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PostgreSQL TEXT VS VARCHAR Data Types

In Postgres, the TEXT data type accepts unlimited characters, while the behavior of the VARCHAR data type depends on its length parameter.

PostgreSQL Character Data Types: CHAR, VARCHAR, and TEXT

PostgreSQL provides several data types to work with the character/textual data, such as CHAR, TEXT, and VARCHAR. All these data types differ in length.

PostgreSQL TEXT Data Type With Examples

The TEXT data type is one of the character data types in PostgreSQL that is used to store an unlimited number of characters. It is used to create variable-length strings.

How to Use REGEXP_REPLACE Function in PostgreSQL

PostgreSQL provides the REGEXP_REPLACE function to replace, and remove any strings, substring, digits, and characters using the regular expression.

How to Concatenate Strings in PostgreSQL

In PostgreSQL, the “||” operator and a built-in function named “CONCAT()” are used to concatenate multiple strings, characters, etc.

How to Use RETURNING Clause in PostgreSQL

In Postgres, the “RETURNING” clause is used with the INSERT, DELETE or UPDATE queries to retrieve the newly inserted, deleted, or updated data.

How to Show Databases in PostgreSQL

In PostgreSQL, the “\l” statement and “pg_databases” catalog are used to show the list of databases. Use the “\l+” command to show databases with more details.

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.