[[["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):2025-07-30。"],[],[],null,["DATETIME_SUB\n============\n\nSubtracts a specified time interval from a date.\n\nSample usage\n------------\n\n`DATETIME_SUB(Order Date, INTERVAL 1 WEEK)`\n\nSyntax\n------\n\n`DATETIME_SUB( `\u003cvar translate=\"no\"\u003edatetime_expression\u003c/var\u003e`, INTERVAL `\u003cvar translate=\"no\"\u003einteger\u003c/var\u003e` `\u003cvar translate=\"no\"\u003epart\u003c/var\u003e` )`\n\n### Parameters\n\n- \u003cvar translate=\"no\"\u003edatetime_expression\u003c/var\u003e - a Date or a Date \\& Time field or expression.\n- \u003cvar translate=\"no\"\u003einteger\u003c/var\u003e - a whole numeric field or expression representing the number of parts to subtract.\n- \u003cvar translate=\"no\"\u003epart\u003c/var\u003e - the unit of time measurement to subtract. DATETIME_ADD supports the following values for `part`:\n - `MICROSECOND`: available for Date \\& Time fields or expressions.\n - `MILLISECOND`: available for Date \\& Time fields or expressions.\n - `SECOND`: available for Date \\& Time fields or expressions.\n - `MINUTE`: available for Date \\& Time fields or expressions.\n - `HOUR`: available for Date \\& Time fields or expressions.\n - `DAY`\n - `WEEK`: This date part begins on Sunday.\n - `ISOWEEK`: Uses [ISO 8601 week](https://en.wikipedia.org/wiki/ISO_week_date) boundaries. ISO weeks begin on Monday.\n - `MONTH`\n - `QUARTER`\n - `YEAR`\n - `ISOYEAR`: Uses the [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) week-numbering year boundary. The ISO year boundary is the Monday of the first week whose Thursday belongs to the corresponding Gregorian calendar year.\n\nReturn data type\n----------------\n\nDate \\& Time\n\nExamples\n--------\n\nNotes\n-----\n\nThis function is not available for compatibility mode date types.\n\nSpecial handling is required for `MONTH`, `QUARTER`, and `YEAR` parts when the date is at (or near) the last day of the month. If the resulting month has fewer days than the original Date or Date \\& Time's day, then the result day is the last day of the new month.\n\nRelated resources\n-----------------\n\n- [Dates and times](/looker/docs/studio/dates-and-times)\n- [Calculated fields](/looker/docs/studio/about-calculated-fields)\n- [Looker Studio function list](/looker/docs/studio/function-list)"]]