pgRouting路径规划数据准备

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PostgreSQL中的空间查询与地理信息系统(GIS)

PostgreSQL中的空间查询与地理信息系统（GIS）PostgreSQL是一种可扩展的关系型数据库管理系统，具有广泛的功能和灵活性，其中包含了强大的地理信息系统（GIS）功能。

GIS是一种用于存储、管理和分析地理空间数据的系统。

本文将介绍PostgreSQL中的空间查询和GIS功能，探讨如何利用这些功能进行地理信息的处理和分析。

一、空间数据类型在PostgreSQL中，空间数据类型是通过PostGIS插件来实现的。

PostGIS是一个在PostgreSQL上构建GIS应用程序的开源空间数据库扩展。

它为地理空间数据提供了存储、查询和分析的功能。

常用的空间数据类型包括点(Point)、线(Line)、多边形(Polygon)和多点(MultiPoint)等。

二、空间查询在进行空间查询之前，需要在数据库中创建空间索引，以提高查询效率。

通过创建空间索引，可以加快对空间数据的访问和查询速度。

在PostgreSQL中，使用CREATE INDEX语句来创建空间索引，指定空间索引类型为GIST或者SP-GIST。

1. 空间属性查询空间属性查询主要用于查询空间数据的属性信息。

常见的空间属性查询包括获取点的坐标信息、计算线的长度、计算面积等。

例如，可以使用ST_AsText函数将空间数据类型转换为文本形式，以便查看点的坐标信息。

2. 空间关系查询空间关系查询用于判断空间数据之间的关系，例如判断两个多边形是否相交、包含关系等。

PostgreSQL提供了一系列的空间关系查询函数，如ST_Contains、ST_Intersects等。

这些函数可以用于判断两个空间数据之间的关系并返回相应的结果。

3. 空间分析查询空间分析查询用于对空间数据进行分析和处理。

例如，可以使用ST_Buffer函数对点进行缓冲区分析，生成以某个点为中心的缓冲区区域。

还可以使用ST_Intersection函数计算两个多边形的交集，以获得共同的区域。

eigrp协议最佳路径

eigrp协议最佳路径全文共四篇示例，供读者参考第一篇示例：EIGRP（Enhanced Interior Gateway Routing Protocol）是一种常用的路由协议，用于在网络中找到最佳路径以进行数据传输。

EIGRP 使用了DUAL（Diffusing Update Algorithm）算法来计算最佳路径，并可以快速适应网络拓扑变化。

在网络中，数据包传输的效率和稳定性取决于选择的最佳路径，因此了解和优化EIGRP协议最佳路径是网络优化的重要一环。

EIGRP协议最佳路径的选择是根据路由器维护的路由表信息和拓扑数据库来进行的。

路由表中保存了到达目的网络的各个路径，以及每条路径的开销信息。

路径的开销由一系列因素组成，包括带宽、延迟、可靠性等指标。

EIGRP通过比较这些参数来选择最佳路径。

在EIGRP中，每个路由器都会维护一个拓扑数据库，记录了网络拓扑结构和路由信息的更新。

当网络拓扑发生变化时，路由器会向周围的邻居发送更新信息，以便更新最佳路径的选择。

在选择最佳路径时，EIGRP还考虑了路径的可靠性和负载情况。

可靠性是指路径的稳定性和故障恢复能力，EIGRP会选择具有较高可靠性的路径作为最佳路径。

负载指的是路径的负载情况，EIGRP会尽量避免选择负载较高的路径，以保证数据包传输的效率。

优化EIGRP协议最佳路径可以通过以下几个方面进行：1. 调整带宽和延迟参数：带宽和延迟是EIGRP选择最佳路径的关键参数，通过调整这些参数可以影响路径选择的结果。

提高优先级的路径会成为EIGRP协议所选择的最佳路径。

2. 去除不必要的路径：在网络中可能存在一些冗余的路径，这些路径在数据传输中并没有起到作用，只会增加网络的负载和复杂度。

去除这些不必要的路径可以优化EIGRP协议的最佳路径选择。

3. 使用路由汇总：路由汇总是将多个子网的路由信息合并成一个汇总路由信息，可以减少路由表的条目，简化路径选择过程，提高网络性能。

基于Leaflet的校园电子地图的设计与实现

2 系统框架设计
校园电子地图系统采用 B / S 架构模式，分为数据层、服务层和应用层，具体结构如图 1 所示。
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PostgreSQL PostGIS
图 1 系统总体架构
2021 年 1 月第 19 卷第 1 期
doi:10. 3969 / j. issn.1672 - 4623.2021.01.016
地理空间信息
GEOSPATIAL INFORMATION
Jan. , 2021 Vol.19, No.1
基于 Leaflet 的校园电子地图的设计与实现
赵建伟 1，季民 1
统。研究了从地图存储到渲染与服务发布，再到基于 Leaﬂet 进行功能开发的全过程，验证了该方法的可行性。
关键词：Leaﬂet；校园电子地图；开源 GIS；GeoServer
中图分类号：P208
文献标志码：B
文章编号：1672-4623（2021）01-0061-04
我国拥有 2 900 余所高等学校，校园面积大、建筑多是其显著特点，然而商业地图对校园的展示不够全面，因此开发校园电子地图是改善这种状况行之有效的途径。校园电子地图针对老师、同学的需求提供相关校园信息，相较于其他电子地图拥有自己的特征。校园电子地图以先进的科学技术为载体，以互联网为传播媒介，将校园环境作为指定领域，最大程度地还原真实的校园。
进行最短路径求解时，其计算节点数量比 Dijkstra 算

OSGeo：开源GIS软件、在线教程、数据相关资料

OSGeo中国中心：开源GIS软件、在线教程、数据相关资料桌面GIS
用于桌面电脑环境的GIS 信息浏览、编辑和分析工具
网页GIS（Browser Facing GIS）
用于浏览器环境的GIS 信息浏览、编辑和分析工具
网络服务
空间信息的网络发布
数据库
空间数据库系统
地图与导航
空间工具
空间信息分析系统
专门领域GIS 系统
特定GIS 应用领域的专业工具
数据
地理空间数据集
地理空间操作函数库
其它相关软件（未包含在Live 系统）微软Windows 环境专有：
以往OSGeo-Live 版本包含的：
文档创作与翻译
OSGeo Live 文档是由OSGeo 社区成员和各个软件项目的开发团队共同完成的。

非英语版本来自于Live 翻译团队。

中文版本主要由以下成员翻译（排序按加入时间）：。

BGP多路径选择策略优化方法

BGP多路径选择策略优化方法BGP（Border Gateway Protocol）是互联网主干路由器之间通信的协议，它负责路由选择和路由传递。

在BGP中，多路径选择策略是一种重要的技术，可以实现负载均衡和故障容错。

本文将介绍一些BGP多路径选择策略的优化方法，旨在改善网络性能和增强路由的稳定性。

一、触发条件控制BGP多路径选择策略中，可以通过控制触发条件来优化路径选择。

默认情况下，BGP仅在当前的最佳路径发生故障时才会选择备用路径。

然而，网络管理员可以通过修改参数来调整触发条件。

例如，可以设置BGP在主路径的通信质量下降到一定程度时即启用备用路径。

这样可以避免在主路径完全中断之前出现延迟或丢包的问题。

二、路径属性加权路径属性加权是对BGP多路径选择策略进行优化的另一种方法。

在BGP中，路径属性是用于描述和评估路径的特性和性能的。

通过为路径属性分配权重，可以对路径进行排序和选择。

例如，可以根据带宽、延迟、可靠性等指标给路径属性进行权重设置，以便选择性能较好的路径。

三、基于地址的路径选择基于地址的路径选择是一种常用的BGP多路径选择策略优化方法。

在这种方法中，根据通信流量的源地址和目的地址选择路径。

例如，可以设置源地址基础的路径选择，将特定流量通过具有较低延迟的路径转发。

同时，也可以设置目的地址基础的路径选择，将流量转发到最近的目标网络。

四、流量分割和负载均衡流量分割和负载均衡是一种将网络流量分发到多个路径上的BGP优化方法。

通过将流量分割成多个较小的流量，并通过多个路径进行传输，可以实现负载均衡。

这种方法可以提高网络的吞吐量和性能。

同时，还可以通过设置不同路径的优先级，将关键数据流量优先传输，以确保网络的稳定性和可靠性。

五、状态监测和快速切换状态监测和快速切换是提高BGP多路径选择策略效率的关键方法之一。

通过对路径的状态进行实时监测和检测，可以在故障发生时快速切换到备用路径。

这种方法可以减少故障对网络的影响，并提高网络的可用性和恢复能力。

PostGISpgrouting路径分析

PostGISpgrouting路径分析--让数据库⽀持PostGIS和pgRouting的函数和基础表（安装后第⼀次使⽤时执⾏，以后都不再执⾏）CREATE EXTENSION postgis;CREATE EXTENSION pgrouting;CREATE EXTENSION postgis_topology;CREATE EXTENSION fuzzystrmatch;CREATE EXTENSION postgis_tiger_geocoder;CREATE EXTENSION address_standardizer;--注：使⽤postgis shapefile mport/export manager上传shp时，在Option中勾选“generate simple geometries instead of multi geometries”，以⽣成单个geometry -------------------------------------------以节点为参数进⾏最短路径分析--以road表作为实例-------------------------------------------ALTER TABLE road ADD COLUMN source integer;--起点ALTER TABLE road ADD COLUMN target integer;--终点ALTER TABLE road ADD COLUMN length double precision;--增加路线长度字段（根据长度设置权重）UPDATE road SET length = ST_Length(geom);--计算路线长度select pgr_createTopology('road', 0.0001, 'geom', 'gid');--创建拓扑SELECT*FROM pgr_dijkstra('SELECT gid as id,source::integer,target::integer,length::double precision as costFROM road',30, 60, false, false); --路径分析SELECT st_astext(geom) FROM pgr_dijkstra('SELECT gid AS id,source::integer,target::integer,length::double precision AS cost FROM road',30, 60, false, false) as dijoin road pt on di.id2 = pt.gid;--查询所经过的所有点SELECT seq, id1 AS node, id2 AS edge, cost,geom into dijkstra_res FROM pgr_dijkstra('SELECT gid AS id,source::integer,target::integer,length::double precision AS cost FROM road',30, 60, false, false) as di join road pt on di.id2 = pt.gid;--查询结果存储到新的表格select*from dijkstra_res;--查询表格内容-------------------------------------------以起始点坐标为参数进⾏最短路径分析--以gyroad表作为实例-------------------------------------------ALTER TABLE gyroad ADD COLUMN source integer;--起点ALTER TABLE gyroad ADD COLUMN target integer;--终点ALTER TABLE gyroad ADD COLUMN length double precision;--增加路线长度字段（根据长度设置权重）UPDATE gyroad SET length = ST_Length(geom);--计算路线长度select pgr_createTopology('gyroad', 0.0001, 'geom', 'gid');--创建拓扑--添加起始点坐标x,y字段ALTER TABLE gyroad ADD COLUMN x1 double precision;ALTER TABLE gyroad ADD COLUMN y1 double precision;ALTER TABLE gyroad ADD COLUMN x2 double precision;ALTER TABLE gyroad ADD COLUMN y2 double precision;--计算起始点坐标UPDATE gyroad SET x1 =ST_x(ST_PointN(geom, 1));UPDATE gyroad SET y1 =ST_y(ST_PointN(geom, 1));UPDATE gyroad SET x2 =ST_x(ST_PointN(geom, ST_NumPoints(geom)));UPDATE gyroad SET y2 =ST_y(ST_PointN(geom, ST_NumPoints(geom)));SELECT seq, id1 AS node, id2 AS edge, cost FROM pgr_astar('SELECT gid AS id,source::integer,target::integer,length::double precision AS cost,x1, y1, x2, y2 FROM gyroad',30, 60, false,false);--A*算法路径查询SELECT seq, id1 AS source, id2 AS target,cost FROM pgr_kdijkstraCost('SELECT gid AS id,source::integer,target::integer,length::double precision AS cost FROM gyroad',30,array[60,70,100], false, false);--查询从出发点到⽬的地的消耗SELECT seq, id1 AS path, id2 AS edge, cost FROM pgr_kdijkstraPath('SELECT gid AS id,source::integer,target::integer,length::double precision AS costFROM gyroad',30, array[60,100], false, false);--pgr_kdijkstraPath函数路径分析-------------------------------------------DROP FUNCTION pgr_fromAtoB(varchar, double precision, double precision,-- double precision, double precision);--基于任意两点之间的最短路径分析CREATE OR REPLACE FUNCTION pgr_fromAtoB(IN tbl varchar,--数据库表名IN x1 double precision,--起点x坐标IN y1 double precision,--起点y坐标IN x2 double precision,--终点x坐标IN y2 double precision,--终点y坐标OUT seq integer,--道路序号OUT gid integer,OUT name text,--道路名OUT heading double precision,OUT cost double precision,--消耗OUT geom geometry--道路⼏何集合)RETURNS SETOF record AS$BODY$DECLAREsql text;rec record;source integer;target integer;point integer;BEGIN-- 查询距离出发点最近的道路节点EXECUTE'SELECT id::integer FROM '|| quote_ident(tbl) ||'_vertices_pgrORDER BY the_geom <-> ST_GeometryFromText(''POINT('|| x1 ||''|| y1 ||')'',4326) LIMIT 1'INTO rec;source := rec.id;-- 查询距离⽬的地最近的道路节点EXECUTE'SELECT id::integer FROM '|| quote_ident(tbl) ||'_vertices_pgrORDER BY the_geom <-> ST_GeometryFromText(''POINT('|| x2 ||''|| y2 ||')'',4326) LIMIT 1'INTO rec;target := rec.id;-- 最短路径查询seq :=0;sql :='SELECT gid, geom, name, cost, source, target,ST_Reverse(geom) AS flip_geom FROM '||'pgr_bdAstar(''SELECT gid as id, source::int, target::int, '||'length::float AS cost,x1,y1,x2,y2 FROM '|| quote_ident(tbl) ||''', '|| source ||', '|| target||' ,false, false), '|| quote_ident(tbl) ||' WHERE id2 = gid ORDER BY seq';-- Remember start pointpoint := source;FOR rec IN EXECUTE sqlLOOP-- Flip geometry (if required)IF ( point != rec.source ) THENrec.geom := rec.flip_geom;point := rec.source;ELSEpoint := rec.target;END IF;-- Calculate heading (simplified)EXECUTE'SELECT degrees( ST_Azimuth(ST_StartPoint('''|| rec.geom::text||'''),ST_EndPoint('''|| rec.geom::text||''') ) )'INTO heading;-- Return recordseq := seq +1;gid := rec.gid;name := ;cost := rec.cost;geom := rec.geom;RETURN NEXT;END LOOP;RETURN;END;$BODY$LANGUAGE 'plpgsql' VOLATILE STRICT;-------------------------------------------测试SELECT st_astext(ST_MakeLine(route.geom)) FROM (SELECT seq,gid,name,heading,cost,geom FROM pgr_fromAtoB('gyroad', 106.535, 26.905, 106.955, 27.040)ORDER BY seq) AS route--Openlayers测试--http://localhost:6060/geoserver/PostGIS/wms?service=WMS&version=1.1.0&request=GetMap&layers=PostGIS:shortgyroad&styles=&bbox=104,24,108,28&width=330&height=768&srs=EPSG:4326&format=applicat。

pgstattuple插件逻辑

pgstattuple插件逻辑pgstattuple插件是一个用于统计和展示表中元组（行）信息的扩展插件。

它提供了一种快速查询和了解表中元组的方式，可以帮助开发人员优化数据库性能、调整表结构以及监控数据库的使用情况。

下面将详细介绍pgstattuple插件的使用逻辑。

1.安装和加载插件首先，需要将pgstattuple插件安装到PostgreSQL数据库中。

可以通过以下方法进行安装：（1）使用包管理工具安装：如果使用的是Linux系统，可以使用包管理工具（如yum或apt）进行安装。

例如，在Ubuntu系统上，可以运行以下命令：sudo apt-get install postgresql-<version>-pgstattuple（2）使用源码编译安装：可以从PostgreSQL官方网站下载pgstattuple的源码，然后按照官方文档中的说明进行编译和安装。

安装完成后，需要在数据库中加载pgstattuple插件。

可以使用以下命令加载插件：CREATE EXTENSION pgstattuple;2.查询元组统计信息加载插件后，可以使用pgstattuple函数来查询表的元组统计信息。

pgstattuple函数的使用方式如下：SELECT *FROM pgstattuple('tablename');其中，'tablename'是要查询的表的名称。

pgstattuple函数返回一个包含了表的元组统计信息的记录集。

这些统计信息包括：- live_tuples：表中存储的活动元组（未被删除的元组）的数量。

- dead_tuples：表中存储的被删除元组的数量。

- free_space：表中未使用的空间的大小（以字节为单位）。

- null_frac：表中包含NULL值的比例。

- avg_width：表中每个元组的平均宽度（以字节为单位）。

- n_distinct：表中每个列的不同值的数量。

navicat pg 数据传输配置函数-概述说明以及解释

navicat pg 数据传输配置函数-概述说明以及解释1.引言1.1 概述概述部分Navicat是一款功能强大的数据库管理工具，广泛应用于各种数据库的开发和管理中。

在Navicat中，可以使用其提供的数据传输功能来实现不同数据库之间的数据迁移和同步。

本文主要讨论Navicat中与PG（PostgreSQL）数据库的数据传输配置函数相关的内容。

PG是一种流行的开源关系型数据库，具有良好的可扩展性和稳定性，被广泛应用于各种规模的项目中。

在Navicat中，PG数据传输配置函数提供了一种方便快捷的方式来实现不同数据库之间的数据迁移和同步。

通过配置函数，可以灵活地设置源数据库和目标数据库，选择需要传输的表格和字段，以及定义数据传输的方式和规则。

本文将从Navicat简介开始介绍Navicat的基本功能和特点，然后重点关注PG数据传输配置函数的使用方法和注意事项。

我们将详细讨论如何配置函数来实现数据传输和同步，并介绍一些常见问题和解决方案。

最后，我们将总结本文的主要内容，并展望未来可能的发展方向。

通过阅读本文，读者将了解Navicat的基本概念和功能，掌握PG数据传输配置函数的使用方法，能够灵活地在不同数据库之间进行数据迁移和同步。

同时，读者还将深入理解数据传输和同步过程中需要注意的问题和解决方案，为实际项目中的数据库管理工作提供参考和指导。

接下来，我们将开始介绍Navicat的基本概述和文章结构，为读者提供一个清晰的阅读导向。

1.2文章结构文章结构是指文章的组织和安排方式，它决定了文章的逻辑顺序和内容的呈现方式。

在本文中，文章的结构分为引言、正文和结论三个部分。

引言部分主要介绍文章的背景和目的。

首先，在引言的概述部分，可以简要介绍Navicat PG数据传输配置函数的重要性和应用场景。

然后，在文章结构的描述中，可以概括性地介绍本文的章节组成和各个章节的内容安排，给读者一个整体的了解。

最后，在目的的阐述中，可以明确说明本文的目的是为了介绍Navicat PG数据传输配置函数的使用方法和注意事项，以及提供一些相关的实例和技巧。

postgresql+postgis+pgrouting实现最短路径查询（1）－－－线数据。。。

postgresql+postgis+pgrouting实现最短路径查询（1）－－－线数据。

1、ALTER TABLE beijing_line ADD COLUMN source integer;ALTER TABLE beijing_line ADD COLUMN target integer;ALTER TABLE beijing_line ADD COLUMN length double precision;UPDATE beijing_line SET length = ST_Length(the_geom);ps：执⾏createTopology这个函数之前⼀定得对数据库执⾏以下三句sql查询：CREATE EXTENSION postgis;CREATE EXTENSION postgis_topology;CREATE EXTENSION fuzzystrmatch;2、select pgr_createTopology('beijing_line',0.001,source:='source',id:='gid',target:='target',the_geom:='the_geom');select pgr_createTopology('beijing_line',0.1,source:='source',id:='gid',target:='target',the_geom:='the_geom’);把容差值设置的⼤⼀点，可能结果会好点3、 SELECT * FROM pgr_dijkstra('SELECT gid as id,source::integer,target::integer,length::double precision as costFROM beijing_line',30, 60, false, false);⽆查询结果就执⾏下⾯这⼏个试⼀试，也可能是两点之间就没有路径select source from beijing_line;select target from beijing_line;select length from beijing_line;4、查询所经过的所有点：SELECT st_astext(the_geom) FROM pgr_dijkstra('SELECT gid AS id,source::integer,target::integer,length::double precision AS costFROM beijing_line',30, 60, false, false) as dijoin beijing_line pton di.id2 = pt.gid;5、将路径写⼊⼀个⼏何⽂件内：SELECT seq, id1 AS node, id2 AS edge, cost,the_geom into dijkstra_res FROM pgr_dijkstra('SELECT gid AS id,source::integer,target::integer,length::double precision AS costFROM beijing_line',30, 60, false, false) as dijoin beijing_line pton di.id2 = pt.gid;经历过以上的步骤，如果⼀切顺利，应该能看到结果，这⾥不再截图。

基于PgRouting的GIS网络分析--数据准备（转载）

基于PgRouting的GIS⽹络分析--数据准备（转载）⼀前⾔PgRouting是基于开源空间数据库PostGIS⽤于⽹络分析的扩展模块，最初它被称作pgDijkstra，因为它只是利⽤Dijkstra算法实现最短路径搜索，之后慢慢添加了其他的路径分析算法，如A算法，双向A算法，Dijkstra算法，双向Dijkstra算法，tsp货郎担算法等，然后被更名为pgRouting[1]。

该扩展库依托PostGIS⾃⾝的gist索引，丰富的坐标系与图形类型，强⼤的⼏何处理能⼒，如空间查询，空间处理，线性参考等优势，能保障在较⼤数据级别下的⽹络分析效果更快更好。

PostGIS早已奠定了最优秀的开源空间数据库地位，在新时代GIS中的应⽤将会越来越普遍。

其实，⽹络分析算法很多服务端语⾔如java，C#等虽能实现，但基于真实城市道路数据量较⼤且查询分析操作步骤复杂与数据库交互频繁，以这类服务端频繁访问数据库导致数据库开销压⼒较⼤，分析较慢，故选择PgRouting在数据库内部实现算法，提升分析效率。

最后，路径分析不仅仅是最短路径，在实际应⽤中还有最短耗时，最近距离，道路对车辆类型限制，道路对速度限制等因素，交通事故、市政事故导致的交通障碍点等问题，所有的问题本质其实是对路径分析权重（Weight）的设置问题。

⼆ PgRounting安装windows安装过程⽐较简单，安装PostgreSQL，PostGIS⼀直Next即可，安装完⾃带PgRouting扩展，这⾥主要以Centos7介绍安装过程：1. 安装PostgreSQL，参考；2. 安装PostGIS，PgRouting，具体安装步骤参考；三搭建⽹络分析库3.1 创建测试数据库[root@localhost opt]# su - postgres[postgres@localhost ~]$ psqlpsql (9.6.1)Type "help" for help.postgres=# create database network;CREATE DATABASEpostgres=# \c networkYou are now connected to database "network" as user "postgres".network=# create extension postgis;CREATE EXTENSIONnetwork=# create extension pgrouting;CREATE EXTENSION3.2 导⼊测试路⽹数据PgRouting需要使⽤道路线型数据，建⽴道路连通性topo关系。

PostgreSQL基础教程说明书

About the T utorialPostgreSQL is a powerful, open source object-relational database system. It has more than 15 years of active development and a proven architecture that has earned it a strong reputation for reliability, data integrity, and correctness.PostgreSQL runs on all major operating systems, including Linux, UNIX (AIX, BSD, HP-UX, SGI IRIX, Mac OS X, Solaris, Tru64), and Windows.This tutorial will give you quick start with PostgreSQL and make you comfortable with PostgreSQL programming.AudienceThis tutorial has been prepared for the beginners to help them understand the basic to advanced concepts related to PostgreSQL Database.PrerequisitesBefore you start practicing with various types of examples given in this reference, I'm making an assumption that you are already aware about what is database, especially RDBMS and what is a computer programming language.Copyright & DisclaimerCopyright 2017 by Tutorials Point (I) Pvt. Ltd.All the content and graphics published in this e-book are the property of Tutorials Point (I) Pvt. Ltd. The user of this e-book is prohibited to reuse, retain, copy, distribute or republish any contents or a part of contents of this e-book in any manner without written consent of the publisher.We strive to update the contents of our website and tutorials as timely and as precisely as possible, however, the contents may contain inaccuracies or errors. Tutorials Point (I) Pvt. Ltd. provides no guarantee regarding the accuracy, timeliness or completeness of our website or its contents including this tutorial. If you discover any errors on our website or inthistutorial,******************************************T able of ContentsAbout the Tutorial (i)Audience (i)Prerequisites (i)Copyright & Disclaimer (i)Table of Contents (ii)1.PostgreSQL – Overview (1)Brief History (1)Key Features of PostgreSQL (2)Procedural Languages Support (2)2.PostgreSQL – Environment Setup (3)Installing PostgreSQL on Linux/Unix (3)Installing PostgreSQL on Windows (4)Installing PostgreSQL on Mac (7)3.PostgreSQL – Syntax (11)The SQL Statement (11)PostgreSQL SQL commands (11)4.PostgreSQL – Data Type (35)Numeric Types (35)Monetary Types (36)Character Types (36)Binary Data Types (37)Date/Time Types (37)Boolean Type (37)Enumerated Type (38)Geometric Type (38)Network Address Type (38)Bit String Type (39)Text Search Type (39)UUID Type (39)XML Type (39)JSON Type (40)Array Type (40)Composite Types (41)Range Types (42)Object Identifier Types (43)Pseudo Types (43)5.PostgreSQL – CREATE Database (45)Using createdb Command (45)6.PostgreSQL – SELECT Database (48)Database SQL Prompt (48)OS Command Prompt (49)7.PostgreSQL – DROP Database (50)Using dropdb Command (51)8.PostgreSQL – CREATE Table (53)9.PostgreSQL – DROP Table (55)10.PostgreSQL – Schema (56)Syntax to Create Table in Schema (56)Syntax to Drop Schema (57)11.PostgreSQL – INSERT Query (58)12.PostgreSQL – SELECT Query (60)13.PostgreSQL – Operators (62)PostgreSQL Arithmetic Operators (62)PostgreSQL Comparison Operators (64)PostgreSQL Logical Operators (66)PostgreSQL Bit String Operators (69)14.PostgreSQL – Expressions (71)PostgreSQL – Boolean Expressions (71)PostgreSQL – Numeric Expression (72)PostgreSQL – Date Expressions (73)15.PostgreSQL – WHERE Clause (74)16.PostgreSQL – AND & OR Conjunctive Operators (79)The AND Operator (79)The OR Operator (80)17.PostgreSQL – UPDATE Query (82)18.PostgreSQL – DELETE Query (84)19.PostgreSQL – LIKE Clause (86)20.PostgreSQL – LIMIT Clause (89)21.PostgreSQL – ORDER BY Clause (91)22.PostgreSQL – GROUP BY (94)23.PostgreSQL – WITH Clause (97)Recursive WITH (97)24.PostgreSQL – HAVING Clause (101)25.PostgreSQL – DISTINCT Keyword (104)ADVANCED POSTGRESQL (107)26.PostgreSQL – CONSTRAINTS (108)NOT NULL Constraint (108)UNIQUE Constraint (109)PRIMARY KEY Constraint (109)FOREIGN KEY Constraint (110)CHECK Constraint (111)EXCLUSION Constraint (111)Dropping Constraints (112)27.PostgreSQL – JOINS (113)The CROSS JOIN (114)The INNER JOIN (115)The LEFT OUTER JOIN (116)The RIGHT OUTER JOIN (117)The FULL OUTER JOIN (117)28.PostgreSQL – UNIONS Clause (119)The UNION ALL Clause (121)29.PostgreSQL – NULL Values (123)30.PostgreSQL – ALIAS Syntax (126)31.PostgreSQL – TRIGGERS (129)Listing TRIGGERS (132)Dropping TRIGGERS (132)32.PostgreSQL – INDEXES (133)Index Types (133)The DROP INDEX Command (135)When Should Indexes be Avoided? (135)33.PostgreSQL – ALTER TABLE Command (136)34.PostgreSQL – TRUNCATE TABLE Command (139)35.PostgreSQL – VIEWS (140)Creating Views (140)Dropping Views (142)36.PostgreSQL – TRANSACTIONS (143)Transaction Control (143)The COMMIT Command (144)The ROLLBACK Command (144)37.PostgreSQL – LOCKS (146)DeadLocks (146)Advisory Locks (147)38.PostgreSQL – Sub Queries (148)Subqueries with the SELECT Statement (148)Subqueries with the INSERT Statement (149)Subqueries with the UPDATE Statement (150)Subqueries with the DELETE Statement (151)39.PostgreSQL – AUTO INCREMENT (153)40.PostgreSQL – PRIVILEGES (155)41.PostgreSQL – DATE/TIME Functions and Operators (158)42.PostgreSQL – Functions (166)43.PostgreSQL – Useful Functions (168)PostgreSQL – COUNT Function (168)PostgreSQL – MAX Function (169)PostgreSQL – MIN Function (171)PostgreSQL – AVG Function (172)PostgreSQL – SUM Function (173)PostgreSQL – Array Function (174)PostgreSQL – Numeric Function (175)PostgreSQL – STRING Function (185)POSTGRESQL INTERFACES (197)44.PostgreSQL – C/C++ Interface (198)Installation (198)C/C++ Interface APIs (199)Connecting To Database (200)Create a Table (201)INSERT Operation (202)SELECT Operation (204)UPDATE Operation (206)DELETE Operation (208)45.PostgreSQL – JAVA Interface (211)Installation (211)Connecting To Database (211)Create a Table (212)INSERT Operation (213)SELECT Operation (215)UPDATE Operation (217)DELETE Operation (219)46.PostgreSQL – PHP Interface (222)Installation (222)PHP Interface APIs (222)Connecting to Database (224)Create a Table (225)INSERT Operation (226)SELECT Operation (227)UPDATE Operation (228)DELETE Operation (230)47.PostgreSQL – Perl Interface (233)Installation (233)DBI Interface APIs (234)Connecting to Database (235)Create a Table (235)INSERT Operation (236)SELECT Operation (237)UPDATE Operation (239)DELETE Operation (240)48.PostgreSQL – Python Interface (243)Installation (243)Python psycopg2 module APIs (243)Connecting to Database (245)Create a Table (245)INSERT Operation (246)SELECT Operation (247)UPDATE Operation (248)DELETE Operation (249)PostgreSQL 7PostgreSQL is a powerful, open source object-relational database system. It has more than 15 years of active development phase and a proven architecture that has earned it a strong reputation for reliability, data integrity, and correctness.This tutorial will give you a quick start with PostgreSQL and make you comfortable with PostgreSQL programming.What is PostgreSQL?PostgreSQL (pronounced as post-gress-Q-L ) is an open source relational database management system (DBMS) developed by a worldwide team of volunteers. PostgreSQL is not controlled by any corporation or other private entity and the source code is available free of charge.A Brief History of PostgreSQLPostgreSQL, originally called Postgres, was created at UCB by a computer science professor named Michael Stonebraker. Stonebraker started Postgres in 1986 as a follow-up project to its predecessor, Ingres, now owned by Computer Associates.1. 1977-1985: A project called INGRES was developed.∙Proof-of-concept for relational databases ∙Established the company Ingres in 1980 ∙ Bought by Computer Associates in 19942. 1986-1994: POSTGRES∙ Development of the concepts in INGRES with a focus on object orientation and the query language - Quel∙The code base of INGRES was not used as a basis for POSTGRES ∙ Commercialized as Illustra (bought by Informix, bought by IBM)3. 1994-1995: Postgres95∙Support for SQL was added in 1994 ∙Released as Postgres95 in 1995 ∙Re-released as PostgreSQL 6.0 in 1996 ∙ Establishment of the PostgreSQL Global Development Team1.PostgreSQLKey Features of PostgreSQLPostgreSQL runs on all major operating systems, including Linux, UNIX (AIX, BSD, HP-UX, SGI IRIX, Mac OS X, Solaris, Tru64), and Windows. It supports text, images, sounds, and video, and includes programming interfaces for C / C++, Java, Perl, Python, Ruby, Tcl and Open Database Connectivity (ODBC).PostgreSQL supports a large part of the SQL standard and offers many modern features including the following:∙Complex SQL queries∙SQL Sub-selects∙Foreign keys∙Trigger∙Views∙Transactions∙Multiversion concurrency control (MVCC)∙Streaming Replication (as of 9.0)∙Hot Standby (as of 9.0)You can check official documentation of PostgreSQL to understand the above-mentioned features. PostgreSQL can be extended by the user in many ways. For example by adding new: ∙Data types∙Functions∙Operators∙Aggregate functions∙Index methodsProcedural Languages SupportPostgreSQL supports four standard procedural languages, which allows the users to write their own code in any of the languages and it can be executed by PostgreSQL database server. These procedural languages are - PL/pgSQL, PL/Tcl, PL/Perl and PL/Python. Besides, other non-standard procedural languages like PL/PHP, PL/V8, PL/Ruby, PL/Java, etc., are also supported.8PostgreSQL 9 To start understanding the PostgreSQL basics, first let us install the PostgreSQL. This chapter explains about installing the PostgreSQL on Linux, Windows and Mac OS platforms. Installing PostgreSQL on Linux/UnixFollow the given steps to install PostgreSQL on your Linux machine. Make sure you are logged in as root before you proceed for the installation.∙ Pick the version number of PostgreSQL you want and, as exactly as possible, the platform you want from EnterpriseDB∙I downloaded postgresql-9.2.4-1-linux-x64.run for my 64-bit CentOS-6 machine. Now, let us execute it as follows:∙ Once you launch the installer, it asks you a few basic questions like location of the installation, password of the user who will use database, port number, etc. So keep all of them at their default values except password, which you can provide password as per your choice. It will install PostgreSQL at your Linux machine and will display the following message:∙ Follow the following post-installation steps to create your database:2.10∙You can start/restart postgres server in case it is not running, using thefollowing command:∙If your installation was correct, you will have PotsgreSQL prompt test=# as shown above.Installing PostgreSQL on WindowsFollow the given steps to install PostgreSQL on your Windows machine. Make sure you have turned Third Party Antivirus off while installing.∙Pick the version number of PostgreSQL you want and, as exactly as possible, the platform you want from EnterpriseDB∙I downloaded postgresql-9.2.4-1-windows.exe for my Windows PC running in 32-bit mode, so let us run postgresql-9.2.4-1-windows.exe as administrator to install PostgreSQL. Select the location where you want to install it. By default, it is installed within Program Files folder.11The next step of the installation process would be to select the directory where your data would be stored. By default, it is stored under the "data" directory.12Next, the setup asks for password, so you can use your favorite password.13The next step; keep the port as default.14∙ In the next step, when asked for "Locale", I selected "English, United States".∙It takes a while to install PostgreSQL on your system. On completion of the installation process, you will get the following screen. Uncheck the checkbox and click the Finish button.After the installation process is completed, you can access pgAdmin III, StackBuilder and PostgreSQL shell from your Program Menu under PostgreSQL 9.2.Installing PostgreSQL on MacFollow the given steps to install PostgreSQL on your Mac machine. Make sure you are logged in as administrator before you proceed for the installation.∙∙I downloaded postgresql-9.2.4-1-osx.dmg for my Mac OS running with OS X version 10.8.3. Now, let us open the dmg image in finder and just double click it, which will give you PostgreSQL installer in the following window:15∙Next, click the postgres-9.2.4-1-osx icon, which will give a warning message. Accept the warning and proceed for further installation. It will ask for the administrator password as seen in the following window:∙Enter the password, proceed for the installation, and after this step, restart your Mac machine. If you do not see the following window, start your installation once again.16Once you launch the installer, it asks you a few basic questions like location of the installation, password of the user who will use database, port number etc. Therefore, keep all of them at their default values except the password, which you can provide as per your choice. It will install PostgreSQL in your Mac machine in the Application folder which you can check:17Now, you can launch any of the program to start with. Let us start with SQL Shell.When you launch SQL Shell, just use all the default values it displays except, enter your password, which you had selected at the time of installation. If everything goes fine, then you will be inside postgres database and a postgress#prompt will be displayed as shown below:18Congratulations Now you have your environment ready to start with PostgreSQL database programming.19PostgreSQL20This chapter provides a list of the PostgreSQL SQL commands, followed by the precise syntax rules for each of these commands. This set of commands is taken from the psql command-line tool. Now that you have Postgres installed, open the psql as: Program Files > PostgreSQL 9.2 > SQL Shell(psql).Using psql, you can generate a complete list of commands by using the \help command. For the syntax of a specific command, use the following command: The SQL StatementAn SQL statement is comprised of tokens where each token can represent either a keyword, identifier, quoted identifier, constant, or special character symbol. The table given below uses a simple SELECT statement to illustrate a basic, but complete, SQL statement and its components.PostgreSQL SQL commandsABORTAbort the current transaction. ALTER AGGREGATEChange the definition of an aggregate function. 3.ALTER CONVERSIONChange the definition of a conversion.ALTER DATABASEChange a database specific parameter.ALTER DOMAINChange the definition of a domain specific parameter.ALTER FUNCTIONChange the definition of a function.ALTER GROUPChange a user group.21ALTER INDEXChange the definition of an index.ALTER LANGUAGEChange the definition of a procedural language.ALTER OPERATORChange the definition of an operator.ALTER OPERATOR CLASSChange the definition of an operator class.ALTER SCHEMAChange the definition of a schema.ALTER SEQUENCEChange the definition of a sequence generator.ALTER TABLEChange the definition of a table.Where action is one of the following lines:ALTER TABLESPACE23Change the definition of a tablespace.ALTER TRIGGERChange the definition of a trigger.ALTER TYPEChange the definition of a type.ALTER USERChange a database user account.Where option can be:ANALYZECollect statistics about a database.BEGINStart a transaction block.24Where transaction_mode is one of:CHECKPOINTForce a transaction log checkpoint.CLOSEClose a cursor.CLUSTERCluster a table according to an index.COMMENTDefine or change the comment of an object.25COMMITCommit the current transaction.COPYCopy data between a file and a table.CREATE AGGREGATEDefine a new aggregate function.CREATE CASTDefine a new cast.27CREATE CONSTRAINT TRIGGERDefine a new constraint trigger.CREATE CONVERSIONDefine a new conversion.CREATE DATABASECreate a new database.CREATE DOMAINDefine a new domain.28Where constraint is:CREATE FUNCTIONDefine a new function.CREATE GROUPDefine a new user group.CREATE INDEXDefine a new index.29CREATE LANGUAGEDefine a new procedural language.CREATE OPERATORDefine a new operator.CREATE OPERATOR CLASSDefine a new operator class.30CREATE RULEDefine a new rewrite rule.CREATE SCHEMADefine a new schema.CREATE SEQUENCEDefine a new sequence generator.Define a new table.31Where column_constraint is:And table_constraint is:32End of ebook previewIf you liked what you saw…Buy it from our store @ https://33。

gurobi多目标优化案例

gurobi多目标优化案例
1. 生产调度问题：某工厂生产多种产品，每种产品需要不同的设备和工艺流程。

目标是最大化产量和最小化生产时间。

2. 路径规划问题：在一个城市中，有多个起点和终点，需要找到一条路径，使得总行驶距离最短、总耗时最短。

3. 设备布局问题：在一个工厂中，需要将多个设备布置在不同的位置，以最小化设备之间的距离和最大化设备的利用率。

4. 资源分配问题：某公司有多个项目需要分配资源，包括人力和设备，需要找到最佳的资源分配方案，以最大化总利润和最小化总成本。

5. 物流网络设计问题：某物流公司需要设计一个物流网络，包括仓库和运输路线，以最小化总运输成本和最大化客户满意度。

6. 供应链优化问题：某公司的供应链包括多个环节，包括采购、生产和物流，需要找到最佳的供应链优化方案，以最大化整体效益。

7. 机器学习模型选择问题：在机器学习中，有多个模型可以选择，需要找到最佳的模型组合，以最小化预测误差和最大化模型性能。

8. 资产配置问题：某投资公司需要将资金分配到不同的资产类别中，包括股票、债券和房地产，需要找到最佳的资产配置方案，以最大化总回报和最小化风险。

9. 员工排班问题：某公司有多个员工，需要安排他们的工作时间表，以最小化总工时和最大化员工满意度。

10. 项目调度问题：某项目有多个任务需要完成，每个任务有不同
的时限和资源需求，需要找到最佳的任务调度方案，以最小化总延迟和最大化项目效率。

基于PgRouting图计算的人员精确定位轨迹还原技术

1922021年第4期基于PgRouting 图计算的人员精确定位轨迹还原技术闫启宏李健杜朋浩（贵州黔西能源开发有限公司，贵州黔西 551500）摘要为实现人员精确定位轨迹还原，利用PgRouting 图计算技术，在三维GIS 上实现人员实时轨迹的精确展示。

该方法对局部巷道复杂拓扑结构、定位分站设备缺失、人员轨迹数据缺失等具有极强的鲁棒性。

关键词矿井；人员轨迹；人员精确定位；轨迹还原中图分类号 TD76 文献标识码 A doi:10.3969/j.issn.1005-2801.2021.04.069Restoration Technology of Personnel Precise Positioning Trajectory based on Pgrouting GraphCalculationYan Qihong Li Jian Du Penghao(Guizhou Qianxi Energy Development Co., Ltd., Guizhou Qianxi 551500)Abstract : In order to restore the track of personnel accurate positioning, the PgRouting graph computing technology is used to realize the accurate display of personnel real-time track on 3D GIS. This method has strong robustness to the complex topology of local roadway, the lack of positioning substation equipment and the lack of personnel trajectory data.Key words : mine; personnel trajectory; accurate positioning of personnel; trajectory reduction收稿日期2020-11-28作者简介闫启宏（1967—），男，1990年7月毕业于山东矿业学院电气自动化专业，本科/学士，高级工程师，现任贵州黔西能源开发有限公司副总经理。

postgresql explain plan 解读

postgresql explain plan 解读全文共四篇示例，供读者参考第一篇示例：执行以上语句后，PostgreSQL会返回一份详细的执行计划信息，我们可以从中了解查询是如何执行的，哪些索引被使用了，以及查询的执行成本等等。

通过分析这些信息，我们可以找出查询的瓶颈所在，并采取相应的措施进行优化。

1. Seq Scan（顺序扫描）：表示数据库系统对表进行全表扫描，这通常会导致查询性能较慢。

2. Index Scan（索引扫描）：表示数据库系统使用了索引进行查询，这通常会提高查询性能。

3. Hash Join（哈希连接）：表示数据库系统使用了哈希连接算法对两张表进行连接，这通常会比嵌套循环连接更高效。

4. Sort（排序）：表示数据库系统对查询结果进行排序操作，这通常会增加查询的执行时间。

5. Nested Loop（嵌套循环）：表示数据库系统使用了嵌套循环连接算法对两张表进行连接，这通常会导致性能较差。

第二篇示例：PostgreSQL 是一个强大的开源关系型数据库管理系统，其性能优秀而且功能强大。

在PostgreSQL 中，优化查询语句的性能是非常重要的，而EXPLAIN PLAN 是一个非常有用的工具，可以帮助我们理解查询语句的执行计划，并从中找到优化的方向。

在本文中，我们将深入探讨PostgreSQL 中的EXPLAIN PLAN，帮助读者更好地理解和利用这一工具。

首先，让我们简单介绍一下EXPLAIN PLAN 的作用。

在PostgreSQL 中，EXPLAIN PLAN 是一个指令，用来分析查询语句的执行计划。

通过执行EXPLAIN PLAN 指令，我们可以获得查询语句在数据库引擎中执行的详细信息，包括具体的执行顺序、执行计划、索引使用情况等等。

这些信息可以帮助我们评估查询语句的性能，并找到优化方向。

在PostgreSQL 中，执行EXPLAIN PLAN 的指令非常简单，只需要在查询语句前添加关键字EXPLAIN 即可。

pgRoutingDocumentation

pgRouting Manual Release2.0.0(d4d49b7master)pgRouting ContributorsSeptember20,2013ContentspgRouting Manual,Release2.0.0(d4d49b7master) pgRouting extends the PostGIS1/PostgreSQL2geospatial database to provide geospatial routing and other networkanalysis functionality.This is the manual for pgRouting2.0.0(d4d49b7master).The pgRouting Manual is licensed under a Creative Commons Attribution-Share Alike3.0License3.Feel free to use this material any way you like,but we ask that you attribute credit to the pgRouting Project and wherever possible,a link back to .For other licenses used in pgRouting see the License page.123/licenses/by-sa/3.0/pgRouting Manual,Release2.0.0(d4d49b7master)CHAPTER1General1.1IntroductionpgRouting is an extension of PostGIS1and PostgreSQL2geospatial database and adds routing and other network analysis functionality.A predecessor of pgRouting–pgDijkstra,written by Sylvain Pasche from Camptocamp3, was later extended by Orkney4and renamed to pgRouting.The project is now supported and maintained by Georepublic5,iMaptools6and a broad user community.pgRouting is an OSGeo Labs7project of the OSGeo Foundation8and included on OSGeo Live9.1.1.1LicenseThe following licenses can be found in pgRouting:LicenseGNU General Public License,version2Most features of pgRouting are available under GNU General Public License,version210.Boost Software License-Version1.0Some Boost extensions are available under Boost Software License-Version 1.011.MIT-X License Some code contributed by is available under MIT-X license.Creative Commons Attribution-Share Alike3.0 License The pgRouting Manual is licensed under a Creative Commons Attribution-Share Alike3.0License12.In general license information should be included in the header of each sourceﬁle.1234http://www.orkney.co.jp56/7/wiki/OSGeo_Labs89/10/licenses/gpl-2.0.html11/LICENSE_1_0.txt12/licenses/by-sa/3.0/pgRouting Manual,Release2.0.0(d4d49b7master)1.1.2ContributorsIndividuals(in alphabetical order)Akio Takubo,Anton Patrushev,Ashraf Hossain,Christian Gonzalez,Daniel Kastl,Dave Potts,DavidTecher,Ema Miyawaki,Florian Thurkow,Frederic Junod,Gerald Fenoy,Jay Mahadeokar,JinfuLeng,Kai Behncke,Kishore Kumar,Ko Nagase,Mario Basa,Martin Wiesenhaan,Razequl Islam,Stephen Woodbridge,Sylvain Housseman,Sylvain Pasche,Virginia VergaraCorporate Sponsors(in alphabetical order)These are corporate entities that have contributed developer time,hosting,or direct monetary funding to the pgRouting project:Camptocamp,CSIS(University of Tokyo),Georepublic,Google Summer of Code,iMaptools,Orkney,Paragon Corporation1.1.3More Information•The latest software,documentation and news items are available at the pgRouting web site .•PostgreSQL database server at the PostgreSQL main site .•PostGIS extension at the PostGIS project web site .•Boost C++source libraries at .•Computational Geometry Algorithms Library(CGAL)at .1.2InstallationBinary packages are provided for the current version on the following platforms:1.2.1WindowsWinnie Bot Experimental Builds:•PostgreSQL9.232-bit,64-bit131.2.2Ubuntu/DebianUbuntu packages are available in Launchpad repositories:•stable https:///~georepublic/+archive/pgrouting•unstable https:///~georepublic/+archive/pgrouting-unstableUse UbuntuGIS-unstable PPA14to install PostGIS2.0.13/download/windows/pg92/buildbot/14https:///ubuntugis/+archive/ubuntugis-unstablepgRouting Manual,Release 2.0.0(d4d49b7master)1.2.3RHEL/CentOS/Fedora•Fedora RPM’s:https:///pkgdb/acls/name/pgRouting1.2.4OS X•Homebrew1.2.5Source Package Git2.0.0-rc1releasev2.0.0-rc1.tar.gz 15v2.0.0-rc1.zip 16Git2.0.0-betareleasev2.0.0-beta.tar.gz 17v2.0.0-beta.zip 18Git2.0.0-alphareleasev2.0.0-alpha.tar.gz 19v2.0.0-alpha.zip 20Git masterbranchmaster.tar.gz 21master.zip 22Git developbranch develop.tar.gz 23develop.zip 241.2.6Using GitGit protocol (read-only):HTTPS protocol (read-only):..code-block::bashgit clone https:///pgRouting/pgrouting.gitSee Build Guide for notes on compiling from source.1.3Build GuideTo be able to compile pgRouting make sure that the following dependencies are met:•C and C++compilers•Postgresql version >=8.4(>=9.1recommended)•PostGIS version >=1.5(>=2.0recommended)15https:///pgRouting/pgrouting/archive/v2.0.0-rc1.tar.gz16https:///pgRouting/pgrouting/archive/v2.0.0-rc1.zip17https:///pgRouting/pgrouting/archive/v2.0.0-beta.tar.gz18https:///pgRouting/pgrouting/archive/v2.0.0-beta.zip19https:///pgRouting/pgrouting/archive/v2.0.0-alpha.tar.gz20https:///pgRouting/pgrouting/archive/v2.0.0-alpha.zip21https:///pgRouting/pgrouting/archive/master.tar.gz22https:///pgRouting/pgrouting/archive/master.zip23https:///pgRouting/pgrouting/archive/develop.tar.gz24https:///pgRouting/pgrouting/archive/develop.zippgRouting Manual,Release2.0.0(d4d49b7master)•The Boost Graph Library(BGL).Version>=[TBD]•CMake>=2.8.8•(optional,for Driving Distance)CGAL>=[TBD]•(optional,for Documentation)Sphinx>=1.1•(optional,for Documentation as PDF)Latex>=[TBD]The cmake system has variables the can be conﬁgured via the command line options by setting them with-D<varable>=<value>.You can get a listing of these via:Currently these are:Boost_DIR:PATH=Boost_DIR-NOTFOUND CMAKE_BUILD_TYPE:STRING=CMAKE_INSTALL_PREFIX:PATH=/usr/local POSTGRESQL_EXECUTABLE:FILEPATH=/usr/lib/postgresql/9.2/bin/post POSTGRESQL_PG_CONFIG:FILEPATH=/usr/bin/pg_conﬁg WITH_DD:BOOL=ONWITH_DOC:BOOL=OFF BUILD_HTML:BOOL=ON BUILD_LATEX:BOOL=OFFBUILD_MAN:BOOL=ONThese also show the current or default values based on our development system.So your values my be different.In general the ones that are of most interest are:WITH_DD:BOOL=ON–Turn on/off building driving distance code.WITH_DOC:BOOL=OFF–Turn on/off building the documentation BUILD_HTML:BOOL=ON–If WITH_DOC=ON,turnon/off building HTML BUILD_LATEX:BOOL=OFF–If WITH_DOC=ON,turn on/off buildingPDF BUILD_MAN:BOOL=ON–If WITH_DOC=ON,turn on/off building MAN pagesTo change any of these add-D<variable>=<value>to the cmake lines below.For example to turn on documentation,your cmake command might look like:If you turn on the documentation,you also need to add the doc target to the make command.1.3.1For MinGW on Windows1.3.2For LinuxpgRouting Manual,Release2.0.0(d4d49b7master) 1.3.3With DocumentationBuild with documentation(requires Sphinx25):Rebuild modiﬁed documentation only:1.4SupportpgRouting community support is available through website26,documentation27,tutorials,mailing lists and others. If you’re looking for commercial support,ﬁnd below a list of companies providing pgRouting development and consulting services.1.4.1Reporting ProblemsBugs are reported and managed in an issue tracker28.Please follow these steps:1.Search the tickets to see if your problem has already been reported.If so,add any extra context you mighthave found,or at least indicate that you too are having the problem.This will help us prioritize common issues.2.If your problem is unreported,create a new issue29for it.3.In your report include explicit instructions to replicate your issue.The best tickets include the exact SQLnecessary to replicate a problem.4.If you can test older versions of PostGIS for your problem,please do.On your ticket,note the earliestversion the problem appears.5.For the versions where you can replicate the problem,note the operating system and version of pgRouting,PostGIS and PostgreSQL.6.It is recommended to use the following wrapper on the problem to pin point the step that is causing theproblem.1.4.2Mailing List and GIS StackExchangeThere are two mailing lists for pgRouting hosted on OSGeo mailing list server:•User mailing list:/mailman/listinfo/pgrouting-users•Developer mailing list:/mailman/listinfo/pgrouting-devFor general questions and topics about how to use pgRouting,please write to the user mailing list.25/262728https:///pgrouting/pgrouting/issues29https:///pgRouting/pgrouting/issues/newpgRouting Manual,Release2.0.0(d4d49b7master)You can also ask at GIS StackExchange30and tag the question with pgrouting.Find all questions tagged with pgrouting under /questions/tagged/pgrouting or subscribe to the pgRouting questions feed31.1.4.3Commercial SupportFor users who require professional support,development and consulting services,consider contacting any of the following organizations,which have signiﬁcantly contributed to the development of pgRouting:Company Ofﬁces in WebsiteGeorepublic Germany,Japan iMaptools United States Orkney Inc.Japan http://www.orkney.co.jpCamptocamp Switzerland,France 30/31/feeds/tag?tagnames=pgrouting&sort=newestCHAPTER2Tutorial2.1Tutorial2.1.1Getting StartedThis is a simple guide to walk you through the steps of getting started with pgRouting.In this guide we will cover:•How to create a database to use for our project•How to load some data•How to build a topology•How to check your graph for errors•How to compute a route•How to use other tools to view your graph and route•How to create a web appHow to create a database to use for our projectTheﬁrst thing we need to do is create a database and load pgrouting in the database.Typically you will create a database for each project.Once you have a database to work in,your can load your data and build your application in that database.This makes it easy to move your project later if you want to to say a production server.For Postgresql9.1and later versionsFor older versions of postgresqlpgRouting Manual,Release2.0.0(d4d49b7master)How to load some dataHow you load your data will depend in what form it comes it.There are various OpenSource tools that can help you,like:shp2pgsql•this is the postgresql shapeﬁle loaderogr2ogr•this is a vector data conversion utilityosm2pgsql•this is a tool for loading OSM data into postgresqlSo these tools and probably others will allow you to read vector data and and can load that data into your database as a table of some kind.At this point you need to know a little about your data structure and content.One easy way to browse you data table is with pgAdmin3or phpPgAdmin.How to build a topologyNext we need to build a topology for our street data.What this means is that for any given edge in your street data the ends of that edge will be connected to a unique node and to other edges that are also connected to that same unique node.Once all the edges are connected to nodes we have a graph that can be used for routing with pgrouting.We provide a tools the will help with this:See pgr_createTopology for more information.How to check your graph for errorsThere are lots of possible sources for errors in a graph.The data that you started with may not have been designed with routing in mind.A graph as some very speciﬁc requirments.One it that it is NODED,this means that except for some very speciﬁc use cases,each road segments starts and ends at a node and that in general is does not cross another road segment that it should be connected to.There can be other errors like the direction of a one-way street being entered in the wrong direction.We do not have tools to search for all possible errors but we have some basic tools that might help.See Graph Analytics for more information.If your data needs to be NODED,we have a tool that can help for that also.See pgr_nodeNetwork for more information.How to compute a routeOnce you have all the prep work done above,computing a route is fairly easy.We have a lot of different algorithms but they can work with your prepared road network.The general form of a route query is:As you can see this is fairly straight forward and you can look and the speciﬁc algorithms for the details on how to use them.What you get as a result from these queries will be a set of record of type pgr_costResult[]or pgr_geomResult[].These results have information like edge id and/or the node id along with the cost or geometrypgRouting Manual,Release2.0.0(d4d49b7master) for the step in the path from start to ing the ids you can join these result back to your edge table to getmore information about each step in the path.•See also pgr_costResult[]and pgr_geomResult[].How to use other tools to view your graph and routeTBDHow to create a web appTBD2.1.2Routing TopologyAuthor Stephen Woodbridge<woodbri@1>Copyright Stephen Woodbridge.The source code is released under the MIT-X license.OverviewTypically when GISﬁles are loaded into the data database for use with pgRouting they do not have topology information associated with them.To create a useful topology the data needs to be“noded”.This means that where two or more roads form an intersection there it needs to be a node at the intersection and all the road segments need to be broken at the intersection,assuming that you can navigate from any of these segments to any other segment via that intersection.You can use the graph analysis functions to help you see where you might have topology problems in your data. If you need to node your data,we also have a function pgr_nodeNetwork()that might work for you.This function splits ALL crossing segments and nodes them.There are some cases where this might NOT be the right thing to do.For example,when you have an overpass and underpass intersection,you do not want these noded,but pgr_nodeNetwork does not know that is the case and will node them which is not good because then the router will be able to turn off the overpass onto the underpass like it was aﬂat2D intersection.To deal with this problem some data sets use z-levels at these types of intersections and other data might not node these intersection which would be ok.For those cases where topology needs to be added the following functions may be useful.One way to prep the data for pgRouting is to add the following columns to your table and then populate them as appropriate.This example makes a lot of assumption like that you original data tables already has certain columns in it like one_way,fcc, and possibly others and that they contain speciﬁc data values.This is only to give you an idea of what you can do with your data.1woodbri@pgRouting Manual,Release2.0.0(d4d49b7master)The function pgr_createTopology()will create the vertices_tmp table and populate the source and target columns.The following example populated the remaining columns.In this example,the fcc column contains feature class code and the CASE statements converts it to an average speed.,pgRouting Manual,Release2.0.0(d4d49b7master)Now your database should be ready to use any(most?)of the pgRouting algorithms.See Also•pgr_createTopology•pgr_nodeNetwork•pgr_pointToId2.1.3Graph AnalyticsAuthor Stephen Woodbridge<woodbri@2>Copyright Stephen Woodbridge.The source code is released under the MIT-X license.OverviewIt is common toﬁnd problems with graphs that have not been constructed fully noded or in graphs with z-levels at intersection that have been entered incorrectly.An other problem is one way streets that have been entered in the wrong direction.We can not detect errors with respect to“ground”truth,but we can look for inconsistencies and some anomalies in a graph and report them for additional inspections.We do not current have any visualization tools for these problems,but I have used mapserver to render the graph and highlight potential problem areas.Someone familiar with graphviz might contribute tools for generating images with that.Analyze a GraphWith pgr_analyzeGraph the graph can be checked for errors.For example for table“mytab”that has “mytab_vertices_pgr”as the vertices table:In the vertices table“mytab_vertices_pgr”:•Deadends are indentiﬁed by cnt=1•Potencial gap problems are identiﬁed with chk=1.2woodbri@pgRouting Manual,Release2.0.0(d4d49b7master)For isolated road segments,for example,a segment where both ends are deadends.you canﬁnd these with the following query:If you want to visualize these on a graphic image,then you can use something like mapserver to render the edges and the vertices and style based on cnt or if they are isolated,etc.You can also do this with a tool like graphviz, or geoserver or other similar tools.Analyze One Way Streetspgr_analyzeOneway analyzes one way streets in a graph and identiﬁes anyﬂipped segments.Basically if you count the edges coming into a node and the edges exiting a node the number has to be greater than one.This query will add two columns to the vertices_tmp table ein int and eout int and populate it with the ap-propriate counts.After running this on a graph you can identify nodes with potential problems with the following query.The rules are deﬁned as an array of text strings that if match the col value would be counted as true for the source or target in or out condition.ExampleLets assume we have a table“st”of edges and a column“one_way”that might have values like:•‘FT’-oneway from the source to the target node.•‘TF’-oneway from the target to the source node.•‘B’-two way street.•‘’-emptyﬁeld,assume twoway.•<NULL>-NULLﬁeld,use two_way_if_nullﬂag.Then we could form the following query to analyze the oneway streets for errors.pgRouting Manual,Release2.0.0(d4d49b7master);Typically these problems are generated by a break in the network,the one way direction set wrong,maybe an errorrelated to z-levels or a network that is not properly noded.The above tools do not detect all network issues,but they will identify some common problems.There are otherproblems that are hard to detect because they are more global in nature like multiple disconnected networks.Thinkof an island with a road network that is not connected to the mainland network because the bridge or ferry routesare missing.See Also•pgr_analyzeGraph•pgr_analyzeOneway•pgr_nodeNetwork2.1.4Custom QueryIn general,the routing algorithms need an SQL query that contain one or more of the following required columnswith the preferred type:id int4source int4target int4costﬂoat8reverse_costﬂoat8xﬂoat8yﬂoat8x1ﬂoat8y1ﬂoat8x2ﬂoat8y2ﬂoat8When the edge table has the mentioned columns,the following SQL queries can be used.When the edge table has a different name to represent the required columns:as y2,Rco The topology functions use the same names for id,source and target columns of the edge table,The fowl-lowing parameters have as default value:id int4Default idsource int4Default sourcetarget int4Default targetpgRouting Manual,Release2.0.0(d4d49b7master)the_geom text Default the_geomoneway text Default onewayrows_where text Default true to indicate all rows(this is not a column)The following parameters do not have a default value and when used they have to be inserted in strict order: edge_table texttoleranceﬂoat8s_in_rules text[]s_out_rules text[]t_in_rules text[]t_out_rules text[]When the columns required have the default names this can be used(pgr_func is to represent a topology function)When the columns required do not have the default names its strongly recomended to use the named notation.2.1.5Performance TipsWhen“you know”that you are going to remove a set of edges from the edges table,and without those edges youare going to use a routing function you can do the following:Analize the new topology based on the actual topology:Or create a new topology if the change is permanent:Use an SQL that“removes”the edges in the routing functionWhen“you know”that the route will not go out of a particular area,to speed up the process you can use a more complex SQL query like=5) Note that the same condition id<17is used in all cases.pgRouting Manual,Release2.0.0(d4d49b7master) 2.1.6User’s wrapper contributionsHow to contribute.Use an issue tracker(see Support)with a title containing:Proposing a wrapper:Mywrappername.The body will contain:•author:Required•mail:if you are subscribed to the developers list this is not necessary•date:Date posted•comments and code:using reStructuredText formatAny contact with the author will be done using the developers mailing list.The pgRouting team will evaluate the wrapper and will be included it in this section when approved.No contributions at this time2.1.7Use’s Recipes contributionsHow to contribute.Use an issue tracker(see Support)with a title containing:Proposing a Recipe:Myrecipename.The body will contain:•author:Required•mail:if you are subscribed to the developers list this is not necessary•date:Date posted•comments and code:using reStructuredText formatAny contact with the author will be done using the developers mailing list.The pgRouting team will evaluate the recipe and will be included it in this section when approved.Comparing topology of a unnoded network with a noded networkAuthor pgRouting team.This recipe uses the Sample Data network.No more contributions2.2Sample DataThe documentation provides very simple example queries based on a small sample network.To be able to execute the sample queries,run the following SQL commands to create a table with a small network data set.pgRouting Manual,Release2.0.0(d4d49b7master)Create tableInsert network data,3.4);waysof the Ldirection Before you test a routing function use this query toﬁll the source and target columns.This table is used in some of our examplespgRouting Manual,Release2.0.0(d4d49b7master) The network created in edge_tableFor a more complete introduction how to build a routing application read the pgRouting Workshop3.3pgRouting Manual,Release2.0.0(d4d49b7master)CHAPTER3Data Types3.1pgRouting Data TypesThe following are commonly used data types for some of the pgRouting functions.3.1.1pgr_costResult[]Namepgr_costResult[]—A set of records to describe a path result with cost attribute.Descriptionseq sequential ID indicating the path orderid1generic name,to be speciﬁed by the function,typically the node idid2generic name,to be speciﬁed by the function,typically the edge idcost cost attribute3.1.2pgr_costResult3[]-Multiple Path Results with CostNamepgr_costResult3[]—A set of records to describe a path result with cost attribute.DescriptionpgRouting Manual,Release2.0.0(d4d49b7master)seq sequential ID indicating the path orderid1generic name,to be speciﬁed by the function,typically the path idid2generic name,to be speciﬁed by the function,typically the node idid3generic name,to be speciﬁed by the function,typically the edge idcost cost attributeHistory•New in version2.0.0•Replaces path_resultSee Also•Introduction3.1.3pgr_geomResult[]Namepgr_geomResult[]—A set of records to describe a path result with geometry attribute. Descriptionseq sequential ID indicating the path orderid1generic name,to be speciﬁed by the functionid2generic name,to be speciﬁed by the functiongeom geometry attributeHistory•New in version2.0.0•Replaces geomspgRouting Manual,Release2.0.0(d4d49b7master)See Also•IntroductionpgRouting Manual,Release2.0.0(d4d49b7master)CHAPTER4Functions reference4.1Topology FunctionsThe pgRouting’s topology of a network,represented with an edge table with source and target attributes and a vertices table associated with it.Depending on the algorithm,you can create a topology or just reconstruct the vertices table,You can analyze the topology,We also provide a function to node an unoded network.4.1.1pgr_createTopologyNamepgr_createTopology—Builds a network topology based on the geometry information.SynopsisThe function returns:•OK after the network topology has been built and the vertices table created.•FAIL when the network topology was not built due to an error.) DescriptionParametersThe topology creation function accepts the following parameters:edge_table text Network table name.(may contain the schema name AS well)tolerance float8Snapping tolerance of disconnected edges.(in projection unit)the_geom text Geometry column name of the network table.Default value is the_geom.id text Primary key column name of the network table.Default value is id.source text Source column name of the network table.Default value is source.target text Target column name of the network table.Default value is target.pgRouting Manual,Release2.0.0(d4d49b7master)rows_where text Condition to SELECT a subset or rows.Default value is true to indicate all rows.Warning:The edge_table will be affected•The source column values will change.•The target column values will change.•An index will be created,if it doesn’t exists,to speed up the process to the following columns:–id–the_geom–source–targetThe function returns:•OK after the network topology has been built.–Creates a vertices table:<edge_table>_vertices_pgr.–Fills id and the_geom columns of the vertices table.–Fills the source and target columns of the edge table referencing the id of the vertices table.•FAIL when the network topology was not built due to an error:–A required column of the Network table is not found or is not of the appropriate type.–The condition is not well formed.–The names of source,target or id are the same.–The SRID of the geometry could not be determined.The Vertices TableThe vertices table is a requirment of the pgr_analyzeGraph and the pgr_analyzeOneway functions.The structure of the vertices table is:id bigint Identiﬁer of the vertex.cnt integer Number of vertices in the edge_table that reference this vertex.See pgr_analyzeGraph.chk integer Indicator that the vertex might have a problem.See pgr_analyzeGraph.ein integer Number of vertices in the edge_table that reference this vertex AS incoming.See pgr_analyzeOneway.eout integer Number of vertices in the edge_table that reference this vertex AS outgoing.See pgr_analyzeOneway.the_geom geometry Point geometry of the vertex.History•Renamed in version2.0.0Usage when the edge table’s columns MATCH the default values:The simplest way to use pgr_createtopology is:When the arguments are given in the order described in the parameters:We get the same result AS the simplest way to use the function.Warning:An error would occur when the arguments are not given in the appropriate order:In this example,the columnid of the table ege_table is passed to the function AS the geometry column,and the geometry columnthe_geom is passed to the function AS the id column.SELECTpgr_createTopology(’edge_table’,0.001,’id’,’the_geom’,’source’,’target’);ERROR:Can not determine the srid of the geometry“id”in table public.edge_tableWhen using the named notationThe order of the parameters do not matter:,targe,the_geom: Parameters deﬁned with a default value can be omited,AS long AS the value matches the default:Selecting rows using rows_where parameterSelecting rows based on the id.Selecting the rows where the geometry is near the geometry of row with id=5.Selecting the rows where the geometry is near the geometry of the row with gid=100of the table othertable.Usage when the edge table’s columns DO NOT MATCH the default values:For the following tabletgt FROM ed Using positional notation:The arguments need to be given in the order described in the parameters:。

Routing——管道系统零件设计库的要求

Routing——管道系统零件设计库的要求管路系统零件库的设计要求为了快捷高效地完成管路系统设计任务，根据设计标准的要求建立相关的零件库是最基础，也是最关键的一个步骤。

涉及到SolidWorks软件的内部计算问题和软件不同语言版本的兼容问题，建立管道零件时，在能够使用英语的地方尽量使用英语。

建议读者在SolidWorks 提供的库零件基础上进行改进，这是一个比较简单实用的方法。

管道零件管道零件（pipe）作为管道系统中的主要零件，由于需要与其他附件进行匹配，因此在设计上对特征类型、名称、草图和尺寸有特定的要求。

如图7-11 所示，管道零件的特征和草图具有如下要求：‰ 拉伸特征的名称为“Extrusion”，草图名称为“PipeSketch”。

‰ 拉伸特征的长度尺寸名称为“Length@Extrusion”，草图中包含两个尺寸（外径和内径），其名称分别为“OuterDiameter@PipeSketch ”和“InnerDiameter@PipeSketch”。

‰“FilterSketch ”草图中包含一个尺寸名称位“NominalDiameter ”的圆，是管道名义直径的过滤器草图，用于定义管道的名义直径。

图7-11 管道零件如图7-12 所示，管道零件的设计表参数中，除添加必要的尺寸控制参数外，必须包含如下设计表参数：‰NominalDiameter@FilterSketetch ：用于定义管子的名义直径。

‰$属性@ Pipe Identifier ：管道识别符，用于识别或筛选管道的规格；其中，管道识别符参数用于从管路开始点和管路附件中筛选符合规格的配置，另外，管道识别符还用于管道零件保存时的命名以及在工程图材料明细表中的显示名称。

·268·SolidWorks2007 装配体实例精粹图7-12 管道零件设计表的要求管筒零件由于软管道可以使用样条线或直线完成布局，因此在管筒零件与管道零件不同，其基体特征需要使用扫描特征来完成。

Postgresql的任务计划pgAgent安装与使用

pgAgent安装pgAgent作为postgresql的一个任务调度代理，在postgresql 9.0 以前是附带在pgadmin包下面的，只是默认不安装，9.0之后作为了一个单独是的安装包。

所以要使用pgagent定时任务调度的话还得单独安装。

在安装pgagent之前还需要安装另外的2个依赖包，cmake以及wxGTK，环境CentOS6.2postgresql 9.5.6pgagent-3.4.0 下载地址：https:///download/pgagent.PHPcmake-3.8.1 下载地址：/download/wxGTK-3.1.0 下载地址：/downloads/二、cmake的安装将安装包上传至服务器并解压，解压后进入解压后生成的cmake-3.8.1目录，执行以下命令。

[root@localhostpgAgent]# gunzippgagent-3.4.0.tar.gz[root@localhostpgAgent]# tar-xf pgagent-3.4.0.tar[root@localhostpgAgent]# cd cmake-3.8.1[root@localhost cmake-3.8.1]# ./configure --prefix=/usr/local/cmake3.8.1[root@ localhost cmake-3.8.1]# make[root@ localhost cmake-3.8.1]# make install默认安装在/usr/local/share/cmake-3.8/completions/cmake/usr/local/bin/cmake默认安装不需要在设置环境变量指定目录安装后vi /etc/profileexport PATH=/usr/local/cmake3.8.1/bin:$PATHsource /etc/profile三、wxGTK的安装wxwidgets是一个c++编写的用来提供gui开发的框架。

如何使用PostgreSQL进行中文全文检索

如何使⽤PostgreSQL进⾏中⽂全⽂检索⽬录开始安装插件启动配置Host权限服务器配置分词SCWSzhpaserSQL优化添加⾃定义词典扩展总结开始安装⾸先是安装 PgSQL，这⾥我使⽤的是 PgSQL 9.6，PgSQL 10 也刚发布了，有兴趣的可以尝下鲜。

PgSQL 的安装可以说⾮常复杂了，除了要安装 Server 和 Client 外，还需要安装 devel 包。

为了实现空间索引功能，我们还要安装最重要的 PostGIS 插件，此插件需要很多依赖，⾃⼰⼿动安装⾮常复杂⽽且很可能出错。

推荐⾃动化⽅式安装，Yum ⼀定要配合 epel 这样的 Yum 源，保障能将依赖⼀⽹打尽。

当然最好的还是使⽤ docker 来运⾏，找个镜像就⾏了。

插件由于 PgSQL 的很多功能都由插件实现，所以还要安装⼀些常⽤的插件，如:postgis_topology（管理⾯、边、点等拓扑对象）pgrouting（路径规划）postgis_sfcgal（实现3D相关算法）fuzzystrmatch（字符串相似度计算）address_standardizer/address_standardizer_data_us（地址标准化）pg_trgm（分词索引）这些插件在安装⽬录 /path/extensions 下编译完毕后，在数据库中使⽤前要先使⽤ create extension xxx 启⽤。

启动1.切换到⾮ root ⽤户。

（PgSQL 在安装完毕后会创建⼀个名为 postgres 的超级⽤户，我们可以使⽤这个超级⽤户来操作 PgSQL，后期建议重新创建⼀个普通⽤户⽤来管理数据）；2.切换到 /installPath/bin/ ⽬录下，PgSQL 在此⽬录下提供了很多命令，如 createdb、createuser、dropdb、pg_dump 等；3.使⽤ createdb 命令初始化⼀个⽂件夹 dir_db (此⽬录不能已存在)存放数据库物理数据，使⽤ -E UTF8 参数指定数据库字符集为 utf-8；4.使⽤ pg_ctl -D dir_db 指定数据库启动后台服务；5.使⽤ psql -d db 在命令⾏登陆 PgSQL;配置安装完毕后还要配置⼀些⽐较基本的参数才能正常使⽤。