How do I handle mixed timestamp formats in PowerBI?

If you try to convert a mixed column to "Date/Time" all at once, Power BI will return Errors for any format it doesn't recognize.

Here is the professional approach to normalizing mixed timestamps using Power Query:

1. The "Try and Catch" Strategy (Recommended)

This is the most robust method. You attempt to parse the date using one format, and if it fails, you try the second format.

How to do it (Custom Column):
In Power Query, go to Add Column > Custom Column and use this logic:

let 
    // Try Format 1 (ISO Standard)
    date1 = try DateTime.FromText([TimestampString], "en-US"),
    // Try Format 2 (Alternative)
    date2 = try DateTime.FromText([TimestampString], "en-GB")
in 
    if date1[HasError] = false then date1[Value] else date2[Value]

• Why this works: It allows the script to be flexible. If the Windows agent uses US formatting and the Linux agent uses ISO, this column will correctly interpret both.

2. Using "Using Locale" (The Easy Way)

If the issue is simply that one file is from a UK server (DD/MM) and another is from a US server (MM/DD), you can use the Locale setting.

• Action: Right-click the column > Change Type > Using Locale...
• Selection: Choose Date/Time and then select the Region that matches the majority of your logs. Power BI is much smarter at guessing formats when it knows the intended region.

3. Normalizing via "Replace Values"

Sometimes the "mixed" format is just a slight character difference (e.g., some logs use a comma , before milliseconds and others use a period .).

• Action: Before converting to Date/Time, use Transform > Replace Values.
• Example: Replace all , with . in your timestamp column.
• Result: This creates a uniform string that the standard "Change Type" tool can handle easily.

4. Handling "Unix Epoch" vs. "Human Readable"

Rarely, you might see some internal Spirion logs using Unix timestamps (long strings of numbers like 1715800000).

• The Fix: Use a conditional column.
• Logic: if Text.Length([TimestampString]) > 10 then [Convert Unix Logic] else [Standard Parse].
• (Note: Standard Spirion IDF/EPS logs almost always use Human Readable formats, but database-level logs may differ.)

Updated M Code for Mixed Formats

Add this step to your script to handle the two most common Spirion timestamp variations:

    // Add this after your "SplitHeader" step
    NormalizeTimestamp = Table.AddColumn(SplitHeader, "FinalTimestamp", each 
        let
            // Attempt 1: Standard ISO (2024-05-15)
            AttemptISO = try DateTime.FromText([TimestampString], [Format="yyyy-MM-dd HH:mm:ss", Culture="en-US"]),
            // Attempt 2: US Standard (5/15/2024)
            AttemptUS = try DateTime.FromText([TimestampString], [Format="M/d/yyyy h:mm:ss tt", Culture="en-US"])
        in
            if AttemptISO[HasError] = false then AttemptISO[Value] 
            else if AttemptUS[HasError] = false then AttemptUS[Value] 
            else null // Returns null if both fail for manual inspection
    ),
    
    // Change the type of the new column
    FinalType = Table.TransformColumnTypes(NormalizeTimestamp,{{"FinalTimestamp", type datetime}})

SME Summary Checklist for Mixed Timestamps:

1. Don't Force It: Never just click "Change Type" if you see multiple formats; you will lose data to errors.
2. Clean First: Use "Replace Values" to fix delimiters (commas, dots, slashes).
3. Use try Logic: Use the try...otherwise pattern in M code to cycle through known formats.
4. Check for Nulls: After running your logic, filter for null in your new timestamp column. If you find any, it means you've discovered a third format you need to add to your script.

Summary: Use the try DateTime.FromText logic in a Custom Column to attempt multiple parsing formats. This ensures that logs from different regions or agent versions are normalized into a single, sortable timeline without generating errors.