topic Re: How can I clear the contents of a specific column in a specific data table? in Discussions

How can I clear the contents of a specific column in a specific data table?

xxvvcczz — Thu, 08 Jun 2023 16:29:03 GMT

I have an existing data table and I've updated rows in it, but now I want to have a function that just clears all the rows or sets them all to empty(); also would like it to be really fast because it's a very large table. I tried this but it's quite slow.

	Column( my_table, "MY_COL" ) << formula (empty());
	Column( my_table, "MY_COL" ) << Delete Formula;

Re: How can I clear the contents of a specific column in a specific data table?

brady_brady — Wed, 15 Mar 2023 01:53:31 GMT

Hi,

This should be faster; is it fast enough for your needs?

my_table[0, loc(my_table << get column names(string), "MY_COL")] = .;

For example:

Names Default To Here(1);

my_table = astable(J(1e5, 2, Random Uniform()));

my_table[0, loc(my_table << get column names(string), "Col1")] = .;

Re: How can I clear the contents of a specific column in a specific data table?

xxvvcczz — Wed, 15 Mar 2023 17:51:49 GMT

Thanks! This is much faster.