LISTAGG

LISTAGG(str_col[, delimeter]) [WITHIN GROUP (ORDER BY order_col)]

Concatenates all the strings in str_col within each group into a single string seperated by the characters in the string delimiter. If no delimiter is provided, an empty string is used by default.

Optionally allows using a WITHIN GROUP clause to specify how the strings should be ordered before being concatenated. If no clause is specified, then the ordering is unpredictable.

Returns '' if the input is all NULL or empty.