Generally .dbc files are classified in 2 types with accordance of their parametric value for fixed_size_dml which can be either true or false. If the value is false the database generates delimited types whenever possible(it recognizes null as zero-length string). In case of true it takes fixed length dml. Other parameters for .dbc files are:
dbms db_version db_home db_name db_nodes User & password case generate_dml_with_nulls fixed_size_dml treat_blanks_as_null oldstyle_emptystring_as_null fully_qualify_dml delimited_dml_with_maximum_size interface environment direct_parallel
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