Use guide for Foreign Data Wrappers of PostgreSQL

The function of PostgreSQL's fdw implementation is the cross database operation between each PostgreSQL database and the remote database. The function is the same as oracle's dblink. The environment in this article is shown below: 1.1. Target installation software package [root@hdp06 ~]# yum -y install postgresql10-contrib.x86_64 1.2 creating ...

Posted by introvert on Sat, 07 Dec 2019 14:14:23 -0800

PostgreSQL spatial aggregation performance - administrative area, electronic fence spatial aggregation - time, space thermal map

Label PostgreSQL, spatial aggregation, spatial heat map, administrative region, electronic fence background For a certain time interval (or other conditions), how many objects (space point information) appear in some fences and administrative areas (polygon information), and render these polygons by color depth. for example Example 1. Are ...

Posted by ZephyrWest on Thu, 21 Nov 2019 14:12:51 -0800

PostgreSQL pipelinedb flow calculation plug-in - IoT application - real time trajectory aggregation

Label PostgreSQL, IOT, track aggregation, pipelinedb, flow calculation, real-time aggregation background IoT scenes, Internet of vehicles scenes, shared bicycle scenes, human behavior sites, etc. the terminal reports isolated sites in real time. We need to supplement them into tracks. For example, sharing bicycles, placing orders, unlocking, ...

Posted by haku87 on Thu, 21 Nov 2019 10:23:50 -0800

The solution of using mybatis and PostgreSQL Json fields as query criteria

Date:2019-11-15 Think before reading: You didn't think of a solution? Is PostgreSQL database supported by itself or is there another solution?   Note: first of all, the reason why the database uses the Json data type is that when we do an app push business, the backend pushes several fields to the app We use jsonb data type directly here. Using ...

Posted by thelinx on Fri, 15 Nov 2019 11:12:40 -0800

PosgreSQL master-slave replication

1. Introduction Posgres introduced a master-slave stream replication mechanism after 9.0. Stream replication refers to synchronizing the corresponding data from the master server through the tcp stream from the server.This allows backups to be made from the server when the primary server data is lost.Stream replication allows updates to be mai ...

Posted by sarika on Sat, 09 Nov 2019 09:34:43 -0800

Gausdb 200 uses GDS to import data from a remote server

Gausdb 200 supports importing data in TEXT, CSV and FIXED formats that exist on the remote server into the cluster. This article introduces the use of GDS (Gauss Data Service) tools to import data from remote servers into GaussDB 200. The environment is as follows: 1. Prepare source data Here, from the PostgreSQL database, use the copy command ...

Posted by phppssh on Sun, 03 Nov 2019 23:13:09 -0800

Advanced sharing in iOS development - new framework in iOS 13 - MetriKit

MetriKit is a new framework for collecting and processing batteries and performance metrics in iOS 13. This is WWDC working with XCTestMetrics and Xcode Metrics organizers this year as part of a concerted effort to bring new insights to developers about the performance of their applications in this area. Apple will automatically collect Metr ...

Posted by wilsonodk on Wed, 23 Oct 2019 23:44:18 -0700

Settings of Self-Increasing Fields in Databases (MySQL, PostgreSQL, Oracle, MsSQL)

In the process of database design, we usually set the ID field in the database table to increase by itself. Following is an example of a commonly used data dictionary table to illustrate how to set up self-increasing fields in each database. MySQL The MySQL database only needs to add AUTO_INCREMENT to the target field and set AUTO_INCREMENT=x f ...

Posted by robertaccettura on Wed, 02 Oct 2019 00:56:01 -0700

Coordinate Conversion, EPSG:4326 Conversion to Golden Coordinate Course

Here we first introduce several coordinate systems: 1.WGS84: International coordinate system, a geodetic coordinate system, is also the coordinate system widely used in GPS Global Satellite Positioning System.2.GCJ02: Mars coordinate system is a coordinate system of Geographic Information System formulated by the State Bureau of Surveying and ...

Posted by phaseonemedia on Tue, 17 Sep 2019 01:40:48 -0700

PostgreSQL 12: Recovery.conf file parameters merged into postgresql.conf

An important change in PostgreSQL 12 is that the parameters in the recovery.conf configuration file are merged into postgresql.conf and recovery.conf is no longer in use. Let's look at the instructions in the manual as follows: Release Notes Move recovery.conf settings into postgresql.conf (Fujii Masao, Simon Riggs, Abhijit Menon-Sen, Sergei K ...

Posted by RealDrift on Tue, 20 Aug 2019 19:46:22 -0700