The order of validation rules within a cell is important, as some rules may not function correctly—or at all—if applied in the wrong sequence.
It's important to note that, regardless of the order listed below, not all rules are compatible or may function together. This is simply a comprehensive list to help ensure they work correctly if used in combination.
Here is the order for the different validation rules:
readonly and/or optional and/or hidden and/or freeze and/or ignorena (in any particular order)
roundup[...] or rounddown[...]
Need to go with a "Formula"
Formulas, validity[...] or Charts parameters
Formulas would be for calculations or timespans between parentheses
validity[...] would be for the targeted fields and/or columns between parentheses for a validation
Charts parameters would be for charts to specify the X and Y values to target
Fills grid with [...]
Updated by [...]
Incremented by [...]
Show when [...] is [...]
Copy [...] when [...]
SET [...] when [...]
Invalid when [...] or Invalid when [...] if [...]