redhat-release open https://repo.mongodb.org/yum/... , select the mongo version that suits your system, and then edit the Mongodb installation so ...

Added by Rianna on Wed, 15 May 2019 00:05:10 +0300

Introduction of AspNetCore Limit Middleware

IpRateLimitMiddleware(Github: AspNetCoreRateLimit ) is a stream-limiting middleware for ASPNETCore that controls how often clients invoke APIs. If clients frequently access the server, it can limit its frequency and reduce the pressure of accessing the server.Or if a crawler is crawling critical data, you can limit the number of ca ...

Added by dapuxter on Tue, 14 May 2019 20:08:52 +0300

PostgreSQL 11.1 trillion tpcb performance test on Aliyun ECS + ESSD + zfs/lvm2 strip + block_size=32K

Label PostgreSQL, pgbench, tpcb, tpcc, tpch, lvm2, zfs, bands background Several recent PostgreSQL OLTP and OLAP tests: PostgreSQL 11 tpcc Test (103,000 tpmC on ECS) - use sysbench-tpcc by Percona-Lab (TPC-H test SF=10,SF=200) PostgreSQL 11 vs 10 vs Deepgreen PostgreSQL 10 billion tpcb performance on ECS PostgreSQL on Aliyun ECS + ESSD - 100 ...

Added by stanleycwb on Tue, 14 May 2019 14:43:51 +0300

Nested Query of Cloud Functions in Small Programs

Just using cloud development, I don't know if there are nested query statements in the small program database, so I can only use the most clumsy method to find out the loop and look up again. Okay, next, the question is, have you found out, what kind of value you found? I've been working on this problem for a day. I just starte ...

Added by james_andrews on Tue, 14 May 2019 14:10:23 +0300