[英]How can I make an entire PL/SQL code block dynamic with bind variables?
背景
我正在嘗試制作可重用的PL / SQL過程,以將數據從一個數據庫移動到另一個數據庫。
為此,我正在使用動態SQL。
如果我將REPLACE與占位符一起使用,則該過程將完美執行。 但是,出於安全原因,我想使用綁定變量。
題
如何使整個PL / SQL代碼塊動態(帶有綁定變量)? 如果我使用REPLACE代替綁定變量,則可以正常工作。
如何復制
要將其復制到數據庫中,請直接創建以下過程:
create or replace procedure move_data(i_schema_name in varchar2, i_table_name in varchar2, i_destination in varchar2) as
l_sql varchar2(32767);
l_cursor_limit pls_integer := 500;
l_values_list varchar2(32767);
begin
select listagg('l_to_be_moved(i).' || column_name, ', ') within group (order by column_id)
into l_values_list
from all_tab_cols
where owner = i_schema_name and
table_name = i_table_name and
virtual_column = 'NO';
l_sql := q'[
declare
l_cur_limit pls_integer := :l_cursor_limit;
cursor c_get_to_be_moved is
select :i_table_name.*, :i_table_name.rowid
from :i_table_name;
type tab_to_be_moved is table of c_get_to_be_moved%rowtype;
l_to_be_moved tab_to_be_moved;
begin
open c_get_to_be_moved;
loop
fetch c_get_to_be_moved
bulk collect into l_to_be_moved limit l_cur_limit;
exit when l_to_be_moved.count = 0;
for i in 1.. l_to_be_moved.count loop
begin
insert into :i_table_name@:i_destination values (:l_values_list);
exception
when others then
dbms_output.put_line(sqlerrm);
l_to_be_moved.delete(i);
end;
end loop;
forall i in 1.. l_to_be_moved.count
delete
from :i_table_name
where rowid = l_to_be_moved(i).rowid;
for i in 1..l_to_be_moved.count loop
if (sql%bulk_rowcount(i) = 0) then
raise_application_error(-20001, 'Could not find ROWID to delete. Rolling back...');
end if;
end loop;
commit;
end loop;
close c_get_to_be_moved;
exception
when others then
rollback;
dbms_output.put_line(sqlerrm);
end;]';
execute immediate l_sql using l_cursor_limit, i_table_name, i_destination, l_values_list;
exception
when others then
rollback;
dbms_output.put_line(sqlerrm);
end;
/
然后,您可以執行以下操作:
begin
move_data('MySchemaName', 'MyTableName', 'MyDatabaseLinkName');
end;
/
由於許多原因(無法生成適當的執行計划,安全檢查等),Oracle不允許標識符綁定(表名,模式名,列名等)。 因此,如果確實有必要,唯一的方法是在進行某種形式的驗證后對這些標識符進行硬編碼(以防止SQL注入)。
如果我很了解,您可以嘗試通過在動態SQL中使用動態SQL來達到目的。
設定:
create table tab100 as select level l from dual connect by level <= 100;
create table tab200 as select level l from dual connect by level <= 200;
create table tabDest as select * from tab100 where 1 = 2;
這將不起作用:
create or replace procedure testBind (pTableName in varchar2) is
vSQL varchar2(32000);
begin
vSQL := 'insert into tabDest select * from :tableName';
execute immediate vSQL using pTableName;
end;
但這將達到目的:
create or replace procedure testBind2 (pTableName in varchar2) is
vSQL varchar2(32000);
begin
vSQL := q'[declare
vTab varchar2(30) := :tableName;
vSQL2 varchar2(32000) := 'insert into tabDest select * from ' || vTab;
begin
execute immediate vSQL2;
end;
]';
execute immediate vSQL using pTableName;
end;
我想您可以做得更簡單。
create or replace procedure move_data(i_schema_name in varchar2, i_table_name in varchar2, i_destination in varchar2) as
l_sql varchar2(32767);
begin
select listagg('l_to_be_moved(i).' || column_name, ', ') within group (order by column_id)
into l_values_list
from all_tab_cols
where owner = i_schema_name and
table_name = i_table_name and
virtual_column = 'NO';
l_sql := 'insert into '||i_destination||'.'||i_table_name||' select * from '||i_schema_name||'.'||i_table_name;
execute immediate l_sql;
end;
如果您擔心SQL注入,請查看包DBMS_ASSERT 。 該PL / SQL包提供了驗證輸入值屬性的功能。
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