Tableau Fundamentals

Tableau là tool visualization mạnh nhất thế giới, được dùng bởi Fortune 500 companies. Bài này sẽ guide bạn từ cài đặt đến tạo visualization đầu tiên.

🎯 Mục tiêu

Cài đặt và setup Tableau
Hiểu Tableau interface
Connect và prepare data
Tạo các charts cơ bản
Build dashboard đầu tiên

1. Tableau Products Overview

1.1. Tableau Family

Product	Purpose	Cost
Tableau Desktop	Create visualizations	$70/mo
Tableau Public	Free version (public data only)	Free
Tableau Server	Share internally	Enterprise
Tableau Online	Cloud sharing	$42/user/mo
Tableau Prep	Data preparation	Included

1.2. Installation

For learning: Tableau Public (Free)

Download từ public.tableau.com
Install và create account
Limitation: Saves to public cloud only

For work: Tableau Desktop

Download trial từ tableau.com
14-day free trial
Full features

2. Tableau Interface

2.1. Start Page

Text

1┌─────────────────────────────────────────────────────────────┐
2│  CONNECT                    │  OPEN                        │
3│  ─────────────────          │  ─────────────────           │
4│  To a File                  │  Recent Workbooks            │
5│  • Excel                    │  • Sales_Dashboard.twb       │
6│  • Text file                │  • Marketing_Report.twb      │
7│  • JSON                     │                              │
8│  • More...                  │  Sample Workbooks            │
9│                             │  • Superstore                │
10│  To a Server                │  • World Indicators          │
11│  • Tableau Server           │                              │
12│  • MySQL                    │  DISCOVER                    │
13│  • PostgreSQL               │  ─────────────────           │
14│  • More...                  │  Viz of the Day              │
15└─────────────────────────────────────────────────────────────┘

2.2. Workspace

Text

1┌─────────────────────────────────────────────────────────────────────────┐
2│ File  Data  Worksheet  Dashboard  Story  Analysis  Map  Format  Server │
3├───────────────┬─────────────────────────────────────────────────────────┤
4│ DATA          │                                                         │
5│ ┌───────────┐ │                                                         │
6│ │ Tables    │ │                                                         │
7│ │ └Orders   │ │           CANVAS (Drop fields here)                    │
8│ │ └Customers│ │                                                         │
9│ │ └Products │ │                                                         │
10│ └───────────┘ │                                                         │
11│               │                                                         │
12│ DIMENSIONS    │                                                         │
13│ ┌───────────┐ │   ┌─────────────────────────────────────────────────┐  │
14│ │ Category  │ │   │                                                 │  │
15│ │ Region    │ │   │           Your visualization                    │  │
16│ │ Segment   │ │   │           appears here                          │  │
17│ │ Ship Mode │ │   │                                                 │  │
18│ └───────────┘ │   └─────────────────────────────────────────────────┘  │
19│               │                                                         │
20│ MEASURES      │                                                         │
21│ ┌───────────┐ │                                                         │
22│ │ Sales     │ │                                                         │
23│ │ Profit    │ │   ┌──────────────────────────────────────────┐         │
24│ │ Quantity  │ │   │ Columns:                                 │         │
25│ │ Discount  │ │   │ Rows:                                    │         │
26│ └───────────┘ │   └──────────────────────────────────────────┘         │
27├───────────────┴─────────────────────────────────────────────────────────┤
28│ [Sheet 1] [Sheet 2] [+] │ [Dashboard 1] [Story 1]                      │
29└─────────────────────────────────────────────────────────────────────────┘

2.3. Key Terms

Term	Definition
Dimension	Categorical data (Region, Category, Date)
Measure	Numeric data (Sales, Profit, Quantity)
Rows/Columns	Shelves định vị data
Marks	Visual elements (bars, lines, points)
Filters	Limit data displayed
Pages	Animation/stepping through data

3. Connecting to Data

3.1. Data Source Page

Text

1┌─────────────────────────────────────────────────────────────┐
2│ Connections           │  Sheets                            │
3│ ────────────────      │  ─────────────────                 │
4│ ● Sample-Superstore   │  □ Orders         1000 rows        │
5│   (Excel)             │  □ People         4 rows           │
6│                       │  □ Returns        296 rows         │
7├───────────────────────┴────────────────────────────────────┤
8│                                                             │
9│  Drag tables here to relate them                           │
10│                                                             │
11│  ┌─────────┐                                               │
12│  │ Orders  │                                               │
13│  └─────────┘                                               │
14│                                                             │
15├─────────────────────────────────────────────────────────────┤
16│  Preview: (first 1000 rows)                                │
17│  ───────────────────────────────────────                   │
18│  Row ID | Order ID | Order Date | Ship Date | ...          │
19│  1      | CA-2021  | 2021-01-03 | 2021-01-07 | ...         │
20│  2      | CA-2021  | 2021-01-04 | 2021-01-08 | ...         │
21└─────────────────────────────────────────────────────────────┘

3.2. Supported Data Sources

Files:

Excel (.xlsx, .xls)
Text files (.csv, .txt)
JSON
PDF (tables)

Databases:

MySQL, PostgreSQL, SQL Server
Google BigQuery
Snowflake
Amazon Redshift

Cloud Apps:

Google Sheets
Salesforce
Google Analytics

3.3. Data Prep Basics

Text

1Right-click field → Options:
2├── Rename
3├── Change data type (String, Number, Date)
4├── Create calculated field
5├── Create group
6├── Create hierarchy
7├── Hide
8└── Split (for text fields)

4. Building Basic Charts

4.1. Bar Chart - Category Sales

Steps:

Drag Category to Columns
Drag Sales to Rows
Done!

Text

1Sales by Category
2         
3$800K ┤         ████████
4$600K ┤         ████████
5$400K ┤  ████   ████████   ████
6$200K ┤  ████   ████████   ████
7    0 ┼────────────────────────
8      Furniture Office    Technology
9                Supplies

Enhancements:

Sort: Click sort icon in toolbar
Color: Drag Category to Color
Labels: Click Label in Marks card

4.2. Line Chart - Sales Trend

Steps:

Drag Order Date to Columns (auto-becomes YEAR)
Click + on date to expand to Quarter or Month
Drag Sales to Rows

Text

1Sales Over Time
2         
3$100K ┤                    ╱╲
4 $80K ┤              ╱╲   ╱  ╲
5 $60K ┤        ╱╲   ╱  ╲ ╱
6 $40K ┤   ╱╲  ╱  ╲ ╱
7 $20K ┤__╱  ╲╱
8    0 ┼────────────────────────
9      Q1  Q2  Q3  Q4  Q1  Q2  Q3
10         2022          2023

4.3. Scatter Plot - Profit vs Sales

Steps:

Drag Sales to Columns
Drag Profit to Rows
Drag Category to Color

Text

1Profit │                    ●
2       │              ●  ●
3     0 ┼─────────●────────────
4       │     ●   ●
5       │   ●
6       └─────────────────────────
7                           Sales
8         
9● Furniture  ● Office  ● Technology

4.4. Map - Sales by State

Steps:

Double-click State (auto-generates map)
Drag Sales to Color

Text

1┌────────────────────────────────────┐
2│     ▪ ▪    ░░░ ▓▓▓                 │
3│   ▪     ░░░░░░░ ▓▓▓ ▓▓             │
4│    ▪▪▪ ░░░░░░░░░░▓▓▓▓▓▓            │
5│     ░░░░░░░░░░░░░░░ ▓▓▓            │
6│      ░░░░░░░░░░░░░░░ ░             │
7│                                    │
8│  Legend: ▪ Low  ░ Medium  ▓ High   │
9└────────────────────────────────────┘

5. Formatting & Polish

5.1. Marks Card

Text

1┌────────────────┐
2│ Marks          │
3│ ──────────────│
4│ [Automatic ▼] │  ← Chart type
5│ ● Color       │  ← Color encoding
6│ ○ Size        │  ← Size encoding
7│ Abc Label     │  ← Data labels
8│ ◐ Detail      │  ← Add detail
9│ △ Tooltip     │  ← Hover info
10└────────────────┘

5.2. Color Customization

Click Color in Marks
Edit Colors
Choose palette (Sequential, Diverging, etc.)
Adjust stepped colors

5.3. Tooltips

Default tooltip:

Text

1Category: Technology
2Sales: $836,154

Custom tooltip:

Text

1📱 {Category}
2💰 Revenue: ${Sales}
3📈 Growth: {Profit Ratio}%
4Click to see details →

Edit: Worksheet → Tooltip

5.4. Reference Lines

Add context:

Average line
Target line
Trend line
Bands (confidence intervals)

Text

1Analytics Pane → Drag Reference Line to chart

6. Filters

6.1. Filter Types

Type	How to Add	Use
Dimension Filter	Drag to Filters	Include/exclude categories
Measure Filter	Drag to Filters	Range of values
Date Filter	Drag to Filters	Date range
Context Filter	Right-click → Add to Context	Filter that applies first

6.2. Show Filter Control

Text

1Right-click filter → Show Filter
2 
3┌─────────────────┐
4│ Category        │
5│ ☑ Furniture    │
6│ ☑ Office Suppl │
7│ ☐ Technology   │  ← User can toggle
8└─────────────────┘

6.3. Filter Actions

Interactivity:

Click bar → Filter other sheets
Select region on map → Update charts

7. Calculated Fields

7.1. Creating Calculations

Text

1Right-click in Data pane → Create Calculated Field
2 
3Name: Profit Ratio
4Formula: [Profit] / [Sales]

7.2. Common Calculations

SQL

1-- Profit Margin
2[Profit] / [Sales]
3
4-- Year-over-Year Growth
5(SUM([Sales]) - LOOKUP(SUM([Sales]), -1)) / LOOKUP(SUM([Sales]), -1)
6
7-- Running Total
8RUNNING_SUM(SUM([Sales]))
9
10-- Rank
11RANK(SUM([Sales]))
12
13-- IF Statement
14IF [Profit] > 0 THEN "Profitable" ELSE "Loss" END
15
16-- CASE Statement
17CASE [Region]
18  WHEN "East" THEN "Atlantic"
19  WHEN "West" THEN "Pacific"
20  ELSE "Central"
21END

7.3. Level of Detail (LOD) Expressions

SQL

1-- Fixed: Calculate at specific level
2{ FIXED [Category] : SUM([Sales]) }
3
4-- Include: Add dimension to calculation
5{ INCLUDE [Product] : AVG([Discount]) }
6
7-- Exclude: Remove dimension
8{ EXCLUDE [Region] : SUM([Profit]) }

8. Hands-on: Build Sales Dashboard

Step-by-step Project

Data: Sample Superstore (included in Tableau)

Dashboard components:

KPI cards (Total Sales, Profit, Orders)
Sales by Category (bar)
Monthly Trend (line)
Regional Map
Top 10 Products table

Sheet 1: Sales by Category

Text

1Columns: Category
2Rows: SUM(Sales)
3Color: Category
4Sort: Descending
5Labels: Show

Sheet 2: Monthly Trend

Text

1Columns: MONTH(Order Date)
2Rows: SUM(Sales)
3Add: SUM(Profit) as dual axis
4Color: Measure Names

Sheet 3: Regional Map

Text

1Double-click: State
2Color: SUM(Sales)
3Size: SUM(Profit)

Sheet 4: Top Products

Text

1Rows: Product Name
2Columns: SUM(Sales)
3Filter: Top 10 by Sales
4Sort: Descending

Combine into Dashboard

Text

1Dashboard → New Dashboard
2Size: Fixed (1200 x 800)
3 
4Layout:
5┌─────────────────────────────────────────┐
6│ Sales | Profit | Orders (KPI tiles)     │
7├─────────────────┬───────────────────────┤
8│ Sales by        │ Monthly Trend         │
9│ Category        │                       │
10├─────────────────┼───────────────────────┤
11│ Regional Map    │ Top 10 Products       │
12└─────────────────┴───────────────────────┘
13 
14Add Filter actions for interactivity!

📝 Quiz

🎯 Key Takeaways

Drag and drop - Core interaction của Tableau
Dimensions → Categories, Measures → Numbers
Marks card controls visual encoding
Calculated fields enable custom metrics
Dashboards combine sheets for storytelling

🚀 Bài tiếp theo

Power BI Fundamentals - So sánh với Tableau và build reports trong Power BI Desktop!