What is DENSE_RANK? DENSE RANK is a window function in SQL that is used to assign a rank to each row within a result set. The rank assigned to each row is based on the values in one or more columns specified in the ORDER BY clause. The DENSE RANK function is similar to the …
LAG and LEAD are SQL analytic functions that allow you to access data from a previous or subsequent row in a query result set. LAG provides access to a previous row, while LEAD provides access to the following row. For example, imagine you have a table of sales data with columns for date, product, and …
Handling missing values is an essential aspect of any data analysis or data engineering project. The presence of missing values can have a significant impact on the outcome of your analysis and the accuracy of your results. Therefore, it is crucial to give proper attention to handling this. In data engineering problem statements, missing values …
Cleaning and transforming data is an essential aspect of data analysis and Pandas provides a range of tools and methods to perform these tasks efficiently. In this section, you’ll learn how to work with Pandas to clean and transform data, from removing missing values and duplicates, to merging and aggregating data. We’ll demonstrate these techniques …
Numpy is a powerful library for mathematical computing and data manipulation in Python. It provides a robust and efficient array data structure for numerical computing, allowing for vectorized operations and efficient computation of mathematical operations on large datasets. With Numpy, you can perform a wide range of operations including statistical analysis, linear algebra, and signal …
Pandas is a powerful and popular library for data analysis and manipulation in Python. It provides easy-to-use data structures and data analysis tools to handle, clean, and process large datasets. With its rich features, pandas makes it easier to explore, manipulate and transform data, making it the go-to tool for data engineers and data scientists. …
Data manipulation and cleaning is a crucial aspect of data engineering, as it prepares raw data for further analysis and modeling. In Python, there are a variety of libraries and tools available that make this process efficient and effective. With libraries like NumPy, pandas, and Openpyxl, data engineers can perform various operations such as reading …
Tuple A tuple is a built-in data structure in Python that represents an ordered, immutable collection of elements. Here’s an example of how to create a tuple in Python: You can access elements in a tuple using indexing: Sets A set is a built-in data structure in Python that represents an unordered collection of unique …
Understanding data types and variables is a crucial part of programming in any language, including Python. A data type determines what kind of values a variable can hold and how those values can be processed and manipulated. In Python, there are several built-in data types, such as integers, floats, strings, and booleans, as well as …
Setting up a Python environment Let’s setup Python environment. Setting up a Python environment involves installing Python on your computer and configuring it to meet your needs. Here’e step-by-step procedure. Your First Python Script Let’s write every developer’s first (probably) program. Hello, World!
