Change data types examples in Power Query

When to use this Power Query pattern

Use this pattern when the same data preparation step needs to happen every time a file, table or report refreshes.

Syntax or pattern

Table.TransformColumnTypes(Source, {{"OrderDate", type date}, {"Sales", type number}})

Typical UI steps

Open Power Query Editor.
Select the relevant column or query.
Apply the transformation from the ribbon or formula bar.
Review the generated step.
Check data types and row counts before loading.

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5 practical examples

Use Change data types in a sales report

This example shows how to use Change data types when preparing a sales report.

Table.TransformColumnTypes(Source, {{"OrderDate", type date}, {"Sales", type number}})

Use this pattern when the sales report needs a repeatable transformation instead of manual cleanup.

Use Change data types in a customer list

This example shows how to use Change data types when preparing a customer list.

Table.TransformColumnTypes(CleanSource, {{"OrderDate", type date}, {"Amount", type number}})

Use this pattern when the customer list needs a repeatable transformation instead of manual cleanup.

Use Change data types in a inventory export

This example shows how to use Change data types when preparing a inventory export.

Table.TransformColumnTypes(Inventory, {{"OrderDate", type date}, {"Units", type number}})

Use this pattern when the inventory export needs a repeatable transformation instead of manual cleanup.

Use Change data types in a monthly dashboard

This example shows how to use Change data types when preparing a monthly dashboard.

Table.TransformColumnTypes(ReportData, {{"Date", type date}, {"Revenue", type number}})

Use this pattern when the monthly dashboard needs a repeatable transformation instead of manual cleanup.

Use Change data types in a operations tracker

This example shows how to use Change data types when preparing a operations tracker.

Table.TransformColumnTypes(Tracker, {{"OrderDate", type date}, {"Hours", type number}})

Use this pattern when the operations tracker needs a repeatable transformation instead of manual cleanup.

Common mistakes to avoid

Changing types before cleaning text values such as blanks, currency symbols or commas.
Using locale-sensitive conversions without checking date and decimal formats.
Assuming every row can be converted without handling errors.

FAQ

When should I use Change data types in Power Query?

Use Change data types when the transformation should be repeatable every time the data refreshes.

Can I do Change data types from the Power Query interface?

Usually yes. The interface creates the M code for many common transformations, and you can adjust it in the formula bar or Advanced Editor.

Should I edit the M code manually?

Edit M manually when the interface cannot express the pattern clearly, or when you need reusable logic, parameters or cleaner step names.