Postgres and Open Source Experts

In PostgreSQL, the “\d”, “\dv”, “\dv+” commands, “information_schema.views”, etc., are used to list all the views from a database.

In Postgres, the ALTER VIEW command modifies the views’ definition, such as setting the column's default value, changing the view’s owner, renaming a view, etc.

Postgres provides a “CREATE OR REPLACE VIEW” statement to create a new view or replace an existing view's defining query. It allows us to modify the defining query of a view without dropping a view. It defines a new view if the desired view doesn’t exist already or modifies the view’s defining query if it already exists.

This blog explains how to replace the view’s definition using the “CREATE or …

In PostgreSQL, the “\d” command, “\d+” command, “information_schema”, and “pgAdmin” are used to list all columns of a table.

“\List”, “\l”, and “pg_database” is used in SQL Shell to get the database list. While to switch databases in SQL Shell, the “\c” and “\connect” commands are used.

This post demonstrates stepwise instructions for importing CSV to Postgres or exporting Postgres tables to CSV files using pgAdmin.

PostgreSQL allows us to import CSV files to Postgres tables or export Postgres tables to CSV files using SQL Shell (psql). To do that, the “\COPY” command is used.

Postgres provides an INNER JOIN clause to combine the records of multiple tables based on a specific condition/criteria.

Postgres provides a couple of ways to drop all the tables of a Postgres database, such as dropping the complete schema or removing the schema’s tables individually.

In PostgreSQL, the COALESCE() function and the IS NULL operator are used to find and replace the null values with some default values.