[[["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):2025-08-07。"],[[["\u003cp\u003eData Catalog uses technical metadata, including project information, asset details, and schema descriptions for BigQuery tables, alongside business metadata.\u003c/p\u003e\n"],["\u003cp\u003eBusiness metadata in Data Catalog includes tags, data stewards, and rich text overviews, with tags requiring specific syntax for searching.\u003c/p\u003e\n"],["\u003cp\u003eData stewards can be associated with data entries to provide further data entry information, even if they do not hold Google accounts, but they will require explicit IAM permissions to perform any project-related activities.\u003c/p\u003e\n"],["\u003cp\u003eBusiness metadata, such as data steward names or overview descriptions, is searchable without syntax, and if a deleted data entry is recreated within 32 days with the exact same identifier, the overview and data steward of the data entry are restored.\u003c/p\u003e\n"]]],[],null,["# Data Catalog metadata\n\nData Catalog handles two types of metadata: technical metadata\nand business metadata.\n\nTypes of technical metadata\n---------------------------\n\nAn example of technical metadata related to a data entry, such as a BigQuery table, can include the following attributes:\n\n- Project information, such as name and ID\n- Asset name and description\n- Google Cloud resource labels\n- Schema name and description for BigQuery tables and views\n\n| **Note:** The \"Last modification time\" of a BigQuery table resource refers to the modification time of the table's metadata, which might vary from the \"Last modified\" time listed in the BigQuery UI.\n\nTypes of business metadata\n--------------------------\n\nBusiness metadata for a data entry can be of the following types:\n\n- **Tags** applied to a data entry.\n\n To know more about tags, see [Tag and tag templates](/data-catalog/docs/tags-and-tag-templates).\n\n|\n| **Preview**\n|\n|\n| This feature is subject to the \"Pre-GA Offerings Terms\" in the General Service Terms section\n| of the [Service Specific Terms](/terms/service-terms#1).\n|\n| Pre-GA features are available \"as is\" and might have limited support.\n|\n| For more information, see the\n| [launch stage descriptions](/products#product-launch-stages).\n\n- (Preview) **Data stewards** associated with a data entry. A data steward for a\n data entry can be contacted to request more information about the data entry. A\n data steward does not require a specific IAM role. You can add a\n user with a non-Google email account as a data steward for a data entry. A data\n steward can't perform any project-related activity within the console, unless\n the user is provided with explicit IAM permissions.\n\n- (Preview) **Rich text overview** of a data entry that can include images,\n tables, and links.\n\n### Search for business metadata\n\nBusiness metadata is always linked to a technical metadata entry. Business\nmetadata is searchable without the use of any syntax. The only exception to this\nsearch is tags, which requires the use of [tag syntax](/data-catalog/docs/how-to/search-reference).\n\nThe following is a list of important information for the business metadata\nsearch for a Data Catalog data entry:\n\n- You can use email addresses or names of data stewards, and text from the data entry **overview** descriptions to search for relevant Data Catalog data entries.\n- Data Catalog doesn't support image search related to the rich text descriptions.\n- If you delete a data entry and then recreate it within 32 days with the exact same identifier, then the overview and data steward of the data entry are restored.\n\n### Limits for business metadata\n\nFor information about the limits for business metadata, see [Quotas and limits](/data-catalog/docs/resources/quotas).\n\nWhat's next\n-----------\n\n- [Apply](/data-catalog/docs/quickstarts/quickstart-search-tag) a tag, an\n overview, and a data steward to an entry.\n\n- Learn more about [tag templates and tags](/data-catalog/docs/tags-and-tag-templates) ."]]