PG::UndefinedFile: 错误：无法打开扩展控制文件

Question

升级 Postgres 后，当我尝试迁移数据库时出现以下错误。

enable_extension(:postgis)
  SQL (17.2ms)  CREATE EXTENSION IF NOT EXISTS "postgis"
PG::UndefinedFile: ERROR:  could not open extension control file "/usr/local/Cellar/postgresql/9.4.5/share/postgresql/extension/postgis.control": No such file or directory
: CREATE EXTENSION IF NOT EXISTS "postgis"
   (0.3ms)  ROLLBACK
rake aborted!
StandardError: An error has occurred, this and all later migrations canceled:

PG::UndefinedFile: ERROR:  could not open extension control file "/usr/local/Cellar/postgresql/9.4.5/share/postgresql/extension/postgis.control": No such file or directory
: CREATE EXTENSION IF NOT EXISTS "postgis"/Users/harshamv/Sites/clink/db/migrate/20150812164615_enable_postgis.rb:3:in `change'
-e:1:in `<main>'
ActiveRecord::StatementInvalid: PG::UndefinedFile: ERROR:  could not open extension control file "/usr/local/Cellar/postgresql/9.4.5/share/postgresql/extension/postgis.control": No such file or directory
: CREATE EXTENSION IF NOT EXISTS "postgis"
/Users/harshamv/Sites/clink/db/migrate/20150812164615_enable_postgis.rb:3:in `change'
-e:1:in `<main>'
PG::UndefinedFile: ERROR:  could not open extension control file "/usr/local/Cellar/postgresql/9.4.5/share/postgresql/extension/postgis.control": No such file or directory
/Users/harshamv/Sites/clink/db/migrate/20150812164615_enable_postgis.rb:3:in `change'
-e:1:in `<main>'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)

不知道从哪里开始。 大多数其他问题似乎与 Linux 有关，当我尝试创建符号链接时它也不起作用。

Answer 1

你应该安装 postgresql-9.4-postgis-2.1

Answer 2

对于 MacOS，使用以下命令安装 postgis 对我有用：

brew install postgis

对于 Ubuntu，以下命令有效：

sudo apt install postgresql-10-postgis-scripts

Answer 3

检测可用的 postgresql postgis 版本

sudo apt-cache search postgis

安装

sudo apt install postgresql-12-postgis-3-scripts 

切换 postgres 用户

sudo -i -u postgres

创建一个数据库，然后连接它。 在此之后运行 postgis 扩展激活命令

CREATE EXTENSION postgis;

稍后您可以通过以下方式检查并验证它

SELECT PostGIS_version();