Postgres and Open Source Experts

SELF JOIN is used in the PostgreSQL database to join a table to itself when tables are created in a hierarchy fashion to apply queries on it.

Create an AWS RDS DB instance from the service dashboard and use PostgreSQL as its engine. Use Endpoint and username in the “psql” command to connect to it.

Create an RDS database with IAM authentication enabled. Attach the IAM role to the EC2 instance and connect to it to generate the SSH key.

LEFT JOIN is used in the PostgreSQL database to return all the records from the left table and matched records from the right table.

In PostgreSQL, RIGHT JOIN is used to merge two tables in the database and return all records of the Right table and only matched records from the left one.

In PostgreSQL, indexes can be created using the CREATE INDEX statement followed by the index name and then providing the table name inside the ON condition.

To create a materialized view in Postgres, execute the CREATE MATERIALIZED VIEW statement along with the AS keyword followed by the base query.

The index can be changed in PostgreSQL using an ALTER INDEX statement containing the name of the index and then adding conditions to be applied to change it.

In PostgreSQL, the nextval() function fetches the next value from the sequence to add the incremented value to the existing value of the sequence.

In PostgreSQL, indexes can be dropped using the DROP INDEX command followed by the index name or names for dropping multiple indexes using a single query.