The TypeScript dictionary type allows you to store data in a key-value format. TypeScript provides the dictionary functionality through the Map data type. In this post, we will learn about TypeScript Dictionary Type (Map) with multiple examples. Introduction The map data type allows you to store data in key-value pairs. …
The array in TypeScript allows you to store a collection of values of a single data type. TypeScript provides a number of functions to do various operations on an array. In this post, we will learn about the TypeScript array and its functions. Syntax Below is the syntax for declaring …
A typescript array allows you to hold elements of different types, and a map allows you to store key-value pairs of items. One of the common requirements in a typescript project is to convert an array to a map. In this post, we shall learn different ways to convert an …
A type alias in TypeScript is used for giving new names to existing data types. Type aliases can be used with a single data type, but their primary application is with union data types, which allow a single variable to contain two or more data types. We will learn how …
In order to connect to a PostgreSQL database, you must have a PostgreSQL user. A user in PostgreSQL has a username and a password to connect to the PostgreSQL server. Additionally, you can grant him various permissions to carry out his work. It is also possible to form a user …
PostgreSQL provides the psql utility to connect to and communicate with PostgreSQL databases. psql provides a command-line interface for connecting to a PostgreSQL instance. Every installation of the PostgreSQL server comes with psql, which is the default client for interacting with the server. To work with PostgreSQL databases, psql offers …
PostgreSQL provides various date and time functions. One of the common functions is CURRENT_TIMESTAMP. PostgreSQL provides the CURRENT_TIMSTAMP function to show the current timestamp. The timestamp includes both the date and time information, along with time zone information. We can use the CURRENT_TIMSTAMP function in select queries and insert or …
PostgreSQL is an open-source relational database system. One of the common tasks of a PostgreSQL developer is to show all tables from a database. PostgreSQL provides two ways to list all tables from a database. PSQL Command Line Method PSQL allows us to interact through a terminal-based front-end. To list …
A column can be removed from PostgreSQL once it has been created. The ALTER TABLE command can be used to delete a column. You must specify both the name of the table and the desired column alongside the alter table command to delete a column in PostgreSQL. Syntax The syntax …
PostgreSQL offers a range of data types. Use ALTER TABLE command to alter column type to a different data type. The ALTER TABLE command syntax. Alter Column Type Example (Change Type Integer to VARCHAR) For example, we have the “item_type” column, which is of the integer data type. In this …