**Return value type**: If all input strings are VARCHAR type, the result is VARCHAR type too. If any one of input strings is NCHAR type, then the result is NCHAR.
**Applicable data types**: VARCHAR, NCHAR. Can't be used on tag columns. At least 2 input strings are requird, and at most 8 input strings are allowed.
**Applicable data types**: VARCHAR, NCHAR. At least 2 input strings are requird, and at most 8 input strings are allowed.