Daily DAX : Day 465 ISDECIMAL

DAX ISDECIMAL Function

ISDECIMAL checks if a value has the decimal number data type in Power BI (also known as fixed-precision decimal / currency type).

Syntax

ISDECIMAL ( <value> )
ParameterDescription
<value>The expression or column value to test

Return Value

  • TRUE → value is a decimal number (fixed decimal / Currency type)
  • FALSE → value is anything else (whole number, float/double, text, date, blank, etc.)

Important Notes

  • ISDECIMAL is just another name (alias) for ISCURRENCY
  • In Power BI, "Decimal Number" usually means floating point (Double), while Fixed Decimal Number = Currency type = what ISDECIMAL detects
  • Not supported in DirectQuery mode (calculated columns or RLS rules)

Common Use Cases

1. Clean mixed imported data (most common real-world use)

ValidCurrency = 
IF(
    ISDECIMAL ( 'Sales'[Amount Imported] ),
    'Sales'[Amount Imported],
    BLANK()
)

→ Only keeps values that are real decimal/currency type

2. Different formatting or calculation based on data type

Formatted Amount = 
SWITCH(
    TRUE(),
    ISDECIMAL ( [Value] ), FORMAT ( [Value], "$#,##0.00" ),
    ISNUMBER  ( [Value] ), FORMAT ( [Value], "#,##0" ),
    "–"
)

3. Detect legacy imported "money" columns

IsLegacyCurrencyColumn = 
ISDECIMAL ( SELECTEDVALUE ( 'Fact'[Legacy Amount] ) )

→ Helps identify columns that came in as fixed-decimal instead of float

Quick Comparison Table

Function Returns TRUE for Typical Use
ISNUMBERAny number (Integer + Decimal + Float)General number check
ISDECIMAL / ISCURRENCYOnly fixed decimal (Currency type)Detect money/precision columns
ISINT64Whole numbers (64-bit integer)Check pure integers


Comments

Post a Comment

Popular posts from this blog

Daily DAX : Day 131 SELECTEDMEASURE

 The SELECTEDMEASURE function in Power BI's DAX (Data Analysis Expressions) language is a powerful tool used primarily within calculation groups to dynamically reference the measure currently being evaluated in a report. It’s part of the calculation group feature introduced to streamline complex reporting scenarios and improve maintainability by reducing the need to duplicate measure logic. What is SELECTEDMEASURE? SELECTEDMEASURE is a DAX function that returns a reference to the measure that is currently active or "selected" in the context of a calculation group. It doesn’t take any arguments and is typically used in the expression of a calculation item within a calculation group. This allows you to write generic logic that can dynamically apply to whichever measure is being evaluated in a visual, without hardcoding specific measure names. Syntax SELECTEDMEASURE()     Returns: A reference to the measure currently being evaluated in the report context. Use Case SELECTEDME...
Read more

Daily DAX : Day 191 MROUND

MROUND DAX Function Syntax: dax MROUND(<number>, <multiple>)     number: The value you want to round.     multiple: The multiple to which you want to round the number. Description: The MROUND function rounds the number to the nearest value that is a multiple of the specified multiple. If the number is exactly halfway between two multiples, it rounds away from zero (e.g., 2.5 to 3 for a multiple of 1). Return Value: A number rounded to the nearest multiple of the specified value. Examples     Basic Rounding:     dax     MROUND(23, 5)         Returns 25, as 25 is the nearest multiple of 5 to 23.     Rounding to Nearest 10:     dax     MROUND(17, 10)         Returns 20, as 20 is the nearest multiple of 10 to 17.     Negative Numbers:     dax     MROUND(-23, 5)         Returns -25, as -25 is the nearest multiple...
Read more

Daily DAX : Day 142 COLLAPSEALL

 The COLLAPSEALL function in Power BI's Data Analysis Expressions (DAX) language is a visual calculation function designed to navigate and manipulate the context of hierarchical data within a visual, such as a matrix or table. Introduced as part of the visual calculations feature in Power BI, it allows users to "collapse" the visual context to the highest level of a specified hierarchy or axis, effectively removing all lower-level details. This function is particularly useful when working with hierarchical data structures (e.g., year > quarter > month) and performing calculations that need to reference aggregated values at the topmost level. Syntax There are two primary forms of the COLLAPSEALL function:     With an Expression (Returns a Value):     COLLAPSEALL(<expression>, <axis>)         <expression>: The calculation or measure you want to evaluate (e.g., [SalesAmount]).         <axis>: The...
Read more