Difference between the pound signs and dollar signs during ibatis Mapping

In ibatis, We need to reference parameters when using sqlmap for SQL queries. The symbols # And $ encountered in parameter references are distinguished as, # can be compiled to match the types, $ does not match the data type, for example:

Select * from table where id = # ID #. If the field ID is of the dense type, # ID # indicates the 'id' type. If the ID is of the integer type, then # ID # is the ID type.

Select * from table where id = $ ID $. If the field ID is an integer, the SQL statement will not encounter errors, then the SQL statement should be written as select * from table where id = '$ ID $'