PostgreSQL – DROP TABLESPACE

In PostgreSQL, the DROP TABLESPACE statement is used to remove a tablespace.

Syntax: DROP TABLESPACE [IF EXISTS] tablespace_name;

Let’s analyze the above syntax:

• First, specify the name of the tablespace that is to be deleted after the DROP TABLESPACE keywords.
• Second, use the IF EXISTS option to handle errors in case the tablespace doesn’t exists.

Note: It is important to note that only tablespace owners or superusers can execute the DROP TABLESPACE statement.

Example:

First, we create a new tablespace named gfg and map it to the C:\data\gfg directory:

CREATE TABLESPACE gfg
LOCATION 'C:\data\gfg';

Now create a database named db_gfg and set its tablespace to gfg: 

CREATE DATABASE db_gfg 
TABLESPACE = gfg;

Now create a new table named test in the db_gfg and set it tablespace to gfg:

CREATE TABLE test (
    ID serial PRIMARY KEY,
    title VARCHAR (255) NOT NULL
) TABLESPACE gfg;

The following statement returns all objects in the gfg tablespace:

SELECT
    table_space.spcname,
    class.relname
FROM
    pg_class class
JOIN pg_tablespace table_space 
    ON class.reltablespace = table_space.oid
WHERE
    table_space.spcname = 'gfg';

This will lead to the following:

Now if you try to drop the gfgtablespace:

DROP TABLESPACE gfg;

This will raise the following error:

As the gfg tablespace is not empty,it is not possible to drop the tablespace. Now, login to the Postgres database and drop the db_gfg database:

DROP DATABASE db_gfg;

Now delete the gfg tablespace again:

DROP TABLESPACE gfg;

Now check for the tablespace using the below command to verify:

\db+

Output: