数据新鲜度功能的运作方式是，将报告生成的查询和结果暂时存储在内存中。当 Looker Studio 遇到之前见过的查询，并且数据源的数据新鲜度阈值仍适用时，Looker Studio 会从内存中提供报告所需的数据。从内存中提取数据可以加快报告性能，并降低可能的查询费用或配额用量。一旦超出数据源的新鲜度阈值，或者发出之前未存储的新查询，Looker Studio 就会从底层数据集中提取数据。此过程适用于报告中的每个数据源。
[[["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)：2025-08-25。"],[],[],null,["# Manage data freshness\n\nMost data source types have a data freshness option (the exception to this is extracted data sources). This option lets you balance your need for up-to-date information against report performance and potential query costs or quotas. Each type of data source has its own default data freshness threshold, but you can adjust this threshold as needed. For example, if you are measuring ad performance on your site or app, you might find that daily data updates are sufficient. Reports that are based on social media analytics, on the other hand, may need their data updated multiple times a day.\n\nSet data freshness for a data source\n------------------------------------\n\nNew data sources that you create have a default refresh rate. To change the default data refresh rate, follow these steps:\n\n1. [Edit the data source](/looker/docs/studio/edit-a-data-source).\n2. In the data source configuration page, click **Data freshness**.\n3. Under **Check for fresh data**, select a new refresh option if one is available.\n4. Click **Set Data Freshness**.\n\nSee data refresh rates by connector\n-----------------------------------\n\nDifferent connectors support different data refresh rates, as shown in the following table. Note that Google marketing and measurement products, such as Google Ads, Google Analytics, Campaign Manager 360, Search Console, YouTube Analytics, and others, refresh every 12 hours. That rate can't be changed.\n\n\\* Default refresh rate\n\u003e **Tip** : Report editors can also [manually refresh the data in a report.](#refresh-report-data-manually).\n\nHow data freshness works\n------------------------\n\nData freshness works by temporarily storing in memory the queries and result generated by your reports. When Looker Studio encounters a query that it has seen before and the data freshness threshold for the data source still applies, Looker Studio serves the data that is needed by your report from its memory. Serving data from memory can both speed up your report performance and reduce possible query costs or quota hits. Once a data source's freshness threshold has been exceeded, or a new, previously unstored query is issued, Looker Studio fetches data from the underlying dataset. This process applies to every data source in your report.\n\u003e **Note** : While the data in your reports will not be older than the specified data freshness setting, there is no guarantee that the data will be served from memory for the entire freshness interval.\n\nHere are some examples of data freshness in action.\n\n### Example 1: View a default report configuration\n\nSay that your report connects to a BigQuery data source with the default data freshness setting of 12 hours. In this example, the default report configuration is as follows:\n\n- A table with some dimensions and metrics (for example, Date sold, Item color, Quantity)\n- A date range control set to the last 7 days\n- A filter control with no filters applied\n\nWhen you view this report for the first time, Looker Studio issues a query to fetch only the data that is needed to display the table. Looker Studio remembers that query and its results temporarily. The next time you view the default report within the data freshness threshold (12 hours), Looker Studio can use the data from its memory instead of fetching it from the data source.\n\n### Example 2: Apply filters\n\nIf you want to see only the red colored items for the previous quarter, you can adjust the date range and filter controls. Even though you're within the data freshness threshold, since this is a new query, Looker Studio goes to the data source to fetch that data. Looker Studio then remembers this new query and its results, if possible.\n\n### Example 3: Data freshness expiration\n\nWhen you next view your report, more than 12 hours have elapsed. Because the data freshness option for the BigQuery data source has expired, Looker Studio clears its memory for that data source, issues new queries, remembers those results, and resets the data freshness threshold for that data source.\n\n### Data freshness and data source credentials\n\nFor data sources that use Viewer's Credentials, each viewer of the report has their own data freshness settings. For example, if users A and B both view a report that is based on a data source that uses Viewer's Credentials, user A's queries don't affect the data freshness of the report for user B, and user B's queries don't affect the data freshness of the report for user A.\n\nFor data sources that use Owner's Credentials, all viewers of the report are governed by a single data freshness setting. (In effect, the owner of the data source credential is considered to be the viewer in all cases.) For example, if user A owns the data source credential and user B issues a query that causes Looker Studio to update the data in the report, then user A and all other viewers of the report will see the refreshed data.\n| **Caution:** BigQuery users should be aware that the usual [query costs](https://cloud.google.com/bigquery/pricing#query-pricing-details) apply whenever Looker Studio queries the underlying project. This includes queries that bypass Looker Studio's memory as well as manual and automatic data refreshes.\n\n### Data freshness and data source type\n\nData freshness works the same way for embedded data sources and reusable data sources. To maximize efficiency in terms of query costs and performance, consider using a reusable data source and Owner's Credentials. This will limit data refreshes to a single data source.\n\nRefresh report data manually\n----------------------------\n\nReport editors can refresh the data in a report at any time by following these steps:\n\n1. View the report.\n2. Click **More options** more_vert.\n3. Click **Refresh data** refresh.\n\nThese steps reset data freshness for every data source that is added to the report.\n\nSee data freshness for a report\n-------------------------------\n\nThe time and date of the last data refresh is displayed in the bottom left corner of the report. If the time shown is earlier than when you last made changes to the current report view, for example, by changing a date range or adding a filter, then all the charts on the page are being served from memory.\n\nData freshness and blends\n-------------------------\n\nFor a blended data source, the data freshness setting will be the minimum refresh time for all the data sources that are included in the blend.\n\nFor example, if you blend a Sheets data source that has a refresh time of 15 minutes with a BigQuery data source that has a refresh time of 4 hours, the resulting blended data source will have a refresh time of 15 minutes.\n\nData freshness and embedded reports\n-----------------------------------\n\nViewers can't manually refresh the data in an embedded report. (The data will refresh automatically when the data freshness threshold expires.)\n\nThe [auto refresh settings](/looker/docs/studio/manage-auto-refresh-for-a-report) on a report don't affect the data freshness of a data source. If a report triggers an auto refresh more frequently than the data source triggers a data refresh, the report returns data from memory.\n\nRelated resources\n-----------------\n\n- [Report settings](/looker/docs/studio/report-settings)\n- [Manage auto refresh for a report](/looker/docs/studio/manage-auto-refresh-for-a-report)"]]
