列表函数 list-functions

differenceLists(listString,listString)：列表字符串

differenceLists(listInteger,listInteger)： listInteger

differenceLists(listDecimal,listDecimal)： listDecimal

differenceLists(listBoolean,listBoolean)：列表布尔值

differenceLists(listDuration,listDuration)： listDuration

differenceLists(listDateTime,listDateTime)： listDateTime

differenceLists(listDateTimeOnly,listDateTimeOnly)： listDateTimeOnly

differenceLists(listDateOnly,listDateOnly)： listDateOnly

differenceLists(['a','b','c'], ['b'])

返回['a','c']。

differenceLists(['a','a','b'], [])

返回['a','b']。

differenceLists([], ['a'])

返回[]。

distinct(<listInteger>)

返回整数列表。

distinct(<listDecimal>)

返回小数位数列表。

distinct(<listString>)

返回字符串列表。

distinct(<listDateTimeOnly>)

返回不考虑时区的日期时间列表。

distinct(<listDateTime>)

返回日期时间列表。

distinct(<listDateOnly>)

返回日期列表。

distinct(<listBoolean>)

返回布尔值列表。

distinct(<listDuration>)

返回持续时间列表。

distinct(<listObject>)

distinct(<listObject>,<string>)

返回对象列表。

distinct([10,2,10,null])

返回[10, 2]。

distinctWithNull(<listInteger>)

返回整数列表。

distinctWithNull(<listDecimal>)

返回小数位数列表。

distinctWithNull(<listString>)

返回字符串列表。

distinctWithNull(<listDateTimeOnly>)

返回不考虑时区的日期时间列表。

distinctWithNull(<listDateTime>)

返回日期时间列表。

distinctWithNull(<listDateOnly>)

返回日期列表。

distinctWithNull(<listBoolean>)

返回布尔值列表。

distinctWithNull(<listDuration>)

返回持续时间列表。

distinctWithNull([10,2,10,null])

返回[10， 2， null]

filter(listObject, string, listString)

filter(listObject, string, listInteger)

filter(listObject, string, listDecimal)

filter(listObject, string, listDateTime)

filter(listObject, string, listDateTimeOnly)

filter(listObject, string, listDateOnly)

filter(listObject, string, listDuration)

filter(listObject, string, listBoolean)

返回listObject。

以下是在传入事件“myevent”中传递的有效负载示例：

"productListItems": [{
   "id": "product1",
   "name": "the product 1",
   "price": 20
},{
   "id": "product2",
   "name": "the product 2",
   "price": 30
},{
   "id": "product3",
   "name": "the product 3",
   "price": 50
}]

您可以使用以下表达式：

filter(
 @event{myevent.productListItems},
 "id",
 ["product2", "product3", "product4"]
)

返回包含两个对象的listObject，其中“product2”和“product3”作为ID。

getListItem(<listInteger>,<index>)

返回整数。

getListItem(<listDecimal>,<index>)

返回小数。

getListItem(<listString>,<index>)

返回字符串。

getListItem(<listDateTimeOnly>,<index>)

返回不考虑时区的日期时间。

getListItem(<listDateTime>,<index>)

返回日期时间。

getListItem(<listDateOnly>,<index>)

返回日期列表。

getListItem(<listBoolean>,<index>)

返回布尔值。

getListItem(<listDuration>,<index>)

返回持续时间。

getListItem([10, 2, 3], 1)

返回“2”

getListItem(["A", "B", "C"], 2)

返回“C”

具有事件字段"event.appVersion"且值为"20.45.2.3434"的示例

split(@event{event.appVersion}, "\\.")

返回["20", "45", "2", "3434"]

getListItem(split(@event{event.appVersion}, "\\."), 0)

返回“20”

in(<integer>,<listInteger>)

in(<decimal>,<listDecimal>)

in(<string>,<listString>)

in(<boolean>,<listBoolean>)

in(<dateTimeOnly>,<listDateTimeOnly>)

in(<dateTime>,<listDateTime>)

in(<dateOnly>,<listDateOnly>)

in(<duration>,<listDuration>)

返回布尔值。

in(4,[4,5,3,4])

返回真。

in(8,[4,5,3,4])

返回假。

in(#{ExperiencePlatform.ProfileFieldGroup.profile.person.gender}, ["male"])

intersect(listString,listString)：列表字符串

intersect(listDecimal,listDecimal)： listDecimal

intersect(listInteger,listInteger)： listInteger

intersect(listDateTime,listDateTime)： listDateTime

intersect(listDateTimeOnly,listDateTimeOnly)： listDateTimeOnly

intersect(listDateOnly,listDateOnly)： listDateOnly

intersect(listDuration,listDuration)： listDuration

intersect(listBoolean,listBoolean)：列表布尔值

返回列表。

intersect(
    ["sports", "news", "documentary"],
    ["sports", "movies", "documentary"]
)

返回[“sports”，“news”]

intersect(
    #{ExperienceDataPlatform.profile.interests},
    ["sports", "documentary"]
)

返回配置文件属性和给定类别列表之间的通用项目。

intersect(
    #{ExperienceDataPlatform.profile.interests},
        @event{myEvent.sport_interests}
)

返回用户档案属性和给定事件字段之间的公用项。

limit(<listString>,<integer>)

limit(<listString>,<integer>,<boolean>)

返回字符串列表。

limit(<listInteger>,<integer>)

limit(<listInteger>,<integer>,<boolean>)

返回整数列表。

limit(<listDecimal>,<integer>)

limit(<listDecimal>,<integer>,<boolean>)

返回小数位数列表。

limit(<listBoolean>,<integer>)

limit(<listBoolean>,<integer>,<boolean>)

返回布尔值列表。

limit(<listDateOnly>,<integer>)

limit(<listDateOnly>,<integer>,<boolean>)

返回日期列表。

limit(<listDateTimeOnly>,<integer>)

limit(<listDateTimeOnly>,<integer>,<boolean>)

返回不考虑时区的日期时间列表。

limit(<listDateTime>,integer>)

limit(<listDateTime>,<integer>,<boolean>)

返回日期时间列表。

limit(<listDuration>,<integer>)

limit(<listDuration>,<integer>,<boolean>)

返回持续时间列表。

limit(<listObject>,<integer>)

limit(<listObject>,<integer>,<boolean>)

返回对象列表。

limit(["A", "B", "C", "D", "E"], 3)

返回["A","B","C"]。

limit(["A", "B", "C", "D", "E"], 3, false)

返回["C","D","E"]。

listSize(<listInteger>)

listSize(<listDecimal>)

listSize(<listString>)

listSize(<listBoolean>)

listSize(<listDateTimeOnly>)

listSize(<listDateTime>)

listSize(<listDateOnly>)

listSize(<listDuration>)

返回整数。

listSize(<listObject>)

listSize([10,2,3])

返回3。

listSize(@event{my_event.productListItems})

返回给定对象数组（listObject类型）中的对象数。

mergeLists(listString,listString,boolean)：列表字符串

mergeLists(listInteger,listInteger,boolean)： listInteger

mergeLists(listDecimal,listDecimal,boolean)： listDecimal

mergeLists(listBoolean,listBoolean,boolean)：列表布尔值

mergeLists(listDuration,listDuration,boolean)： listDuration

mergeLists(listDateTime,listDateTime,boolean)： listDateTime

mergeLists(listDateTimeOnly,listDateTimeOnly,boolean)： listDateTimeOnly

mergeLists(listDateOnly,listDateOnly,boolean)： listDateOnly

mergeLists(['a','b'], ['b','c'], true)

返回['a','b','c']。

mergeLists(['a','b'], ['b','c'], false)

返回['a','b','b','c']。

serializeList(<listInteger>,<string>,<boolean>)

serializeList(<listDecimal>,<string>,<boolean>)

serializeList(<listString>,<string>,<boolean>)

serializeList(<listBoolean>,<string>,<boolean>)

serializeList(<listDateTimeOnly>,<string>,<boolean>)

serializeList(<listDateTime>,<string>,<boolean>)

serializeList(<listDateOnly>,<string>,<boolean>)

serializeList(<listDuration>,<string>,<boolean>)

返回字符串。

serializeList(["Hello","World"], " ", false)

返回“Hello World”。

serializeList(["Hello", "World"], ",", true)

返回“Hello”、“World”。

sort(<listInteger>,<boolean>)

返回整数列表。

sort(<listDecimal>,<boolean>)

返回小数位数列表。

sort(<listString>,<boolean>)

返回字符串列表。

sort(<listDateTimeOnly>,<boolean>)

返回不考虑时区的日期时间列表。

sort(<listDateTime>,<boolean>)

返回日期时间列表。

sort(<listDateOnly>,<boolean>)

返回日期列表。

sort(<listBoolean>,<boolean>)

返回布尔值列表。

sort(<listObject>,<string>,<boolean>)

返回对象列表。

sort(["A", "C", "B"], true)

返回["A","B","C"]。

sort([1, 3, 2], false)

返回[3, 2, 1]。

sort(@event{my_event.productListItems}, "SKU", true)

返回按SKU属性排序的listObject（升序）

This section contains structured knowledge intended to support interpretation, retrieval, and question answering related to this topic.

For complete understanding, this information should be combined with the documentation on this page. Neither source is intended to stand alone; the page describes the feature, while this section provides additional context that helps disambiguate terminology, intent, applicability, and constraints.

• TL;DR: This page documents all list functions available in AJO journey expressions, covering how to filter, sort, deduplicate, check membership, limit, serialize, merge, subtract, and find intersections of lists and arrays.

Intents:

• Remove duplicate values from a list using distinct (ignoring nulls) or distinctWithNull (preserving nulls)
• Filter a listObject to return only objects matching specific key values using filter
• Retrieve an element at a specific index from a list using getListItem
• Check whether a value exists in a list using in
• Find common elements between two lists using intersect
• Combine two lists, with or without deduplication, using mergeLists
• Subtract one list from another (set difference) using differenceLists
• Return the first or last N elements of a list using limit
• Count the total number of elements in a list using listSize
• Convert a list to a delimited string using serializeList
• Sort a list in ascending or descending order using sort

Glossary:

• listObject: A list of complex objects that must be a field reference; cannot contain null objects (product-specific)
• keyAttributeName: An optional string parameter used with distinct, filter, and sort to identify which object attribute to use for deduplication, filtering, or sorting (product-specific)
• intersect: A set operation returning only the elements present in both input lists
• mergeLists: A set operation returning the union (deduplicated) or concatenation (with duplicates) of two lists, depending on the deduplicate parameter (product-specific)
• differenceLists: A set operation returning the items of the first list that are not present in the second list (product-specific)

Guardrails:

• distinctWithNull does not support the <listObject> parameter type
• filter requires the listObject parameter to be a field reference, not an inline literal
• listSize on a listObject requires the list to be a field reference; a listObject cannot contain null objects
• serializeList does not support the listObject type
• mergeLists and differenceLists only support scalar list types (string, integer, decimal, boolean, dateTime, dateTimeOnly, dateOnly, duration); listObject is not supported
• mergeLists’s deduplicate parameter must be a literal true/false, not a dynamic boolean expression
• differenceLists always deduplicates its result; there is no option to keep duplicates

Terminology:

• Canonical name: List functions — Acronym: none — variants: collection functions, array functions
• Synonyms: “listSize” = “count list elements”; “serializeList” = “join list to string”
• Do not confuse: “distinct” (ignores nulls) ≠ “distinctWithNull” (preserves null as a distinct value)
• Do not confuse: “limit” with third parameter true (returns first N items) ≠ “limit” with false (returns last N items)
• Do not confuse: “intersect” (common elements between two lists) ≠ “filter” (elements matching specific key values)
• Do not confuse: “mergeLists” (combines two lists, union or concatenation) ≠ “differenceLists” (subtracts one list from another) ≠ “intersect” (common elements only)

FAQ:

• Q: How do I get the first 3 items of a list? — Use limit(myList, 3) or limit(myList, 3, true); the default is to return the first items.
• Q: How do I get the last 3 items of a list? — Use limit(myList, 3, false).
• Q: What is the difference between distinct and distinctWithNull? — distinct ignores null values and excludes them from the result; distinctWithNull treats null as a distinct value and includes one null entry if any nulls are present.
• Q: Can I filter a list of strings with filter? — No, filter only works on listObject; for scalar lists use in or distinct for deduplication.
• Q: How do I check if a value is in a list? — Use in(value, myList), which returns true if the value is found in the list.
• Q: Can I sort a listObject by a specific attribute? — Yes, use sort(@event{...}, "attributeName", true) where the second parameter is the attribute name and the third is the sort direction (true = ascending).
• Q: How do I combine two lists and remove duplicates? — Use mergeLists(list1, list2, true).
• Q: How do I combine two lists but keep duplicate values? — Use mergeLists(list1, list2, false).
• Q: How do I find the items in one list that are not in another? — Use differenceLists(list1, list2), which returns the items of list1 not present in list2.
• Q: What is the difference between intersect and differenceLists? — intersect returns items common to both lists; differenceLists returns items in the first list that are absent from the second list.