🧠 Power BI DAX | Difference between FILTER, FILTERS, and KEEPFILTERS 🧩

 Understanding the difference between FILTER, FILTERS, and KEEPFILTERS in DAX is crucial for mastering context manipulation in Power BI.

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1️⃣ FILTER Function 🔍

Used to create a table expression that returns filtered rows from a table.

Syntax:

Dax

FILTER(table, condition)

✅ Best for complex row-level conditions.

📌 Example:

Dax

CALCULATE(SUM(Sales[Amount]), FILTER(Sales, Sales[Region] = "East"))

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2️⃣ FILTERS Function 🧾

Returns the current filter context applied on a column.

Syntax:

Dax

FILTERS(column)

✅ Used to check which filters are active.

📌 Example:

Dax

IF(ISFILTERED(Sales[Region]), VALUES(Sales[Region]), "All Regions")

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3️⃣ KEEPFILTERS Function 📌

Preserves the existing filters when used inside CALCULATE, instead of overriding them.

Syntax:

Dax

CALCULATE([Measure], KEEPFILTERS(table[column] = value))

✅ Ensures additive filter logic instead of replacement.

📌 Example:

Dax

CALCULATE(SUM(Sales[Amount]), KEEPFILTERS(Sales[Region] = "East"))

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⚖️ Quick Comparison Table

Function	Purpose	Context Use
FILTER	Returns filtered table	Row-level filtering
FILTERS	Returns filter context values	Context checks (e.g., slicers)
KEEPFILTERS	Keeps existing filters	Combine filters in CALCULATE