# Data Mapping functions


The [**Data Mapping** task](https://docs.cloud.google.com/application-integration/docs/configure-data-mapping-task) provides various predefined mapping functions to transform and standardize the mapping data in your integration. A mapping function can have one or more input parameters, wherein each parameter can further hold a literal value, a variable, or a base function with mapping functions applied. You can use multiple mapping functions for a single input source, forming a mapping [transform expression](https://docs.cloud.google.com/application-integration/docs/data-mapping-overview#transform).


The following table lists the predefined mapping functions available in the **Data Mapping** task.

| Function | Description |
|---|---|
| [`ADD`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/add-function-reference) | Adds the specified number to an existing number. |
| [`AND`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/and-function-reference) | Performs the logical AND operation on the specified boolean values. |
| [`APPEND`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/append-function-reference) | Appends the specified value to an array. |
| [`APPEND_ALL`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/append-all-function-reference) | Appends all the specified values to an array. |
| [`APPEND_ELEMENT`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/append-element-function-reference) | Appends an element to a JSON array. |
| [`AVG`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/avg-function-reference) | Calculates the numerical average of all the values in an array. |
| [`CEIL`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/ceil-function-reference) | Computes the smallest integer that is greater than or equal to the given input. |
| [`CONCAT`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/concat-function-reference) | Concatenates the specified characters to an existing string. |
| [`CONTAINS`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/contains-function-reference) | Checks the occurrence of the specified value in a given string or string array. |
| [`DECODE_BASE64_STRING`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/decode-base64-string-function-reference) | Decodes a base64 string to UTF-8 charset. |
| [`DIVIDE`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/divide-function-reference) | Divides an existing number by the specified number. |
| [`EQUALS`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/equals-function-reference) | Compares the specified value with the existing value. |
| [`EQUALS_IGNORE_CASE`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/equals-ignore-case-function-reference) | Compares the specified value with the existing value. |
| [`EPOCH_TO_HUMAN_READABLE_TIME`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/epoch-to-human-readable-time-function-reference) | Converts Unix epoch time (in milliseconds) to human-readable time format. |
| [`EXPONENT`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/exponent-function-reference) | Calculates the value of an existing number raised to the specified power. |
| [`FILTER`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/filter-function-reference) | Filters the array elements that satisfy a given filter condition. Note that a filter condition must evaluate to TRUE or FALSE. |
| [`FLATTEN`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/flatten-function-reference) | Flattens a JSON array recursively to create a new one-dimensional array. |
| [`FLOOR`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/floor-function-reference) | Computes the greatest integer that is less than or equal to the provided input. |
| [`FOR_EACH`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/for-each-function-reference) | Applies one or more transformation functions for each element in an array. |
| [`GET`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/get-function-reference) | Returns the value in an array at a specified index. In an array, the first value is available at index 0 and the last value is available at index n-1 where n is the size of the array. |
| [`GET_ELEMENT`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/get-element-function-reference) | Returns the element at the specified index in a JSON array. In the array, the first value is available at index 0 and the last value is available at index n-1 where n is the size of the array. |
| [`GET_PROPERTY`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/get-property-function-reference) | Returns the value of the specified property in a JSON object. |
| [`GREATER_THAN`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/greater-than-function-reference) | Checks if an existing number is greater than the specified number. |
| [`GREATER_THAN_EQUAL_TO`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/greater-than-equal-to) | Checks if an integer is greater than or equal to the specified value. |
| [`LENGTH`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/length-function-reference) | Calculates the length of a string. The length of a string is the number of characters in the string. |
| [`LESS_THAN_EQUAL_TO`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/less-than-equal-to-function-reference) | Checks if an integer is less than or equal to the specified value. |
| [`LESS_THAN`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/less-than-function-reference) | Checks if an existing number is less than the specified number. |
| [`MAX`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/max-function-reference) | Finds the highest value in an array. |
| [`MERGE`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/merge-function-reference) | Merges two JSON variables (objects or arrays). If same value is present in both the variables, the function removes the duplicate value. |
| [`MIN`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/min-function-reference) | Finds the lowest value in an array. |
| [`MOD`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/mod-function-reference) | Divides two values and returns the remainder of the division operation. |
| [`MULTIPLY`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/multiply-function-reference) | Multiplies an existing number by the specified number. |
| [`NAND`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/nand-function-reference) | Performs the logical NAND operation on the specified boolean values. |
| [`NOR`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/nor-function-reference) | Performs the logical NOR operation on the specified boolean values. |
| [`NOT`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/not-function-reference) | Returns the opposite value of a boolean. |
| [`OR`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/or-function-reference) | Performs the logical OR operation on the specified boolean values. |
| [`REMOVE`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/remove-function-reference) | Removes the specified value from an array. |
| [`REMOVE_AT`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/remove-at-function-reference) | Removes an element from an array at the specified index. |
| [`REMOVE_PROPERTY`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/remove-property-function-reference) | Removes a property from a JSON object. |
| [`REPLACE_ALL`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/replace-all-function-reference) | Replaces all the occurrences of a substring in a string. |
| [`RESOLVE_TEMPLATE`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/resolve-template-function-reference) | Resolves references in a template string that contains $variable$ references. |
| [`ROUND`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/round-function-reference) | Rounds a number to the nearest integer. |
| [`SET`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/set-function-reference) | Updates the value of a string array at the specified index. |
| [`SET_PROPERTY`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/set-property-function-reference) | Adds or updates a property in a JSON object. |
| [`SIZE`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/size-function-reference) | Counts the number of elements in an array. |
| [`SPLIT`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/split-function-reference) | Splits a string based on the specified delimiter. |
| [`SUBSTRING`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/substring-function-reference) | Returns the substring of the current string from the start index inclusive to the end index exclusive. |
| [`SUBTRACT`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/subtract-function-reference) | Subtracts the specified number from an existing number. |
| [`SUM`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/sum-function-reference) | Adds all the values in an array. |
| [`TO_BASE_64`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-base-64-function-reference) | Encodes a string to base64 format using the UTF-8 charset. |
| [`TO_BOOLEAN_ARRAY`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-boolean-array-function-reference) | Converts a JSON array to a boolean array. |
| [`TO_BOOLEAN`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-boolean-function-reference) | Converts a string to a boolean data type. |
| [`TO_DOUBLE_ARRAY`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-double-array-function-reference) | Converts a JSON array to a double array. |
| [`TO_DOUBLE`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-double-function-reference) | Converts a string or an integer to a double. |
| [`TO_INT_ARRAY`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-int-array-function-reference) | Converts a JSON array to an integer array. |
| [`TO_INT`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-int-function-reference) | Converts a string to an integer. |
| [`TO_JSON`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-json-function-reference) | Converts the current value to a JSON object. |
| [`TO_LOWERCASE`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-lowercase-function-reference) | Converts all the characters in a string to lowercase. |
| [`TO_SET`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-set-function-reference) | Removes duplicate values in an array. |
| [`TO_STRING_ARRAY`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-string-array-function-reference) | Converts a JSON array to a string array. |
| [`TO_UPPERCASE`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/to-uppercase-function-reference) | Converts all the characters in a string to uppercase. |
| [`XNOR`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/xnor-function-reference) | Performs the logical XNOR operation on the specified boolean values. |
| [`XOR`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/xor-function-reference) | Performs the logical XOR operation on the specified boolean values. |
| [`GENERATE_UUID`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/generate-uuid-function-reference) | Generates a random UUID. |
| [`GET_EXECUTION_ID`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/get-execution-id-function-reference) | Returns the execution ID of the current integration. |
| [`GET_INTEGRATION_NAME`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/get-integration-name-function-reference) | Returns the name of the current integration. |
| [`GET_INTEGRATION_REGION`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/get-integration-region-function-reference) | Returns the region of the current integration. |
| [`GET_PROJECT_ID`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/get-project-id-function-reference) | Returns the Google Cloud project ID of the current integration. |
| [`INT_LIST`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/int-list-function-reference) | Returns an integer list between the specified values. The returned list is inclusive of the starting value and exclusive of the ending value. |
| [`NOW_IN_MILLIS`](https://docs.cloud.google.com/application-integration/docs/reference/data-mapping-reference/now-in-millis-function-reference) | Returns the current Unix epoch time of the integration in milliseconds. |