Power Query in Power BI boasts a multitude of features.

One game-changer? Merging columns from separate tables.

Let's unveil the steps to master this technique.

Setting the Stage

You've got two tables.

Both have some common identifiers but different information.

The goal?

Combine specific columns.

Fire Up Power Query

Access Power Query from Power BI:

• Click on 'Home'.
• Select 'Edit Queries'.

Select the Primary Table

This is the table you want to add data to.

Time to 'Merge Queries'

With your primary table selected:

• Click the 'Home' tab.
• Opt for 'Merge Queries'.

Choosing the Secondary Table

In the 'Merge' dialog:

• Select your secondary table from the dropdown.

Match the Keys

For a successful merge, identify columns in both tables that match.

Typically, these are IDs or names.

Click on the columns to establish the match.

Choose the Merge Type

Several options here, akin to SQL joins:

• Inner, Left Outer, Right Outer, etc. Choose based on the data you need.

Finalizing the Merge

Hit 'OK'.

A new column appears in your primary table, containing data from the secondary table.

Expand the New Column

Click on the small icon in the merged column's header.

Now, select the specific columns you want to pull into the primary table.

Clean Up

Post-merge, there might be redundant columns or mismatched data types.

Refine and clean your merged table as needed.

Back to Power BI

Once satisfied:

• Click 'Close & Apply'. Your Power BI model now reflects the merged data.

Performance Considerations

Merging large tables can impact performance.

Always monitor and optimize your queries for best results.

Conclusion:

Merging columns from different tables using Power Query is an essential skill in data shaping.

This process streamlines your data, helping you craft more comprehensive and insightful reports.

With practice, this tool can be wielded seamlessly, supercharging your Power BI journey!