dbms_output语句中的单引号？

Question

我需要在dbms_output语句中包含单引号。我试过这个：

 dbms_output.put_line('\''first_name||'\'');

此处first_name为 variable ;我需要在单引号内显示​​它。

Answer 1

你可以通过加倍来逃避：

 dbms_output.put_line('''' || first_name || '''');

或使用q-quote机制：

 dbms_output.put_line(q'[']'||first_name||q'[']');

例如：

SQL> var b1 varchar2(30)
SQL> exec :b1 := 'this is a test';

PL/SQL procedure successfully completed.

SQL> exec  dbms_output.put_line(q'[']'||:b1||q'[']');
'this is a test'

PL/SQL procedure successfully completed.

SQL> exec  dbms_output.put_line(''''||:b1||'''');
'this is a test'

PL/SQL procedure successfully completed.

SQL> exec  dbms_output.put_line(chr(39)||:b1||chr(39));
'this is a test'

PL/SQL procedure successfully completed.

Answer 2

请注意，这仅适用于PL / SQL，必须处于活动状态。

begin
DBMS_OUTPUT.PUT_LINE('DELETE FROM MYTABLE WHERE MYFIELD <> ''A'';');
end;
/

假设您想要匹配CHAR＆＃39; A＆＃39;。