Both for formatting as well as parsing date, date formats are specified using a date format string. These consist of various tokens that indicate where a certain part of the date is to be placed or expected.
Note: for the "input_format_string" used in the facets.json file for Dataloaders (see Data Loader Facet Config Reference) the python date format is used. See http://strftime.org/ for reference on the supported directives). This also applies to the "Time format" option exposed as part of the "Map to facets" step when adding Data Sources from the UI (e.g. for Excel, CSV, ...)
Common Format Strings
The following table lists common format strings which are often used in data integration projects.
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Reference
The following table lists all supported directives which can be used in format strings. The example column is based on the sample string 2013-06-24T15:21:56.087821.
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This page can now be found at Date Format on the Squirro Docs site.