ARRAY_SLICE - Cosmos DB 中的查询语言(在 Azure 和 Fabric 中)

ARRAY_SLICE 函数使用指定的索引和长度返回数组表达式的子集。

Syntax

ARRAY_SLICE(<array_expr>, <numeric_expr_1> [, <numeric_expr_2>])

Arguments

Description
array_expr 数组表达式。
numeric_expr_1 一个数值表达式,指示要在其中开始子集数组的索引。 (可选)负值可用于指定相对于数组的最后一个元素的起始索引。
numeric_expr_2 一个可选的数值表达式,指示生成的数组中元素的最大长度。

返回类型

返回数组表达式。

例子

本部分包含有关如何使用此查询语言构造的示例。

数组切片示例

在此示例中,函数 ARRAY_SLICE 用于获取数组的子集。

SELECT VALUE {
  sliceFromStart: ARRAY_SLICE(["Alpha", "Bravo", "Charlie", "Delta", "Echo", "Foxtrot", "Golf"], 0),
  sliceFromSecond: ARRAY_SLICE(["Alpha", "Bravo", "Charlie", "Delta", "Echo", "Foxtrot", "Golf"], 1),
  sliceFromLast: ARRAY_SLICE(["Alpha", "Bravo", "Charlie", "Delta", "Echo", "Foxtrot", "Golf"], -1),
  sliceFromSecondToLast: ARRAY_SLICE(["Alpha", "Bravo", "Charlie", "Delta", "Echo", "Foxtrot", "Golf"], -2),
  sliceThreeFromStart: ARRAY_SLICE(["Alpha", "Bravo", "Charlie", "Delta", "Echo", "Foxtrot", "Golf"], 0, 3),
  sliceTwelveFromStart: ARRAY_SLICE(["Alpha", "Bravo", "Charlie", "Delta", "Echo", "Foxtrot", "Golf"], 0, 12),
  sliceFiveFromThird: ARRAY_SLICE(["Alpha", "Bravo", "Charlie", "Delta", "Echo", "Foxtrot", "Golf"], 3, 5),
  sliceOneFromSecondToLast: ARRAY_SLICE(["Alpha", "Bravo", "Charlie", "Delta", "Echo", "Foxtrot", "Golf"], -2, 1)
}
[
  {
    "sliceFromStart": [
      "Alpha",
      "Bravo",
      "Charlie",
      "Delta",
      "Echo",
      "Foxtrot",
      "Golf"
    ],
    "sliceFromSecond": [
      "Bravo",
      "Charlie",
      "Delta",
      "Echo",
      "Foxtrot",
      "Golf"
    ],
    "sliceFromLast": [
      "Golf"
    ],
    "sliceFromSecondToLast": [
      "Foxtrot",
      "Golf"
    ],
    "sliceThreeFromStart": [
      "Alpha",
      "Bravo",
      "Charlie"
    ],
    "sliceTwelveFromStart": [
      "Alpha",
      "Bravo",
      "Charlie",
      "Delta",
      "Echo",
      "Foxtrot",
      "Golf"
    ],
    "sliceFiveFromThird": [
      "Delta",
      "Echo",
      "Foxtrot",
      "Golf"
    ],
    "sliceOneFromSecondToLast": [
      "Foxtrot"
    ]
  }
]

注解

  • 此函数不使用索引。