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This is the Education section of the Command Prompt Website. Here you will find blogs specifically about how to use Postgres and related technologies.

PostgreSQL NOT NULL Constraint With Examples

The NOT NULL constraint ensures that the column accepts only non-null values. In Postgres, the CHECK constraint can be used as an alternative to the NOT NULL.

How to Use ABS() Function in PostgreSQL

PostgreSQL offers a built-in mathematical function named ABS() that takes an expression as an argument and retrieves an absolute value for the specified number.

How to Round Numbers in PostgreSQL

PostgreSQL offers several built-in math functions such as ROUND(), CEIL(), and FLOOR() to round a number up to specific decimal places.

How to Optimize Postgres Performance Using ANALYZE and VACUUM Commands

PostgreSQL offers several commands to optimize, improve or maintain the health of a database, tables, etc., such as ANALYZE and VACUUM commands.

How to Use VACUUM Command in PostgreSQL

In Postgres, VACUUM is a command-line utility that vacates the space engaged by obsolete records, tuples, etc. It optimizes the performance of the Postgres databases, records, etc.

How to Use MOD() Function in PostgreSQL?

The MOD() function is one of the built-in mathematical functions in Postgres that perform the modulo operation on two numbers and retrieves the remainder.

How to Use ANALYZE Command in PostgreSQL

PostgreSQL offers a convenient command named ANALYZE that collects the statistics about a database, table, or table’s columns for the query planner.

PostgreSQL Column Alias With Practical Examples

In PostgreSQL, column aliases are temporary alternative names assigned to columns. The aliases are temporary alternatives, so they exist temporarily during the query’s execution.

How to Find Duplicate Rows in PostgreSQL

PostgreSQL offers several built-in functions to find duplicate rows/records from a table, such as ROW_NUMBER() and COUNT().

PostgreSQL ISNULL Function With Examples

PostgreSQL doesn’t support the ISNULL function. To achieve the functionality of the ISNULL function in Postgres, COALESCE function and CASE expressions are used.