ISODATE

ISODate is a term used in two related contexts in computing. Broadly, it can refer to the ISO 8601 standard for representing dates and times in textual form, such as 2023-04-05T14:30:00Z. In practice, many programming environments use ISO 8601 strings to interchange date and time information.

In the MongoDB ecosystem, ISODate denotes a specific shell helper function that creates a BSON Date type. This function is part of the MongoDB shell and some drivers, and is used to construct a date value that is stored as the number of milliseconds since the Unix epoch in Coordinated Universal Time (UTC). When displayed, these values are typically shown in a format like ISODate("YYYY-MM-DDTHH:mm:ssZ").

Usage in MongoDB is straightforward: ISODate() can be called with an ISO 8601 date string to produce a date object representing that moment, or with no arguments to obtain the current date and time. The underlying storage remains a UTC-based timestamp, while the textual representation may be shown in ISO 8601-like form.

It is important to note that ISODate as a shell function is not part of the ISO 8601 standard itself; it is a convenience provided by MongoDB’s tooling. Different programming languages and drivers may implement date handling with similar concepts under different names, but the core idea is consistent: dates are represented internally as a precise point in time, often in UTC, with ISO 8601 strings used for input, output, or display. See also ISO 8601, BSON Date, and MongoDB.