Tecnolynx Interview Questions and Answers

SQL query to select 2nd highest salary

• Use ORDER BY and LIMIT to select the highest salary

• Use a subquery to exclude the highest salary and select the next highest

• Example: SELECT salary FROM employees ORDER BY salary DESC LIMIT 1,1

=== checks for both value and type equality, while == checks for value equality only.

• === is stricter than == in terms of type checking

• === returns true only if both operands are of the same type and have the same value

• == performs type coercion, which can lead to unexpected results

• For example, '5' == 5 will return true, but '5' === 5 will return false

Data is passed from parent to child in Vue.js using props.

• Parent components can pass data to child components by binding values to props.

• Props are declared in the child component and can be accessed using this.props.

• Data can be passed as a string, number, boolean, object, or array.

• Parent components can also pass data dynamically by using v-bind directive.

• Child components can use the passed data in their template or met

GET is used to retrieve data from a server while POST is used to submit data to a server.

• GET requests are read-only and do not change the state of the server

• POST requests can change the state of the server

• GET requests can be cached while POST requests cannot

• GET requests have a limit on the amount of data that can be sent while POST requests do not

• GET requests are visible in the URL while POST requests are not

React Hooks are functions that allow functional components to use state and lifecycle methods.

• Hooks were introduced in React 16.8

• useState() is a hook that allows functional components to use state

• useEffect() is a hook that allows functional components to use lifecycle methods

• useContext() is a hook that allows functional components to use context

• useReducer() is a hook that allows functional components to use a reducer f