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ORA-01002: fetch out of sequence
错误定位:
SQL> !oerr ora 01002
01002, 00000, "fetch out of sequence"
// *Cause: This error means that a fetch has been attempted from a cursor
// which is no longer valid. Note that a PL/SQL cursor loop
// implicitly does fetches, and thus may also cause this error.
// There are a number of possible causes for this error, including:
// 1) Fetching from a cursor after the last row has been retrieved
// and the ORA-1403 error returned.
// 2) If the cursor has been opened with the FOR UPDATE clause,
// fetching after a COMMIT has been issued will return the error.
// 3) Rebinding any placeholders in the SQL statement, then issuing
// a fetch before reexecuting the statement.
// *Action: 1) Do not issue a fetch statement after the last row has been
// retrieved - there are no more rows to fetch.
// 2) Do not issue a COMMIT inside a fetch loop for a cursor
// that has been opened FOR UPDATE.
// 3) Reexecute the statement after rebinding, then attempt to
// fetch again.
SQL>
查看pl sql:
declare
cursor emp_cursor is
select * from emp_text for update;
v_object_name emp_text%rowtype;
begin
open emp_cursor;
loop
fetch emp_cursor
into v_object_name;
if emp_cursor%found then
update emp_text
set object_id =
(emp_seq.nextval)
where object_name = v_object_name.object_name;
COMMIT;
end if;
exit when emp_cursor%notfound;
end loop;
close emp_cursor;
end;
正确写法:
declare
cursor emp_cursor is
select * from emp_text for update;
v_object_name emp_text%rowtype;
begin
open emp_cursor;
loop
fetch emp_cursor
into v_object_name;
if emp_cursor%found then
update emp_text
set object_id =
(emp_seq.nextval)
where object_name = v_object_name.object_name;
end if;
exit when emp_cursor%notfound;
end loop;
close emp_cursor;
COMMIT;
end;