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MongoDB provides drivers for connecting databases with various programming languages like Java, Python, JavaScript, and C#. As per official documentation, there is a standard URI (Uniform Resource Identifier) for creating connection through programming. The syntax is, mongodb://username:password@host:port/defaultauthdb If the password has special characters like : / ? # [ ] @ then there will be a problem with the above URL syntax for making connection. To resolve this, Percentage-encoding mechanism can be used in URI, A percent-encoded octet is encoded as a character triplet, consisting of the percent character "%" followed by the two hexadecimal digits representing that octet's numeric value - Wikipedia. Percentage-encoding for / ? # [ ] @ / - %2F ? - %3F # - %23 [ - %5B ] - %5D @ - %40 Sample Passwords Secure@pass567 can be written as Secure%40pass567 URI: mongodb://tom:Secure%40pass567@localhost:27017/demodbname Secre#tig] can be written as Secr

There is a problem with copying website text content by using the Ctrl+C keyboard shortcut in the recent version of Microsoft Edge Browser. The same functionality will work if you right-click using the mouse and select the copy option. This is really annoying for Developers and Web users who frequently uses keyboard shortcuts. There is a workaround for this problem to enable copy using Ctrl+C. Workaround: Edge Settings. Open Microsoft Edge Click on the three dots (…) from the right top corner. Select Settings from the drop-down and click on " Appearance " from the left pane. Disable " Show mini menu when selecting text " from the right pane.

In this post, We will discuss How to connect the Postgres database in both Windows and Ubuntu Operating Systems and will learn some basic Postgres commands. Also, we shall try a set of basic SQL queries for manipulating database Tables. Connecting Postgres Database in Ubuntu sudo -u postgres p postgres Connecting Postgres Database in Windows Just open the psql window from the start menu Display List of Databases in Postgres #\l Connect to Database (Postgres) #\c postgres; You are now connected to database "postgres" as user "user_3y3vmxg6f". Create a Table (e.g. student) create table student (rollno integer , name character ( 200 ), dob date ); CREATE TABLE Adding Primary Key alter table student add constraint student_pk primary key(rollno); ALTER TABLE Display Tables in DB #\dt; List of relations Schema | Name | Type | Owner --------+---------+-------+---------------- public | s

Servlet is a Java technology used for developing Web Applications and managed by a container called a servlet engine. It generates dynamic content and interacts with the client through Request and Response. Servlet extends the functionality of a web server. Java Servlet API is available in javax.servlet package. Web Application Architecture (Three Tier) Presentation Layer Client layer: to view the application) Application Layer Business Logic Layer : interacts with the Database layer and sends required information to the Presentation layer Data Layer The data is stored in this layer. The application layer communicates with the Database layer to retrieve the data Java Servlet Life-Cycle The Java Servlet Life cycle includes three stages, init() : gets invoked is when the servers are fired up service() : the service requests from the client end destroy() : Servlet performs the cleanup activities Creating Dynamic Web Project using Eclipse Download eclipse from th