SELECT * FROM your_table WHERE data_dt = '__HIVE_DEFAULT_PARTITION__'; ok thank's for your reply ,i understand this example But my question is, in my Third SQL statement, using length() function in the select statement is effective and the result is 26, while in the first and second  SQL , why can't this record be filtered by length in the where statement when I use the length function on the partition key? Thank You ... View more