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How to Use ENUM_FIRST() Function in PostgreSQL

The ENUM_FIRST() is a built-in function in Postgres that retrieves the first value of the enum specified by the parameter.

How Does the JSON_BUILD_OBJECT() Function Work in PostgreSQL

The JSON_BUILD_OBJECT() function is used to create and retrieve a JSON object from a variadic parameter list of key-value pairs.

How to Use JSON_BUILD_ARRAY() Function in PostgreSQL

The JSON_BUILD_ARRAY() is a built-in JSON function that creates and retrieves a JSON array of different types from a variadic parameter list.

How to Use the ARRAY_TO_JSON() Function in PostgreSQL

The array_to_json() is a built-in JSON function that accepts a SQL array as an argument and converts it into a JSON array.

How to Exit Postgres' Command Line Utility (SQL Shell)

In PostgreSQL, various methods are used to exit the Postgres command line utility, such as the “\q” or “\quit” commands, and “CTRL + C”, “CTRL + D”, or “CTRL + Z” shortcut keys.

How to Include Multiple Postgres Databases in a Single Docker Container

To include multiple PostgreSQL databases in Docker container, continuously run the “CREATE DATABASE <database-name>” command with different database names.

Understanding PostgreSQL Functions

PostgreSQL provides various sequence functions like SETVAL(), NEXTVAL(), CURRVAL(), and LASTVAL() to work with sequences efficiently.

How to Do Table Inheritance in PostgreSQL

In PostgreSQL, the “table inheritance” allows us to create a hierarchy of tables, where one table(child) can inherit the structure and properties of another (parent) table.

How to Add or Remove a UNIQUE Constraint on Multiple Columns of a Postgres Table

In PostgreSQL, the “UNIQUE” keyword is used with the CREATE TABLE or ALTER TABLE commands to add a unique constraint on single/multiple columns of a new or an already existing Postgres table.

How to Use the DENSE_RANK() Function in PostgreSQL

The DENSE_RANK() function assigns a rank to each row of a partition based on the specified sorting order. It starts ranking from 1 for the first row and increases the rank for each subsequent row.