As a data analyst, you are on a journey. Think about all the data that is being generated each day and that is available in an organization, from transactional data in a traditional database. For example, today's retail businesses collect and store massive amounts of data that track the items you browsed and purchased, the pages you've visited on their site

 INTRODUCTION TO EXCEL

 Excel sheet consist of cells in which you can enter and calculate data. The cells are organized into columns and rows.

 Excel is used for the followings; Data entry, data management, accounting, financial and data analysis, charting and

graphing, time management etc

(i) COLUMNS--------Are alphabet line (A—XFD) There are 16,384 columns in a single cell

(II)    ROWS---------Are numeric line (1---more than 1 million).

Functions is built set of instructions. (In functions excel gives a set of instructions to arrive at the answer).

The set of instruction given by excel to arrived at the answer is called function syntax.

DATA CLEANING

What is data cleaning?

Data cleaning, also known as data cleansing, is the process of detecting and correcting errors or inconsistencies in a dataset. This can include tasks like removing duplicate records, removing etral rows, removing unprintable characters, correcting spelling mistakes, standardizing date formats, and so on.

Introduction to SQL:

SQL (Structured Query Language) is a programming language designed for managing and querying relational databases. It provides a standardized way to interact with databases.

The basic structure of an SQL query involves: 

Querying Data

Bringing a file with the ".bak" extension into SQL Server;

First, you'll need to log into SQL Server Management Studio (SSMS) and connect to the database server. Next, right-click on the database you want to import the ".bak" file into and a dialogue box will appear, choose device and click 3 dots at the right side of device to add file and browse to the location of the file. Then select the file name and click Ok.

NOTE; It is advisable you save the ".bak file" on a local disk(c) insed users folder.

An operator is a reserved word or a character that is used to query our database in a SQL expression. To query a database using operators, we use a WHERE clause. Operators are necessary to define a condition in SQL, as they act as a connector between two or more conditions.

LIKE OPERATORS (WILD CARD % %) A wild card is used to substitute one or more characters in a string. They are used with Like operator. The Like operator is used in a WHERE clause to search for a specific pattern in a column.

Temporary Table (TempTable)

A temporary table is a base table that is not stored in the database but instead exists only while the database session in which it was created is active. At first glance, this may sound like a view, but views and temporary tables are rather different: ▪ A view exists only for a single query.

Tableau Bins are equal-sized containers that store data values that correspond to or fit within the Bin Size. Tableau Bins divide a set of data into groups of equal intervals or sizes, resulting in a systematic distribution of data.

"Table Designer" feature in SQL Server Management Studio! That's a very useful feature, especially if you're new to SQL. It allows you to visually create a table, instead of writing the "CREATE TABLE" command. It's a quick and easy way to create tables, but it's not as powerful as writing the command yourself.

What is Power BI?

Power BI is a collection of software services, apps, and connectors that work together to turn your unrelated sources of data into coherent, visually immersive, and interactive insights.

Power BI Desktop also includes the Power Query Editor, which opens in a separate window. In Power Query Editor, you can build queries and transform data, then load the refined data model into Power BI Desktop to create reports. Use Power Query Editor to connect to one or many data sources, shape and transform the data to meet your needs, then load that model into Power BI Desktop.

A Data model is a collection of tables and relationships that can be used to create a report.

Is techniques use in creating relationship between two or more tables.

Modeling data is about establishing and maintaining relationships so that you can effectively visualize the data in the form that your business requires.

The tables in a data model are called “Fact” tables and “Dimension” table.

A fact table contains quantitative information like sales transactions or customer purchase While a dimension table contains descriptives information like customer demographics or product categories.