尝试在Pl/Sql中捕获异常处理

Question

在一个过程中,我想做逻辑单元1,如果失败则无关紧要,执行逻辑单元2

这似乎是一个典型的尝试捕获场景.但我怎么能在pl/sql中做到这一点？

create or replace
PACKAGE BUILD_PKG
AS
PROCEDURE reset_seq_and_truncate_tbl(
    p_seq_name   IN VARCHAR2,
    p_table_name IN VARCHAR2 );
END BUILD_PKG;
/
create or replace
PACKAGE BODY  BUILD_PKG
AS
BEGIN
PROCEDURE reset_seq_and_truncate_tbl(
    p_seq_name   IN VARCHAR2,
    p_table_name IN VARCHAR2 )
 IS
   l_val NUMBER;
 BEGIN
   BEGIN
     EXECUTE immediate 'truncate table ' || p_table_name;
   EXCEPTION 
        WHEN OTHERS 
        THEN dbms_output.put_line(SQLCODE);
   END;

   BEGIN
     EXECUTE immediate 'alter sequence ' || p_seq_name || ' increment by 1 minvalue 0';
   EXCEPTION 
        WHEN OTHERS 
        THEN dbms_output.put_line(SQLCODE);
   END; 
 END reset_seq_and_truncate_tbl;

END BUILD_PKG;

正如您所看到的,第二个异常块会导致问题.

Answer 1

EXCEPTION在BEGIN..END块中包含第二个.试试这种方式

PROCEDURE reset_seq_and_truncate_tbl(
    p_seq_name   IN VARCHAR2,
    p_table_name IN VARCHAR2 )
 IS
   l_val NUMBER;
 BEGIN
   EXECUTE immediate 'truncate table ' || p_table_name;
 EXCEPTION 
      WHEN OTHERS 
      THEN
      BEGIN
        dbms_output.put_line(SQLCODE);
        EXECUTE immediate 'alter sequence ' || p_seq_name || ' increment by 1 minvalue 0';
       --this would cause compilation error
       EXCEPTION 
            WHEN OTHERS 
            THEN dbms_output.put_line(SQLCODE);
     END; 
 END reset_seq_and_truncate_tbl;

更新以回应评论

PROCEDURE reset_seq_and_truncate_tbl(
    p_seq_name   IN VARCHAR2,
    p_table_name IN VARCHAR2 )
 IS
   l_val NUMBER;
 BEGIN
   BEGIN
     EXECUTE immediate 'truncate table ' || p_table_name;
   EXCEPTION 
        WHEN OTHERS 
        THEN dbms_output.put_line(SQLCODE);
   END;

   BEGIN
     EXECUTE immediate 'alter sequence ' || p_seq_name || ' increment by 1 minvalue 0';
   EXCEPTION 
        WHEN OTHERS 
        THEN dbms_output.put_line(SQLCODE);
   END; 
 END reset_seq_and_truncate_tbl;