Comparison Operators

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Comparison operators enable you to compare values in the left-hand side of an expression to the values in the right-hand side of an expression.

(left-hand side) (operator) (right-hand side)

These evaluations result in a Boolean true or false result and can be used as the basis for determining whether the action of transform is executed on the row or column of data. The following operators are supported:

Operator Name	Symbol	Example Expression	Output	Notes
less than	`<`	`3 < 6`	`true`
less than or equal to	`<=`	`6 <= 5`	false	The following operator generates an error: `=<`
greater than	>	`3 > 6`	`false`
greater than or equal to	>=	`6 >= 5`	`true`	The following operator generates an error: `=>`
equal to	==	`4 == 4`	`true`	For this comparison operator, you must use two equals signs, or an error is generated.
not equal to	`<>` or !=	4 <> 4	`false`	Both operators are supported. The following operator generates an error: `=!`

The above examples apply to integer values only. Below, you can review how the comparison operators apply to different data types.

Usage

Comparison operators are used to determine the condition of a set of data. Typically, they are applied in evaluations of values or rows.

For example, your dataset is the following:

city
San Francisco
Los Angeles
Chicago
New York

You could use the following transform to flag all rows whose city value equals San Francisco:

derive type:single value:(city == 'San Francisco')

Your output looks like the following:

city	column1
San Francisco	true
Los Angeles	false
Chicago	false
New York	false

You can optionally combine the above with an IF function, which enables you to write values for true or false outcomes:

derive type:single value:IF(city == 'San Francisco', 'Home of the Giants!', 'Some other team') as:'BaseballTeam'

Note that the optional as: clause can be used to rename the generated columns. See Derive Transform.

city	BaseballTeam
San Francisco	Home of the Giants!
Los Angeles	Some other team
Chicago	Some other team
New York	Some other team

Examples

Tip: For additional examples, see Common Tasks.

NOTE: When a comparison is applied to a set of values, the type of data of each source value is re-inferred to match any literal values used on the other side of the expression. This method allows for more powerful comparisons.

In the following examples, values taken from the MySource column are re-typed to match the inferred data type of the other side of the comparison.

Less Than (or Equal To)

Column Type	Example Transform	Output	Notes
Integer	`derive type:single value:(MySource < 5)`	`true` for all values in `MySource` that are less than 5. Otherwise, `false`.
Decimal	`keep row:(MySource <= 2.5)`	Retains all rows in the dataset where the value in the `MySource` column is less than or equal to 2.5.
Datetime	`keep row:(Date <= DATE(2009,12,31))`	Retains all rows whose `Date` column value is less than or equal to `12/31/2009`.	You can also use the `DATEDIF` function to generate the number of days difference between two date values. Then, you can compare this difference to another value. See DATEDIF Function.
String (and all other data types)	`derive type:single value:(LEN(MySource) < 5))`	`true` for any string value in the `MySource` column whose length is less than 5 characters. Otherwise, `false` See LEN Function.	For comparison purposes, all data types not previously listed in this table behave like strings. Since strings are non-numeric value, a function must be applied to string data to render a comparison.

Greater Than (or Equal To)

See previous section.

Equal to

Column Type	Example Transform	Output	Notes
Integer	`derive type:single value:(MySource == 5)`	`true` for all values in the `MySource` column that are 5. Otherwise, `false`.	If the source column contains Decimal values and the right-hand side is an integer value, the Decimal values that are also integers can match in the comparison (e.g. `2.0 == 2`).
Decimal	`keep row:(MySource == 2.5)`	Retains all rows in the dataset where the value in the `MySource` column is exactly 2.5.	If the source column contains integers and the right-hand side is a Decimal type value, integer values are rounded for comparison.
Datetime	`keep row:(Date == DATE(2016,12,25))`	Retains all rows whose `Date` column value is equal to `12/25/2016`.
String (and all other data types)	`keep row:(LEN(MySource) == 5))`	Retains all rows in the dataset where the length of the string value in the `MySource` column is 5 characters.	For comparison purposes, all data types not previously listed in this table behave like strings. Since strings are non-numeric value, a function must be applied to string data to render a comparison.

Not Equal to

Column Type	Example Transform	Output	Notes
Integer	`derive type:single value:(MySource <> 5)`	`true` for all values in the `MySource` column that are not 5. Otherwise, `false`.	If the source column contains Decimal values and the right-hand side is an integer value, the Decimal values that are also integers can match in the comparison (e.g. `2.0 == 2`).
Decimal	`keep row:(MySource <> 2.5)`	Retains all rows in the dataset where the value in the `MySource` column is not 2.5.	If the source column contains integers and the right-hand side is a Decimal type value, integer values are rounded for comparison.
Datetime	`keep row:(Date <> DATE(2016,4,15))`	Retains all rows in the dataset where the `Date` value does not equal 4/15/2016.
String (and all other data types)	`keep row:(LEN(MySource) <> 5))`	Retains all rows in the dataset where the length of the string value in the `MySource` column is not 5 characters.	For comparison purposes, all data types not previously listed in this table behave like strings. Since strings are non-numeric value, a function must be applied to string data to render a comparison.

See Also for Comparison Operators:

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