The query function then checks

[kexej28769@nongnue]

Normally we would hide the first row, but this appears to show you a formula that looks at all categories and filters them to only those where the checkbox next to them is checked. If there is none, then in RegEx-speak "(\d|Deadline)" means "either a number, or the word Deadline" (anything in our list), because the vertical pipe "|" means "or" and "\d" means "number."

If there is a tick next to one or more categories, switzerland number data formula will return those items, separated by “|.” This, again, means “or” in RegEx.

=if(countif(C3:C,True)>0,CONCATENATE("("JOIN("|", FILTER(B3:B,C3:C=True,not(isblank(B3:B))))")"),"(\d|Deadline)")
Then in cell E3 we have the query formula. The reason we use =query here and not =filter is because we need to search for things in more than one column. The filter can only handle one column at a time.

A first six columns of our original Gantt chart, each time looking for numbers in any category that we have marked (conditional formatting hides that category numbers are in this original Gantt , they are the same color as the cell shading). When no checkbox is checked, it returns anything that falls into any category in the next six planned months. Once we start ticking checkboxes, it will only return items in the next six planned months that are in one of our selected categories.

=query('Gantt view'!D1:1056,"SELECT D, E, F, G, H, I, J WHERE D <> '' AND (E matches '"&B1&"' OR F matches '"&B1&"' OR G matches '"&B1&"' OR H matches '"&B1&"' OR I''&B'""&B matches ""&B1""