Best Practices When Writing Formulas

The formula syntax affects the way the formula is queried.

When writing a formula, use these syntax rules.

  • Use the correct functions as described in Adding Functions.
  • Surround fields in the formula by brackets.
  • Use the correct operator syntax
  • Use the correct literal expression syntax
    • Numeric literal expressions are written as numbers. For example, 1.3567.
    • String literal expressions are written with quotation marks. For example, “Unprofitable”.
    • Date literal expressions are written with the # symbol. For example: #August 22, 2024#.
    • Null literal expressions are written as “null”.
    • Tableau Semantics uses Tableau literal expressions. Learn more about literal expressions in the Tableau Literal expression syntax documentation.
  • Use the correct date function syntax:
    • Date functions are hardcoded in ISO format:
      • Date: "yyyy—MM—dd" or "yyyymmdd" or "yyyy—MM" OR “yyyy”
      • Time:
        • Hh:mm:ss
        • Hh:mm:ss.sss
        • HH:mm:ss.SSSSSS
        • Hh:mm:ssZZZZ
        • Hh:mm:ssSS.ZZZZZ
        • "T[hh][mm][ss]"
        • "T[hh]:[mm]:[ss] "
        • “T[hh]:[mm]:[ss]ZZZZZ”
      • Datetime: "<date>T<time>" or "<date> <time>" or "<date>’T’<time>"
      • Examples:

        "2020—02—08T09"

        "2020—02—08 09"

        "2020—02—08 09:30:26"

        "2020—02—08 09:30:26.123"

    • Use DATEPARSE for other formats.
  • Use the correct comment syntax
    • To enter a comment in a calculation, type two forward slashes: //
    • Multiline comments can be added by typing /* to start the comment and */ to end the comment.
    • Example of a formula with comments:
      SUM([Sales]) / SUM([Profit])
      
      /*John's calculation
      
      To be used for profit ratio
      
      Do not edit*/