I checked those two tables and publishFrom and publishTo columns are Null for this custom page, however, in pages app, it did show the data and on left tree view, there is clock icon on the custom page indicating it's a scheduled page. Is there any other table storing this data and how to retrieve this value from my .net project? and which api of kentico? Thanks
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I found if I put a date time that is no later than Now time, it can be recorded in CMS_Document table. Otherwise the column will not be updated.