Oracle中的“EXECUTE IMMEDIATE”命令问题

Question

我正在尝试在程序中执行此块...

 schema_nm := 'DEVL';
 plsql_block:='BEGIN ' || schema_nm || '.LIC_PKG.REMOVE(:x, :y); END;';
 BEGIN
     EXECUTE IMMEDIATE plsql_block USING  in_val1,in_val2;         
 END; 

当我尝试执行上述操作时，我看到了这个错误..

ORA-06550: line 1, column 7:
PLS-00201: identifier 'DEVL.LIC_PKG' must be declared
ORA-06550: line 1, column 7:
PL/SQL: Statement ignored

如果您遇到这种错误，请告诉我......

提前感谢您的帮助。