Conditional Functions

  • Capella Columnar
  • reference
    +
    This topic describes the builtin SQL++ for Capella columnar conditional functions.

    if_null (ifnull)

    • Syntax:

      if_null(expression1, expression2, ... expressionN)
    • Finds first argument which value is not null and returns that value

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • a null if all arguments evaluate to null or no arguments specified

      • a value of the first non-null argument otherwise

    • Example:

      {
          "a": if_null(),
          "b": if_null(null),
          "c": if_null(null, "analytics"),
          "d": is_missing(if_null(missing))
      };
    • The expected result is:

      { "a": null, "b": null, "c": "analytics", "d": true }

    The function has an alias ifnull.

    if_missing (ifmissing)

    • Syntax:

      if_missing(expression1, expression2, ... expressionN)
    • Finds first argument which value is not missing and returns that value

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • a null if all arguments evaluate to missing or no arguments specified

      • a value of the first non-missing argument otherwise

    • Example:

      {
          "a": if_missing(),
          "b": if_missing(missing),
          "c": if_missing(missing, "analytics"),
          "d": if_missing(null, "analytics")
      };
    • The expected result is:

      { "a": null, "b": null, "c": "analytics", "d": null }

    The function has an alias ifmissing.

    if_missing_or_null (ifmissingornull, coalesce)

    • Syntax:

      if_missing_or_null(expression1, expression2, ... expressionN)
    • Finds first argument which value is not null or missing and returns that value

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • a null if all arguments evaluate to either null or missing, or no arguments specified

      • a value of the first non-null, non-missing argument otherwise

    • Example:

      {
          "a": if_missing_or_null(),
          "b": if_missing_or_null(null, missing),
          "c": if_missing_or_null(null, missing, "analytics")
      };
    • The expected result is:

      { "a": null, "b": null, "c": "analytics" }

    The function has two aliases: ifmissingornull and coalesce.

    if_inf (ifinf)

    • Syntax:

      if_inf(expression1, expression2, ... expressionN)
    • Finds first argument which is a non-infinite (INF or-INF) number

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • a missing if missing argument was encountered before the first non-infinite number argument

      • a null if null argument or any other non-number argument was encountered before the first non-infinite number argument

      • the first non-infinite number argument otherwise

    • Example:

      {
          "a": is_null(if_inf(null)),
          "b": is_missing(if_inf(missing)),
          "c": is_null(if_inf(double("INF"))),
          "d": if_inf(1, null, missing) ],
          "e": is_null(if_inf(null, missing, 1)) ],
          "f": is_missing(if_inf(missing, null, 1)) ],
          "g": if_inf(float("INF"), 1) ],
          "h": to_string(if_inf(float("INF"), double("NaN"), 1)) ]
      };
    • The expected result is:

      { "a": true, "b": true, "c": true, "d": 1, "e": true, "f": true, "g": 1, "h": "NaN" }

    The function has an alias ifinf.

    if_nan (ifnan)

    • Syntax:

      if_nan(expression1, expression2, ... expressionN)
    • Finds first argument which is a non-NaN number

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • a missing if missing argument was encountered before the first non-NaN number argument

      • a null if null argument or any other non-number argument was encountered before the first non-NaN number argument

      • the first non-NaN number argument otherwise

    • Example:

      {
          "a": is_null(if_nan(null)),
          "b": is_missing(if_nan(missing)),
          "c": is_null(if_nan(double("NaN"))),
          "d": if_nan(1, null, missing) ],
          "e": is_null(if_nan(null, missing, 1)) ],
          "f": is_missing(if_nan(missing, null, 1)) ],
          "g": if_nan(float("NaN"), 1) ],
          "h": to_string(if_nan(float("NaN"), double("INF"), 1)) ]
      };
    • The expected result is:

      { "a": true, "b": true, "c": true, "d": 1, "e": true, "f": true, "g": 1, "h": "INF" }

    The function has an alias ifnan.

    if_nan_or_inf (ifnanorinf)

    • Syntax:

      if_nan_or_inf(expression1, expression2, ... expressionN)
    • Finds first argument which is a non-infinite (INF or-INF) and non-NaN number

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • a missing if missing argument was encountered before the first non-infinite and non-NaN number argument

      • a null if null argument or any other non-number argument was encountered before the first non-infinite and non-NaN number argument

      • the first non-infinite and non-NaN number argument otherwise

    • Example:

      {
          "a": is_null(if_nan_or_inf(null)),
          "b": is_missing(if_nan_or_inf(missing)),
          "c": is_null(if_nan_or_inf(double("NaN"), double("INF"))),
          "d": if_nan_or_inf(1, null, missing) ],
          "e": is_null(if_nan_or_inf(null, missing, 1)) ],
          "f": is_missing(if_nan_or_inf(missing, null, 1)) ],
          "g": if_nan_or_inf(float("NaN"), float("INF"), 1) ],
      };
    • The expected result is:

      { "a": true, "b": true, "c": true, "d": 1, "e": true, "f": true, "g": 1 }

    The function has an alias ifnanorinf.

    null_if (nullif)

    • Syntax:

      null_if(expression1, expression2)
    • Compares two arguments and returns null if they are equal, otherwise returns the first argument.

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • missing if any argument is a missing value,

      • null if

        • any argument is a null value but no argument is a missing value, or

        • argument1 = argument2

      • a value of the first argument otherwise

    • Example:

      {
          "a": null_if("analytics", "analytics"),
          "b": null_if(1, 2)
      };
    • The expected result is:

      { "a": null, "b": 1 }

    The function has an alias nullif.

    missing_if (missingif)

    • Syntax:

      missing_if(expression1, expression2)
    • Compares two arguments and returns missing if they are equal, otherwise returns the first argument.

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • missing if

        • any argument is a missing value, or

        • no argument is a null value and argument1 = argument2

      • null if any argument is a null value but no argument is a missing value

      • a value of the first argument otherwise

    • Example:

      {
          "a": missing_if("analytics", "analytics")
          "b": missing_if(1, 2),
      };
    • The expected result is:

      { "b": 1 }

    The function has an alias missingif.

    nan_if (nanif)

    • Syntax:

      nan_if(expression1, expression2)
    • Compares two arguments and returns NaN value if they are equal, otherwise returns the first argument.

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • missing if any argument is a missing value,

      • null if any argument is a null value but no argument is a missing value

      • NaN value of type double if argument1 = argument2

      • a value of the first argument otherwise

    • Example:

      {
          "a": to_string(nan_if("analytics", "analytics")),
          "b": nan_if(1, 2)
      };
    • The expected result is:

      { "a": "NaN", "b": 1 }

    The function has an alias nanif.

    posinf_if (posinfif)

    • Syntax:

      posinf_if(expression1, expression2)
    • Compares two arguments and returns +INF value if they are equal, otherwise returns the first argument.

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • missing if any argument is a missing value,

      • null if any argument is a null value but no argument is a missing value

      • +INF value of type double if argument1 = argument2

      • a value of the first argument otherwise

    • Example:

      {
          "a": to_string(posinf_if("analytics", "analytics")),
          "b": posinf_if(1, 2)
      };
    • The expected result is:

      { "a": "+INF", "b": 1 }

    The function has an alias posinfif.

    neginf_if (neginfif)

    • Syntax:

      neginf_if(expression1, expression2)
    • Compares two arguments and returns -INF value if they are equal, otherwise returns the first argument.

    • Arguments:

      • expressionI : an expression of any type.

    • Return Value:

      • missing if any argument is a missing value,

      • null if any argument is a null value but no argument is a missing value

      • -INF value of type double if argument1 = argument2

      • a value of the first argument otherwise

    • Example:

      {
          "a": to_string(neginf_if("analytics", "analytics")),
          "b": neginf_if(1, 2)
      };
    • The expected result is:

      { "a": "-INF", "b": 1 }

    The function has an alias neginfif.