Postgres uses dblink

In Oracle, dblink is often used to import some online data to the development database to locate the problem.

Dblink can also be used in PostgreSQL.

The following is an online document:

1. How to Create dblink in PostgreSQL?
2. How do I use dblink after the build is successful?
3. What is the difference between dblink in PostgreSQL and dblink in Oracle?

The solution is as follows:

Question 1:

# Useradd postgre (automatically create a postgre Group)

Decompress the package to/usr/local/src:
# Tar xvfz postgresql-7.1.3.tar.gz
# Cd postgresql-7.1.3
#./Configure -- prefix =/usr/local/pgsql
# Make
# Make install
# Chown-r postgre. postgre/usr/local/pgsql

# Vi ~ Postgre/. bash_profile
Add:

Pglib =/usr/local/pgsql/lib
Pgdata = $ home/Data
Path = $ path:/usr/local/pgsql/bin
Manpath = $ manpath:/usr/local/pgsql/man
Export pglib pgdata path manpath

Log On As an ipvs user,
# Su-postgre
Create a database directory:
$ Mkdir data

Start the database engine:
[Postgre @ WWW postgre] $ initdb
[Postgre @ WWW postgre] $ postmaster-I-d ~ /Data &
In this way, PostgreSQL uses a database located in/usr/local/pgsql/data to allow Internet users to connect (-I) and run it in the background.
At this step of installation, the database is running

Create databases and tables
$ Createdb mydb

Then enter/contrib/dblink
Make/make install
// After success, start pg_ctl restart
Run
Psql-F dblink. SQL-D database-u User Name

Question 2:
Pgsql = # select dblink_connect ('host = localhost user = pgsql Password = ');
Dblink_connect
----------------
OK
(1 row)
This function is used to establish a connection to a remote database.

We can insert a record in a remote database as follows:
Pgsql = # select dblink_exec ('insert into student values (\ 'linux _ prog \ ', \ '2017 \')');
Dblink_exec
-------------------
Insert 22516276 1
(1 row)

Now we can retrieve the insert record:
Pgsql = # select * From dblink ('select * from student ') as student (name varchar (100), pass varchar (100 ));
Name | pass
------------ + -------
Linux_prog | 12345
(1 row)

How is it? The insert record is already in.

Question 3
I feel like
PostgreSQL has stricter permission settings than orcale ..