flowchart TD
A[Connect to Data] --> B[File Sources\nExcel, CSV, JSON, PDF]
A --> C[Database Sources\nSQL, BigQuery, Snowflake]
A --> D[Published Sources\nTableau Server or Cloud]
B --> E[Data Source Page\nConfigure Joins and Unions]
C --> E
D --> F[Direct to Worksheet\nno Data Source Page]
E --> G{Connection Type?}
G --> H[Live\nReal-time queries]
G --> I[Extract .hyper\nFast in-memory]
H --> J[Worksheet]
I --> J
style A fill:#e3f2fd,stroke:#1976D2
style G fill:#fff9c4,stroke:#F9A825
style J fill:#e8f5e9,stroke:#388E3C
13 Connecting to Data and Measure Names
Every Tableau workbook begins with a data connection. This chapter covers the complete data connection workflow, connecting to files, databases, and published data sources; configuring live vs. extract connections; understanding how Tableau handles wide (column-heavy) datasets using Measure Names and Measure Values; and managing data source metadata. You will also learn how to use Measure Names and Measure Values, two special auto-generated fields that unlock a class of multi-measure charts that would otherwise require complex data reshaping.
13.1 Data Connection Types
Tableau can connect directly to a wide range of file formats without any additional drivers or setup:
| File Type | Extension | Notes |
|---|---|---|
| Microsoft Excel | .xlsx, .xls | Connects to any sheet or named range |
| Text / CSV | .csv, .txt, .tsv | Configurable delimiters and character encoding |
| JSON | .json | Tableau parses nested JSON automatically |
| Tableau extracts tabular data from PDF tables | ||
| Spatial files | .shp, .kml, .geojson, .topojson | For geographic analysis |
| Statistical files | .sas7bdat, .rda, .sav | SAS, R, and SPSS datasets |
| Google Sheets | URL | Direct connection via Tableau’s Google Sheets connector |
Connecting to Excel: 1. On the Start Page, click Microsoft Excel under Connect > To a File. 2. Navigate to the file and click Open. 3. On the Data Source Page, drag the desired sheet(s) from the left panel to the canvas. 4. Configure joins if multiple sheets are needed.
Tableau connects to over 80 database types and cloud platforms via native connectors. Common connectors include:
| Category | Examples |
|---|---|
| Cloud data warehouses | Snowflake, Google BigQuery, Amazon Redshift, Azure Synapse |
| Enterprise databases | Microsoft SQL Server, Oracle, IBM Db2, SAP HANA |
| Open-source databases | MySQL, PostgreSQL, SQLite |
| Cloud platforms | Salesforce, Google Analytics, Marketo |
| Web data connectors | Any REST API with a Web Data Connector (WDC) |
Connecting to a database: 1. On the Start Page, click the relevant connector under Connect > To a Server. 2. Enter the server address, port, database name, and authentication credentials. 3. Click Sign In. The Data Source Page opens with the available schemas and tables. 4. Drag tables to the canvas to create the data model.
[Insert screenshot of the SQL Server connection dialog showing server name, database, and authentication fields]
A published data source is a reusable, governed data connection that has been published to Tableau Server or Tableau Cloud by a data steward. Connecting to a published data source (rather than raw data) ensures all analysts are working from the same certified, clean dataset with consistent field names and calculated fields.
Connecting to a published data source: 1. On the Start Page, click Tableau Server or Tableau Cloud under Connect > To a Server. 2. Sign in with your credentials. 3. Browse or search for the published data source by name. 4. Click Connect. The workbook opens directly to a new worksheet (no Data Source Page, the data model is already configured in the published source).
13.2 Live vs. Extract Connections
A live connection queries the database directly every time the view is updated, when you drag a field, apply a filter, or change a parameter. The data in the view is always current as of the latest database state.
When to use live connections: - The data changes frequently and the dashboard must reflect near-real-time data. - The database is fast enough to respond within 2–3 seconds (acceptable for interactive use). - Data volume is manageable within the database’s query performance limits.
Disadvantage: Every interaction triggers a database query. On slow connections or large databases, this creates unacceptable latency.
An extract imports a snapshot of the data into Tableau’s in-memory columnar engine (the Hyper format, .hyper file). All queries run against the local Hyper file rather than the remote database, delivering dramatically faster performance.
When to use extracts: - The database is slow or has limited connectivity. - You need to work offline (e.g., on a plane or at a client site without VPN). - You are aggregating or pre-filtering a very large dataset. - You want to share the workbook as a self-contained .twbx file.
Creating an extract: 1. On the Data Source Page, click the Extract radio button (top right). 2. Optionally click Edit to configure extract filters (limit to specific date range), aggregation (pre-aggregate to reduce file size), or row count sampling. 3. Click the first worksheet tab. Tableau prompts you to save the extract as a .hyper file. 4. On Tableau Server, schedule extract refreshes via the Server’s schedule management interface.
[Insert screenshot of the Data Source Page showing the Live/Extract radio buttons, with Extract selected and the Edit button visible]
Rather than refreshing the entire extract every day (a full refresh), configure an incremental refresh that only appends new rows since the last refresh. This is dramatically faster for large datasets.
To configure: in the Extract edit dialog, tick Incremental Refresh and select the date or integer field that identifies new records (e.g., Order Date or Record ID). Tableau compares the field value in the existing extract against the source and appends only new rows.
13.3 The Data Source Page: Detailed Navigation
The Data Source Page is where you define the structure of the data that feeds your worksheets. Key operations:
Renaming fields: Double-click any column header in the data grid to rename it. Rename fields to use business-friendly names (e.g., rename cust_id to Customer ID, rev_usd to Revenue (USD)). These renamed fields appear in the Data pane in every worksheet.
Hiding fields: Click the small arrow on a column header and select Hide. Hidden fields do not appear in the Data pane, reducing clutter. They are still available for joins but not visible to worksheet builders.
Changing data types: Click the data type icon (Abc for string, # for number, calendar for date) above any column to change its type. Common use: a numeric field like Zip Code must be changed from Number to String to prevent Tableau from summing postal codes.
Splitting fields: For fields that contain multiple values separated by a delimiter (e.g., “New York, USA”), right-click the column header and select Split to automatically separate into individual columns.
Pivoting columns to rows: When data is in “wide” format (one column per measure, e.g., Jan, Feb, Mar as separate columns), select those columns, right-click, and select Pivot to convert them to a single “Month” column and a “Value” column, the tidy format Tableau works best with.
Wide format (what many Excel spreadsheets use):
| Region | Jan Sales | Feb Sales | Mar Sales |
|---|---|---|---|
| East | 12000 | 14000 | 11000 |
Long format (what Tableau works best with):
| Region | Month | Sales |
|---|---|---|
| East | Jan | 12000 |
| East | Feb | 14000 |
| East | Mar | 11000 |
Steps in Tableau: 1. On the Data Source Page, hold Ctrl and select all the month columns (Jan Sales, Feb Sales, Mar Sales). 2. Right-click the selected headers and choose Pivot. 3. Tableau creates two new columns: Pivot Field Names (containing “Jan Sales”, “Feb Sales”, etc.) and Pivot Field Values (containing the sales numbers). 4. Rename Pivot Field Names to “Month” and Pivot Field Values to “Sales”.
[Insert screenshot of the Data Source Page before and after pivoting, showing the column selection and the resulting long-format data grid]
13.4 Measure Names and Measure Values
Measure Names and Measure Values are two special auto-generated fields that Tableau creates automatically for every data source. They appear at the bottom of the Dimensions and Measures sections in the Data pane.
- Measure Names, A dimension containing the names of all measures in your data source as string values (e.g., “Sales”, “Profit”, “Quantity”, “Discount”).
- Measure Values, A measure containing the aggregated values of all measures simultaneously, determined by whatever subset of measure names is filtered or in context.
Together, these two fields allow you to plot multiple measures on the same axis simultaneously, something that is otherwise impossible in Tableau’s standard interface, where each measure gets its own axis.
Tableau automatically places Measure Names on Rows/Columns and Measure Values on the opposite shelf whenever you drag two or more measures to the same axis. You will recognise this pattern: - Both pills appear on the shelves. - A Measure Values card appears in the Marks card area, showing all selected measures with individual mark property controls. - A Measure Names filter appears in the Filters shelf, allowing you to control which measures are displayed.
[Insert screenshot of the Tableau worksheet interface showing Measure Names on Rows, Measure Values on Columns, and the Measure Values marks card with multiple measure entries]
Goal: Display Sales, Profit, and Quantity side by side for each Sub-Category in a single bar chart.
- Drag
Sub-Categoryto the Rows shelf. - Hold Ctrl and drag
Sales,Profit, andQuantityto the Columns shelf simultaneously, Tableau automatically creates a Measure Names/Measure Values view with three panels. - Alternatively: drag
Measure Valuesto Columns andMeasure Namesto the Colour shelf, this creates a grouped bar chart with one colour per measure. - In the Filters shelf, a
Measure Namesfilter appears. Open it and ensure only the desired measures are checked. - Format each measure independently using the Measure Values card in the Marks area.
[Insert screenshot of a grouped bar chart with Sub-Category on Rows and three measures (Sales, Profit, Quantity) as coloured bar groups, with Measure Names on Colour]
The most powerful use of Measure Names is creating a small multiples layout where each panel shows a different measure, allowing direct visual comparison of multiple KPIs with identical axis structures.
- Drag
Order Date(Month, continuous) to the Columns shelf. - Drag
Measure Valuesto the Rows shelf. - Drag
Measure Namesto the Rows shelf alongsideMeasure Values. - Open the
Measure Namesfilter and select only the measures you want (e.g., Sales, Profit, Quantity). - Tableau creates three rows of line charts, one per measure, all sharing the same time axis.
- Right-click each Y-axis and select Edit Axis > Independent axis ranges to allow each panel to scale to its own data range.
[Insert screenshot of a three-panel small multiples line chart: one row each for Sales, Profit, and Quantity, all sharing the same X-axis time series]
One limitation of the Measure Names/Measure Values approach is that all measures must share the same mark type, colour scheme, and axis format, you cannot independently colour the Sales bar blue and the Profit bar green within the same Measure Values axis. For fully independent formatting per measure, use a dual-axis chart (for two measures) or a small multiples layout with individual worksheets per measure assembled on a dashboard (for three or more measures).
13.5 Data Source Metadata Management
Well-organised Data pane fields make workbooks faster to build and easier for colleagues to use. Best practices:
Rename fields: Double-click any field in the Data pane to rename it. Use business-friendly, unambiguous names. Rename immediately after connecting, before any worksheets reference the original names.
Create folders: Right-click in the Data pane and select Create Folder. Drag related fields into the folder (e.g., “Date Fields”, “Financial Metrics”, “Customer Dimensions”). This is especially valuable when connecting to a database table with dozens of columns.
Hide irrelevant fields: Right-click any field and select Hide. Hidden fields are excluded from the Data pane view but remain accessible via Show Hidden Fields if needed.
Add field descriptions: Right-click a field and select Default Properties > Comment to add a description. This description appears in the tooltip when teammates hover over the field in the Data pane, invaluable for shared published data sources.
Set default aggregation: Right-click a measure and select Default Properties > Aggregation to change from SUM (the default) to AVG, MAX, or another aggregation. The field will use this aggregation by default whenever dragged to a shelf.
13.6 Summary
| Concept | Description | Key Access |
|---|---|---|
| File connection | Connect to Excel, CSV, JSON, spatial files | Start Page > To a File |
| Database connection | Connect to SQL, BigQuery, Snowflake, etc. | Start Page > To a Server |
| Published data source | Reusable governed connection on Server/Cloud | Start Page > Tableau Server |
| Live connection | Real-time database queries | Data Source Page > Live radio button |
| Extract (.hyper) | Fast in-memory snapshot | Data Source Page > Extract radio button |
| Incremental refresh | Append only new rows to extract | Extract Edit dialog > Incremental Refresh |
| Pivot | Convert wide format to long format | Select columns > Right-click > Pivot |
| Measure Names | Auto-generated dimension of measure names | Data pane (bottom of Dimensions) |
| Measure Values | Auto-generated measure containing all measure values | Data pane (bottom of Measures) |
| Field renaming | Business-friendly names in Data pane | Double-click field in Data pane |
The single most impactful data connection habit is to rename and organise all fields immediately after connecting to a new data source, before building any worksheets. The five minutes spent creating folders, renaming cryptic database column names, and hiding irrelevant fields will save hours of confusion for you and every colleague who uses the workbook after you. Treat the Data Source Page as the foundation of your workbook: a clean, well-organised foundation produces better work faster.