>I was cleaning up my codebase the other day and noticed that more than a few people recommend indexing on ttoc() when a datetime field is concerned, instead of directly indexing on the column.
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>I never ran into any problems with indexing on the datetime type, but I am curious why "everyone" assumes its a no-no.
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>Thanks.

If your index is only on a data or time field, there is no need to convert it to character. To get proper ordering of a date field when combined with another field, the date field expression would be dtos(mydate). Using the dtoc() function on a date first orders by the month regardless of the year. For a datetime, you would use a second parameter -- ttoc(mydate, 1) -- which is similar to dtos() for a regular date field.