某些数据源（例如 Google Analytics [分析] 和 Google Ads）会将“自动”显示为指标的唯一可用汇总类型。这些数据集已汇总，将可能庞大的数字列表缩减为单个值。所用的汇总可以很简单（例如求和或计数），也可以更复杂（例如百分位）。您无法将自动汇总的指标更改为其他汇总类型，因为这样做需要 Looker Studio 有权访问未汇总的原始数据。
您还会看到系统根据其他数据源（例如 Google 表格）将“自动汇总”应用于计算字段。在这种情况下，聚合是公式中使用聚合函数（例如 AVG(Price)）的直接结果。同样，您无法在此处更改自动汇总，因为这会与 AVG 函数的输出冲突。
[[["易于理解","easyToUnderstand","thumb-up"],["解决了我的问题","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["很难理解","hardToUnderstand","thumb-down"],["信息或示例代码不正确","incorrectInformationOrSampleCode","thumb-down"],["没有我需要的信息/示例","missingTheInformationSamplesINeed","thumb-down"],["翻译问题","translationIssue","thumb-down"],["其他","otherDown","thumb-down"]],["最后更新时间 (UTC)：2025-07-31。"],[],[],null,["# Aggregation is the process of **reducing** and **summarizing** tabular data. For example, consider the list of numbers following:\n\u003e 100, 200, 300, 400, 500\n\nUsing this example, you can state the following facts that illustrate the concept of aggregation:\n\nThere are other ways you can aggregate data, including calculating the median, count distinct, quartiles, percentiles, etc.\n\nDimensions and aggregation\n--------------------------\n\nThe previous example is based on a single set of numbers, but that's almost never what you see in the real world. In the real world, your data is typically organized into dimensions and metrics. Dimensions provide a way to categorize and group your data, while metrics measure that data.\n\nIn Looker Studio, aggregation **always** takes place in the context of a set of dimensions. That set of dimensions can be:\n\n- Every dimension, which lets you see the raw data.\n- A subset of your dimensions, which lets you see data broken down (grouped) by the dimensions you select.\n- The empty set, which lets you see a summary of the entire dataset.\n\nFor example, here are the same five numbers presented as daily stock prices. *Date* and *Ticker* are dimensions, *Price* is a metric.\n\nYou can now use the dimensions to group the data in different ways. For example:\n\n**By Ticker**\n\n**By Date**\n\nIn the examples above, the metric values depend on what you want to know about the data. For example, to calculate the average price for each company, apply the Average aggregation in conjunction with the *Ticker* dimension:\n\nTo see how many companies had stock information on a given day, you would use the *Date* dimension and the Count aggregation:\n\nNow, consider what happens when you use both the *Date* and *Ticker* dimensions in the stock table:\n\nWhen you create a group that includes all the available dimensions, the result is identical to the original data. **This is still an aggregation,** just not an interesting one, since every aggregation gives the same result. In Looker Studio, if you make a table and show every dimension, you're still able to set the aggregation type but it won't do anything.\n\nAggregation in Looker Studio\n----------------------------\n\nThere are several ways to apply an aggregation method to your data in Looker Studio:\n\n**In the data source.** A field's default aggregation determines how that metric is displayed in charts. See [Default aggregation](#default-aggregation) for more information.\n\n**In a chart** . Report editors can override the default aggregation and apply a different one to the metric on a chart by chart basis. Learn how to [add and edit data in charts](/looker/docs/studio/edit-fields-in-your-reports).\n\n**In a calculated field** . You can use specific aggregation functions within a calculated field formula to produce aggregated metrics. [See the list of functions](/looker/docs/studio/function-list).\n\n### Default aggregation\n\nYou can apply the following default aggregations to fields in data sources.\n\n#### **Change the aggregation method**\n\nTo change the field's aggregation method, edit the data source, then use the **Default aggregation** drop-down menu..\n\n### Auto aggregation\n\nSome data sources, such as Google Analytics and Google Ads, show Auto as the only available aggregation type for metrics. These data sets are already aggregated, reducing a potentially massive list of numbers to single values. The aggregations used can be simple, like sum or count, or more complex, like percentile. You can't change Auto aggregated metrics to a different aggregation type, since doing so would require Looker Studio to have access to the raw, unaggregated data.\n\nYou'll also see Auto aggregation applied to calculated fields based on other data sources, such as Sheets. In this case, the aggregation is a direct result of using an aggregation function in the formula, such as `AVG(Price)`. Again, you can't change the Auto aggregation here, because that would conflict with the output of the AVG function."]]
