Append Data expressions

Expressions are used in the Append Data tool to calculate input layer fields using append layer field values. When you're not appending fields from the append layer, use expressions to specify how each feature will be populated. An Append Data expression should result in values of the same type as the field. Expression examples are included in the following sections.

The Append Data tool was introduced at 10.6.1 and can use Arcade expressions to append field values. Using Arcade, field names are formatted as $feature["field name"] or $feature.fieldname. The first option, $feature["field name"], is required when a field name includes a space. All examples below use this option.

Learn more about Arcade expressions

The following tools use Arcade expressions in GeoAnalytics Server:

Reconstruct Tracks—Buffer expressions.
Create Buffers—Buffer expressions.
Join Features—Join expressions.
Detect Incidents—Detect incidents using start and end expressions.
Calculate Field—Calculate field values.

Legacy:

The ArcGIS GeoAnalytics Server extension is being deprecated in ArcGIS Enterprise. The final release of GeoAnalytics Server was included with ArcGIS Enterprise 11.3. These tools are available through ArcGIS Enterprise 11.3 and earlier versions.

Mathematical operation and function examples

Expressions can mathematically process numbers. The following table shows examples of available operations.

Learn more about mathematical operations and functions in Arcade


Operator	Explanation	Example
`a + b`	Returns the sum of a plus b.	`fieldname` contains a value of 1.5 `$feature["fieldname"] + 2.5` 4.0
`a - b`	Returns the difference of a minus b.	`fieldname` contains a value of 3.3 `$feature["fieldname"]- 2.2` 1.1
`a * b`	Returns the product of a times b.	`fieldname` contains a value of 2.0 `$feature["fieldname"] * 2.2` 4.4
`a / b`	Returns the quotient of a divided by b.	`fieldname` contains a value of 4.0 `$feature["fieldname"] / 1.25` 3.2
`abs( a )`	Returns the absolute (positive) value of a.	`fieldname` contains a value of -1.5 `abs($feature["fieldname"])` 1.5
`log( a )`	Returns the natural logarithm (base E) of a.	`fieldname` contains a value of 1 `log($feature["fieldname"])` 0
`sin( a )`	Returns the trigonometric sine of a. The input is assumed to be an angle in radians.	`fieldname` contains a value of 1.5707 `sin($feature["fieldname"])` 1
`cos( a )`	Returns the trigonometric cosine of a. The input is assumed to be an angle in radians.	`fieldname` contains a value of 0 `cos($feature["fieldname"])` 1
`tan( a )`	Returns the tangent of a. The input is assumed to be an angle in radians.	`fieldname` contains a value of 0 `tan($feature["fieldname"])` 0
`sqrt( a )`	Returns the square root of a.	`fieldname` contains a value of 9 `sqrt($feature["fieldname"])` 3
`min( a, b )`	Returns the lowest valued number between a and b.	`fieldname` contains a value of 1.5, and a value of -3 `min($feature["fieldname"], -3)` -3
`max( a, b )`	Returns the highest valued number between a and b.	`fieldname1` contains a value of 1.5, and `fieldname2` contains a value of -3 `max($feature["fieldname1"], $feature["fieldname2"])` 1.5
`constrain(<value>,<low>,<high>)`	Returns the input value if it's within the constraining bounds. If the value is less than the low value, it returns the low value. If the value is greater than the high value, it returns the high value.	Example 1: `constrain( $feature["distance"], 0, 10)` Returns 0 if `distance` is less than 0, 10 if `distance` is greater than 10, and `distance` otherwise. Example 2: `constrain($feature['Store dist'], 6, distance)` Returns 6 if `Store dist` is less than 6, `distance` if `Store dist` is greater than `distance`, and `Store dist` otherwise.

Text function examples

Append Data expressions can process text. The following table shows examples of available operations.

Learn more about text functions in Arcade


Operator	Explanation	Example	Result
`concatenate(<values>, <separator>)`	Concatenates values together and returns a string. `values`—An array of string values to concatenate. `separator` ( optional)—A separator to use for concatenation if the `values` parameter is an array, or a string to concatenate if a single value is provided for the first parameter. If not provided, it will be empty.	`fieldname` contains a value of `GeoAnalytics` `Concatenate ([$features["fieldname"], "is", "great!"], ' ')`	GeoAnalytics is great!
`find(<searchText>, <text>, <startPos>)`	Finds a string within a string. Wildcards are not supported. `searchText`—The substring to search for. `text`—The text to search. `startPos` (optional)—The zero-based index of the location in the string to search from.	`fieldname1` contains a value of `14NorthStreet` and `fieldname2` contains a value of `North` `find($feature["fieldname2"], $feature["fieldname1"])`	2
`lower(<value>)`	Makes a string lowercase. `value`—The string to be made lowercase.	`fieldname` contains a value of `GEOANALYTICS` `lower($feature["fieldname"])`	geoanalytics

Text example using find and lower.

find(("north"), lower("146NorthStreet"))

Date function examples

Append Data expressions can process dates. The following table shows examples of available operations. In Arcade, month values range from 0 (January) to 11 (December), day values from the 1st to the 31st, hour values from 0 (12:00 a.m.) to 23 (11:00 p.m.), minute and second values from 0 to 59, and millisecond values from 0 to 999. Arcade dates return time values for the GeoAnalytics Server location.

Learn more about date functions in Arcade


Operator	Explanation	Example	Result
`date(<value>, <month>, <day>, <hour>, <minute>)`	Parses a value or set of values into a date string. `value` (optional)— Either the number of milliseconds since January 1, 1970, UTC or a number representing a year. If a year is specified, the month and day must also be provided in subsequent parameters. This value can also be a date string or an ISO 8601 string to be converted to a date. `month` (optional)—The month (0-11), where 0 is January and 11 is December. `day` (optional)—The day of the month (1-31). `hour` (optional)—The hour of the day (0-23). `minute` (optional)—The minute of the hour (0-59). `second` (optional)—The second of the minute (0-59). `millisecond` (optional)—The millisecond of the second (0-999).	`fieldname` contains a value of `1476987783555` Example 1: `Date($features["fieldname"])` Example 2: `Date(2017,0,14,0)` Example 3: `Date()`	Example 1: 20 Oct 2016 11:23:03 am Example 2: 14 Jan 2017 12:00:00 am Example 3: Returns the current time
`DateDiff(<date1>, <date2>, <units>)`	Subtracts two dates and returns the difference in the specified units. `date1`—The date value from which to subtract a second date. `date2`—The date value to subtract from the first given date. `units` (optional)—The units used to return the difference of the two given dates. The supported unit types are `milliseconds`, `seconds`, `minutes`, `hours`, `days`, `months`, and `years`. The default value is `milliseconds`.	Example 1: `DateDiff(Date(2017,1,14,0), Date())` Example 2: `DateDiff(Date(2017,1,14,0), Date(), "Years")`	Result will vary depending on when you run this command. Example 1: -20532129137 Example 2: -0.6546783768647119
`Year(<dateValue>)`	Returns the year of the given date. `value`—A date value identifying the year.	Example 1: `fieldname` is a field of type Date with a value of `09 Oct 2017 04:30:43 pm` `Year($feature["fieldname"])` Example 2: `fieldname` is a string field formatted as an ISO 8601 string with a value of `2012-09-27`	Example 1: 2017 Example 2: 2012

Logical function examples

In addition to simple mathematical expressions, more advanced functions, shown in the following table, can be used to apply buffer expressions.


Function	Explanation	Example	Result
`iif(<condition>,<true value>,<false value>)`	Returns one value if a condition evaluates to `true` and returns another value if that condition evaluates to `false`. `<true value>` and `<false value>` can be the following: A numeric field. If there is a space in the field name, use square brackets. A number. A function.	`iif($feature["field1"] > $feature["field2"], $feature["field1"], 0)` `iif($feature["field1"] > $feature["field2"], iif($feature["field2"] = 0, $feature["field3"], $feature["field4"]), 0)`	Returns `field1` if `field1` is greater than `field2`, and `0` otherwise. Returns the result of the second `iif` function if `field1` is greater than `field2`, and `0` otherwise.
`when(<expression1> , <result1> , <expression2> , <result2> , ... , <expressionN> , <resultN>, <default>)`	Evaluates a series of expressions in order until one evaluates to `true`. `expression`—An expression. `result`—The result of the expression. It can be a number or field. `default`—An optional value if none of the expressions match.	`when(($feature["field1"] + 10) > 1, 1,($feature["field2"] + 10) > 2 , 2, $feature["field3"])`	If `field1 + 10` is greater than 1, returns 1. If not, checks if `field2 + 10` is greater than 2. If yes, it returns 2. If not, it returns `field3`.
`decode(<conditional val> , <case1> , <result1>, <case2>, <result2>, ... <caseN>, <resultN>, <defaultValue> )`	Evaluates an expression and compares its value with subsequent parameters. If the expression matches, it returns the next parameter value. If none match, there is the option for the last parameter to be a default return value. `conditional val`—The conditional value. It can be a field or an expression. `case`—A value to be compared to the `conditional val`. `result`—The result if the corresponding case matches the `conditional val`. `defaultValue`—An optional value if no other values are `true`.	`decode($feature["field1"] + 3 , $feature["field1"], 1, $feature["field2"], 2, 0)`	Compares equality between the conditional val `field1 + 3` and case1 `field1`. If `true`, it returns 1. If `false`, it compares the equality between `field1 + 3` and `field2`. If `true`, it returns 2; otherwise, it returns 0.

Conditional operators

Conditional statements can use the following operators:


Operator	Explanation	Example	Results
`a > b` `a < b`	a is greater than b a is less than b	`10 > 2`	False
`a >= b` `a <= b`	a is greater than or equal to b a is less than or equal to b	`abs(-10) >= 10`	True
`a != b`	a is not equal to b	`abs(-3) != -3`	True
`a == b`	a is equal to b	`abs(-5) == 5`	True
`<condition1> \|\| <condition2>`	Condition 1 or condition 2 is met.	`(abs(-5) == 5) \|\| (10 < 2)`	True
`<condition1> && <condition2>`	Condition 1 and condition 2 are met.	`(abs(-5) == 5) && (10 < 2)`	False