Get started with Tableau to Power BI migration

Scan Tableau workbooks to assess how much can be automatically migrated before committing to a conversion.

[analyze]
path         = "C:/Tableau/Workbooks"
output       = "analysis.pdf"
summary_only = false
no_recursion = false

Common commands

cepheus-navis analyze spec.toml                           # Analyze all workbooks
cepheus-navis analyze spec.toml --path Sales.twbx          # Single workbook
cepheus-navis analyze spec.toml -o analysis.pdf            # Save report
cepheus-navis analyze spec.toml --summary-only             # High-level numbers only
cepheus-navis analyze spec.toml --no-recursion             # Top-level folder only

Submit the License Request PDF to navis@cepheusonline.com. The PDF embeds cryptographic fingerprints of your workbooks. Cepheus replies with a license file.

Supported file types

1. Run cepheus-navis analyze and save the License Request PDF
2. Email the PDF to navis@cepheusonline.com
3. Receive a license file back

[verify-license]
license_file = "license.json"
path         = "C:/Tableau/Workbooks"

cepheus-navis verify-license spec.toml

[convert]
path         = "C:/Tableau/Workbooks"
output_dir   = "C:/Output"
license_file = "license.json"

cepheus-navis convert spec.toml
cepheus-navis convert spec.toml --output-dir C:/Output     # Override output

What Navis produces

For each workbook:

How calculations are converted

Every DAX formula Navis produces has been individually tested against actual Tableau output to verify identical results. This isn't approximate translation — it's proven equivalence. If Navis encounters a calculation it cannot convert with proven accuracy, it flags it rather than guessing.

Already have a Power BI conversion — from a competitor tool, hand-coded, or LLM-generated? Consult mode tells you which of your DAX calculations are correct, which have structural issues, and which Tableau calculations are missing from your project. You see the diagnosis; to get the proven DAX, license a conversion.

[consult]
path    = "C:/Tableau/Workbooks/Sales.twbx"
against = "C:/PowerBI/SalesProject.pbip"
output  = "C:/Reports/consult-output"

cepheus-navis consult spec.toml
cepheus-navis consult spec.toml --path Sales.twbx --against ./customer.pbip -o ./report

What the report contains

Verdict types

What you can do with the results

• Fix flagged calculations yourself — you know what's wrong
• License a Navis conversion for the affected workbooks only — get the validated DAX
• License a full-estate conversion if you prefer a clean start

The diagnosis and the cure are sold separately. You have full information to choose your remedy.

Review the PDF report inside the Evidence Capsule for anything flagged:

• Unmapped calculations — formulas without a proven DAX equivalent yet. Clearly marked so you can write the DAX manually.
• Data connections — configure these after import.
• Dashboard actions (filter, URL, highlight) — noted as degradations, need manual recreation.
• Custom images and decorative elements — not transferred.
• Gantt charts — no direct Power BI equivalent; flagged as a degradation.
• Tableau Server/Cloud features — live connections, user filters, etc. need manual reconfiguration.

Nothing is ever silently skipped. If Navis can't convert something, it tells you.

Power BI Project folder

SalesDashboard/
  SalesDashboard.pbip              <-- Entry point
  SalesDashboard.Report/
    definition.pbir
    report.json
  SalesDashboard.SemanticModel/
    definition.pbism
    definition/
      model.tmdl
      database.tmdl
      tables/
        Orders.tmdl                <-- Your measures (DAX) live here
      cultures/
        en-US.tmdl

The .pbip file is your entry point. The .tmdl files in tables/ contain your converted DAX measures — open them in a text editor to review.

Every conversion produces an Evidence Capsule — a ZIP file named WorkbookName_CEC.zip. A tamper-evident record of exactly what was converted and how.

PDF report sections

1. Summary — conversion date, status, counts
2. Worksheets — each worksheet and its Power BI page
3. Measures — every calculation with original Tableau formula and converted DAX
4. Degradations — anything that couldn't be converted, with explanations
5. Data Model — tables, columns, and their data types

Navis can digitally sign the PDF report and Evidence Capsule. Signing is optional — Navis works fine without it.

[convert]
cert_file     = "certificates/cert.pem"
key_file      = "certificates/key.pem"
ca_chain_file = "certificates/ca_chain.pem"

If configured, Navis signs automatically during conversion. If not present, Navis produces unsigned output.

Passphrase-protected keys

# Linux / macOS
export KEY_PASSPHRASE="your-passphrase"

# Windows (Command Prompt)
set KEY_PASSPHRASE=your-passphrase

# Windows (PowerShell)
$env:KEY_PASSPHRASE = "your-passphrase"

Signing output

• WorkbookName_CEC.zip.p7s — the digital signature
• WorkbookName_CEC.zip.sha256 — hash file for independent verification

Verify signed PDFs in Adobe Acrobat Reader via the signature panel.

cepheus-navis audit-report spec.toml                       # Full report
cepheus-navis audit-report spec.toml --workbook SalesDash  # Single workbook

Creates a Markdown report with tables showing every converted calculation, flagged items, and all degradations.

"Workbook not found"

Double-check the file path. Make sure the file ends in .twb or .twbx.

"Invalid TWBX"

The file may be corrupted. Try re-exporting from Tableau Desktop. Ensure it hasn't been renamed from a different format.

"License not found"

Check the license_file path in your spec.toml. Run cepheus-navis verify-license spec.toml to test.

"Checksum mismatch"

The workbook file changed since the license was issued. Avoid opening workbooks in Tableau Desktop between licensing and conversion. Re-run analyze and request a new license.

Some calculations show as "unmapped"

The calculation uses a formula pattern without a proven DAX equivalent yet. Clearly flagged — won't produce wrong results, just won't be auto-converted. Write the DAX manually. Check the Evidence Capsule PDF for details.

Visuals aren't showing data

• Connect your data sources (Navis converts structure, not data)
• Refresh to load data into the model
• Check that column names match what the converted model expects

A visual looks different

• Some Tableau visuals don't have an exact Power BI equivalent (e.g. Gantt charts)
• Check the PDF report for degradation notes about that visual
• Adjust the visual type or configuration after import

If you run into an issue not covered here, contact navis@cepheusonline.com with the License Request PDF and/or Evidence Capsule ZIP.