select column_list(column_create('a', 'val1'));
|
# +-----------------------------------------+
|
# | column_list(column_create('a', 'val1')) |
|
# +-----------------------------------------+
|
# | |
|
# +-----------------------------------------+
|
# 1 row in set (0.00 sec)
|
|
select length(column_list(column_create('a', 'val1')));
|
# +-------------------------------------------------+
|
# | length(column_list(column_create('a', 'val1'))) |
|
# +-------------------------------------------------+
|
# | 0 |
|
# +-------------------------------------------------+
|
# 1 row in set (0.00 sec)
|
|