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PostgreSQL Primary Key - A Complete Guide

To create a primary key in Postgres, the user must specify the “PRIMARY KEY” keyword along with the name of the targeted column.

How Do I Count Unique Values in PostgreSQL?

In PostgreSQL, the DISTINCT clause can be used with the COUNT() function to count only unique/distinct values of a table.

PostgreSQL Foreign Key With Practical Examples

Foreign keys allows us to link the data of one table to others. The table referencing the foreign key is known as child table, while the table referenced by the foreign key is known as parent table.

How to Use EXCEPT Operator in PostgreSQL?

In PostgreSQL, EXCEPT returns the rows that exist in the result set of the first SELECT query but not in the result set of the second SELECT query.

How to Use Check Constraint in PostgreSQL?

CHECK constraints in PostgreSQL allow us to specify Boolean conditions for inserting or updating values in one or more columns.

PostgreSQL SERIAL- How to Create Auto-increment Columns

PostgreSQL offers a Pseudo-type known as SERIAL. It allows Postgres users to create auto-incremented columns in a table. Using SERIAL, you can create a sequence of integers.

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.