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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 ...

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 ...

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, ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...