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PostgreSQL JSON_AGG() Function By Practical Examples

In PostgreSQL, the JSON_AGG() function is used to combine multiple values into a single JSON array. The return type of the JSON_AGG() function is JSON.


Postgres’ ALTER DATABASE command modifies the already existing databases, such as renaming a database, modifying the database attributes, changing the database ownership, etc.

How to Set Windows PATH for Postgres Tools

To set Windows PATH for Postgres tools, open System Properties > “Environment Variable” > “Path” variable > “Edit..” button > “NEW” button > specify Postgres bin directory’s path > hit the “OK” button.

Different Methods to Copy or Clone a Table in PostgreSQL

In Postgres, different commands, such as CREATE TABLE AS SELECT, CREATE TABLE AS TABLE, etc. are used to duplicate a table with or without data.

How to Start, Stop, or Restart the PostgreSQL Server?

There are various ways to start, stop, or restart the Postgres server on Windows, such as using the “net start” command, “pg_ctl” utility, or “services” manager.

How Do I Set/Change the Default Schema in PostgreSQL

A schema in database management systems represents a set of rules that regulate/handle a database. It is a logical structure that holds various database objects like views, tables, indexes, sequences, etc. In Postgres, “public” is a Default schema. So, by default, Postgres users can access the "public" schema and create objects in it, such as views, tables, etc.

The SET SEARCH_PATH command, however, allows a user to set any other …

How to Create a Copy of a Database in PostgreSQL

In PostgreSQL, use the CREATE DATABASE command along with the “WITH TEMPLATE” parameter to copy or clone a database.

Working With PostgreSQL JSON Data

PostgreSQL supports a JSON data type that stores the data in the form of key-value pairs. It is an open standard format for transferring data between a server and web apps.

PostgreSQL Conditional Expressions - Explained With Examples

In PostgreSQL, conditional expressions are used to select one of the multiple values based on the Boolean condition.

How to Query JSON Column in Postgres

Postgres supports a couple of native JSON operators to query the data from a JSON column. These operators include a short arrow “->” and a long arrow “->>”.