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How to Join Three Tables in PostgreSQL

PostgreSQL uses the INNER JOIN to get matching results from two or more tables based on the defined join conditions.

How to Get/Check Yesterday’s Date in PostgreSQL

In Postgres, there is no such function that directly retrieves yesterday’s date. However, any Postgres function that returns today’s date can be used with the “-” operator to get yesterday’s date.

How to Uninstall PostgreSQL on CentOS?

To uninstall PostgreSQL from CentOS, execute the “yum remove postgresql-server postgresql-contrib” command.

PostgreSQL SELECT INTO Statement With Examples

In PostgreSQL, the SELECT INTO statement creates a new table, copies data from the original table, and pastes it into the newly created table.

PostgreSQL RANK() Function With Examples

Postgres has a built-in Window function called RANK() that assigns a rank to every single row within a partition.

PostgreSQL Subquery Explained With Examples

A subquery in PostgreSQL is nothing more than a query within another query. It is also called a nested query, inner query, or inner select.

PL/pgSQL Record Types Explained With Examples

In PL/pgSQL, the record types are used to create the variables that can store a complete row/record of a result set.

PostgreSQL ROW_NUMBER() Function With Examples

In Postgres, the “ROW_NUMBER()” function is used with the OVER clause to operate on a set of rows and assigns a unique integer to each row.

Constants in PostgreSQL Explained With Examples

In Postgres, constants are nothing but immutable or unchangeable variables. Once a constant is initialized with a value, it stays the same throughout the program.

PL/pgSQL SELECT INTO Statement - Assign Data to a Variable

PostgreSQL supports a “PL/pgSQL SELECT INTO” statement that assists us in storing the table's data into a specific variable.