void addCol ( std::string _name, TypeEnum type_size, void* _ptr, int row_num )
add one column into the Table with user-provided buffer pointer.
usage: tab.addCol(“o_orderkey”, TypeEnum::TypeInt32, tab_o_col0, 10000);
Parameters:
| _name | column name |
| type_size | size of the column element data type in bytes |
| _ptr | user-provided column buffer pointer |
| row_num | number of rows |