为什么DB2 CHAR（）函数返回'24：00：00'表示00:00:00的时间字段？

I'm querying DB2 on i (AS/400). A plain SELECT statement on a column with datatype of TIME returns 00:00:00, but when I use the CHAR() function it returns '24:00:00'.I'm querying DB2 on i (AS/400). A plain SELECT