Using Hint in Update or Select Statement...

Hi ,
I had an update statement that will get the data from the inline select statement,now where can i can keep the hint ,either in update statement or in Select statement...
Please let me know if my sample script is wrong or any better way to approach...Please assume that Salary table had millions of employee's salary records.
update emp
set salary = salary + (select /*+ full(a) parallel(a,4) */ salary from Salary
where experience > 5 and empno = 55 )
where empno = 85Thanks
Rede

The better approach would be to determine why you need a hint in the first place. If you're using a hint, that implies that the optimizer is choosing the incorrect plan when left to its own devices. That, in turn, implies that the statistics on your objects, the statistics on your system, your optimizer parameters, your session's optimizer settings or some other variable is incorrect. You're generally better off fixing the root problem than hinting every query.
In this specific case, the parallel hint is invalid because there is no table aliased A. The full hint is invalid for similar reasons. Plus, with the query you provided, if A was intended to be the SALARY table, it seems exceptionally unlikely that you really want to do a full scan on the salary table to look for what had better be a single row (otherwise your query would throw a "too many rows returned" exception).
Justin

Similar Messages

Hint in Update or Select Statement in an inline query ??

Hi ,
I had an update statement that will get the data from the inline select statement,now where can i can keep the hint ,either in update statement or in Select statement...
Please let me know if my sample script is wrong or any better way to approach...Please assume that Salary table had millions of employee's salary records.
update emp
set salary = salary + (select /*+ full(a) parallel(a,4) */ salary from Salary
where experience > 5 and empno = 55 )
where empno = 85Thanks
Rede

You would put the hint in the select statement as you have it, but it won't work until you alias your table name to "a" since that is how you are referencing it in the hint:
update emp
set salary = salary + (select /*+ full(a) parallel(a,4) */ salary from Salary a
where experience > 5 and empno = 55 )
where empno = 85
NOTE I added the "a" right after the Salary table name AND you can only do parallel updates on partitioned table, but the select will run in parallel to at least get the data for you quickly.
To answer your other question about syntax, it is incorrect and there are a lot of ways to write it but a straight forward way would be to use the merge statement
merge into emp e
using (select /*+ full(s) parallel(s,4) */ s.salary from salary s where s.experience > 5) s
on (e.empno = s.empno)
when matched then update
set salary = s.salary;

Use of the "updlock" hint with update and insert statements

I have inherited some stored procedures and am trying to figure out why the developers decided to use the "updlock" hint on many of the update and insert statements. I have looked around everywhere and have found only one explanation of why "update...with
(updlock)" can be useful, namely when a table has no clustered index:
http://www.sqlnotes.info/2012/10/10/update-with-updlock/ I have found nothing yet that mentions why "insert into...with (updlock)" might be used. I understand why the hint
might be useful on select statements in some cases, but if all of the tables have clustered indexes, is there any good reason to use it on update and insert statements?
Thanks,
Ron
Ron Rice

This form of deadlock error can occur on a table which has a clustered index.
If you are doing updates on a table which has a clustered index and that table also has a nonclustered index and the nonclustered index is used to find the row to update you can see this type of deadlock. For example create a table with a clustered
primary key index and a nonclustered index by running
Create Table Foo(PK int primary key identity, OtherKey varchar(10), OtherData int);
go
Insert Foo Default Values;
go 10000
Update Foo Set OtherKey = 'C' + Cast(PK As varchar(10))
Create Unique Index FooIdx On Foo(OtherKey);
That creates a table with 10000 rows, a clustered index and a nonclustered index. Then run
Begin Transaction
Update Foo Set OtherData = 1 Where OtherKey = 'C5'
That will use the FooIdx index to find the row that needs to be updated. It will get a U lock on the index row in the FooIdx index, then an X lock on the row in the clustered index, update that row, then free the U lock on FooIdx, but keep the X lock
on the row in the clustered index. (There is other locking going on, but to simplify things, I'm only showing the locks that lead to the deadlock).
Then in another window, run
Begin Transaction
Update Foo Set OtherData = 2 Where OtherKey = 'C5'
This will get a U lock on the index row in the FooIdx index, then try to get an X lock on the row in the clustered index. But that row is already exclusively locked, so this second window will wait holding a U lock on FooIdx row and is waiting for
an X lock on the clustered index row.
Now go back to the first window and run
Update Foo Set OtherData = 3 Where OtherKey = 'C5'
This will once again try to get the U lock on the FooIdx row, but it is blocked by the U lock the second window holds. Of course the second window is blocked by the X lock on the clustered index row and you have a deadlock.
All that said, I certainly do not routinely code my updates with UPDLOCK. I try to design databases and write code so that deadlocks will be rare without holding excessive locks. The more locks you hold and the longer you hold them, the more
blocking you will get and the slower your system will run. So I write code that if a deadlock exception occurs, it is properly handled. Then if too many deadlocks occur, that is the time to go back to the code to see what changes are needed to
decrease the number of deadlocks (one way to do that may be to get locks earlier and/or hold them longer.
But I wouldn't worry much about this form of deadlock. It is, in my experience, vary rare. I don't recall ever seeing it in a production environment.
Tom

Using pop-up value in select statement

Hello.
I want to select a value from a pop-up box and then use that value in a select statement for another pop-up. Is that possible?
The first pop-up is P39_PIIN_CALL but it is not recognized in the second pop-up when I use it in the select statemnt... select * from table where PIIN = :P39_PIIN_CALL. I get nothing back because it has no idea what :P39_PIIN_CALL is. I'm desperate and on a timeline.
Thanks,
Mark E

Hi,
After fetching the value from first popup the page should submit so that the value is availble to the second popup..
Edit the first popup.. and in HTML Form Element Attributes and enter onchange="doSubmit('MyRequest')"
Regards,
Shijesh

Limitations in using a function within a select statement

I have a function which retrieves various data elements from the
database and formats it accordingly. The data (varchar2)
returned could be in excess of 2,000 characters length.
I need to use the returned data as part of a view. I am able to
use the function in a "select" statement, but when I use it with
returned data in excess of 2,000 chars, I get the following
error:
ORA-06502: PL/SQL: numeric or value error
This error is occurring whenever the returned data is in excess
of 2,000 characters.
Is there an alternative method to what I am proposing, I have
tried alternative data types but if I am able to use it in a
"select" statement, I get the above error when the returned
length exceeds 2,000 chars.
Thanks
Peter

are u using oracle 7. varchar2 limit in 8 is 4000.

Use of cursors insted of select statements

could any one please explain what is the advantage of using cursors instead of simple select statements
thanks
siby

A benefit to using an explicit cursor rather than a select statement, is for the NO_DATA_FOUND exception. Its kind of like a free IF statment. IF no data is found, then stop.
if you write a select statement, and no data is returned, you SHOULD code for the NO_DATA_FOUND exception. Often people say, "i'll ALWAYS get a row returned". but you should always cover your code "just in case". so you must code an exception...
declare
v_var varchar2(1);
procedure do_something(p_parm varchar2) is
begin
null;
end do_something;
procedure log_error is
begin
null;
end log_error;
begin <<main>>
do_something('x');
begin <<selectblock>>
select dummy
into v_var
from dual
where dummy = 'a';
do_something(v_var);
exception
when no_data_found then
log_error;
end selectblock;
do_something (v_var||'abc');
end main;
if you use an explicit cursor instead, you don't need to code for the NO_DATA_FOUND. If an explicit cursor opens and finds no rows, there are simply no rows. of course, you don't need a loop if you expect only 1 row returned under normal circumstances.
BTW, don' forget that SQL%ROWCOUNT and your_cursor%ROWCOUNT are not initialized. There is a null, until a row is successfully fetched. therefore if no rows are returned at all, %ROWCOUNT is NULL.
declare
v_var varchar2(1);
cursor my_cur is
select dummy
from dual
where dummy = 'a';
procedure do_something(p_parm varchar2) is
begin
null;
end do_something;
procedure log_error is
begin
null;
end log_error;
begin << main>>
for cur_rec in my_cur loop
dbms_output.put_line('inside');
begin <<loop_block>>
if nvl(my_cur%rowcount,0) > 1 then
do_something(cur_rec.dummy);
else
log_error;
end if;
end loop_block;
end loop;
end main;
/

Problems with Hints in abap code to use an index in a Select statement

Hi,
I want to use an especific index in a select statement but I can´t get it. I use de next statement:
SELECT ltaklgnum ltaktanum ltakvbeln ltaptapos ltapnltyp ltappvqui
       FROM ltak AS ltak INNER JOIN ltap AS ltap
                        ON ltaktanum = ltaptanum
                        AND ltaklgnum = ltaplgnum
       INTO TABLE l_t_tanum_silo
       WHERE ltap~lgnum EQ ip_lgnum
         AND ltap~pquit EQ ' '
         AND ltak~lgnum EQ ip_lgnum
         AND ltak~kquit EQ ' '
         AND ltak~queue EQ ip_queue
         %_HINTS DB2 ''.
We have DB2 for Linux Unix and Windows 9.5 as DB system.
How can I fix this?
Thanks a lot.
Regards

The DB2 for Linux Unix and Windows is coded DB6 for SAP and not DB2
Look at the following OSS notes
- [Note 129385 - Database hints in Open SQL|https://service.sap.com/sap/support/notes/129385]
- [Note 150037 - Database hints in Open SQL for DB6 (DB2 for LUW)|https://service.sap.com/sap/support/notes/150037]
- [Note 1270314 - DB6: DB2 9.5 Perf. degrad. for queries with INLIST clause|https://service.sap.com/sap/support/notes/1270314]
- [Note 868888 - DB6: Optimization Guidelines|https://service.sap.com/sap/support/notes/868888]
You should use a
SELECT ltak~lgnum ltak~tanum ltak~vbeln ltap~tapos ltap~nltyp ltap~pvqui
FROM ltak AS ltak INNER JOIN ltap AS ltap
ON ltak~tanum = ltap~tanum
    AND ltak~lgnum = ltap~lgnum
INTO TABLE l_t_tanum_silo
WHERE ltap~lgnum EQ ip_lgnum
    AND ltap~pquit EQ ' '
    AND ltak~lgnum EQ ip_lgnum
    AND ltak~kquit EQ ' '
    AND ltak~queue EQ ip_queue
%_HINTS DB6 '<IXSCAN TABLE=''LTAP'' INDEX=''"LTAP~M"'' />'.
In note 868888 there is a sample for a join.
SELECT A~TABSPACE
FROM TADB6 AS A
JOIN IADB6 AS B ON A~TABART = B~TABART
%_HINTS DB6 '<NLJOIN><IXSCAN TABLE=''IADB6'' />'
        DB6 '<IXSCAN TABLE=''TADB6'' /></NLJOIN>'.
Regards

How to use bind variable in this select statement

Hi,
I have created this procedure where table name and fieldname is variable as they vary, therefore i passed them as parameter. This procedure will trim leading (.) if first five char is '.THE''. The procedure performs the required task. I want to make select statement with bind variable is there any possibility to use a bind variable in this select statement.
the procedure is given below:
create or replace procedure test(tablename in varchar2, fieldname IN varchar2)
authid current_user
is
type poicurtype is ref cursor;
poi_cur poicurtype;
sqlst varchar2(250);
THEVALUE NUMBER;
begin
     sqlst:='SELECT EMPNO FROM '||TABLENAME||' WHERE SUBSTR('||FIELDNAME||',1,5)=''.THE ''';
     DBMS_OUTPUT.PUT_LINE(SQLST);
OPEN POI_CUR FOR SQLST ;
LOOP
     FETCH POI_CUR INTO THEVALUE;
          EXIT WHEN POI_CUR%NOTFOUND;
          DBMS_OUTPUT.PUT_LINE(THEVALUE);
          SQLST:='UPDATE '||TABLENAME|| ' SET '||FIELDNAME||'=LTRIM('||FIELDNAME||',''.'')';
          SQLST:=SQLST|| ' WHERE EMPNO=:X';
          DBMS_OUTPUT.PUT_LINE(SQLST);
               EXECUTE IMMEDIATE SQLST USING THEVALUE;
END LOOP;
COMMIT;
END TEST;
Best Regards,

So you want to amend each row individually? Is there some reason you're trying to make this procedure run as slow as possible?
create or replace procedure test (tablename in varchar2, fieldname in varchar2)
authid current_user
is
   sqlst      varchar2 (250);
   thevalue   number := 1234;
begin
   sqlst := 'update ' || tablename || ' set ' || fieldname || '= ltrim(' || fieldname || ',''.'') where substr(' || fieldname
      || ',1,5) = ''.THE ''';
   dbms_output.put_line (sqlst);
   execute immediate sqlst;
end test;will update every row that satisfies the criteria in a single statement. If there are 10 rows that start with '.THE ' then it will update 10 rows.

How to use variables in an sql select statement.

Hi, I have seen examples using the update, but nothing using a select statement.
I have four variables I am getting from drop down menus in my JSP I set the user selected items to strings.
How would I create the select statement like this:
.String XName = request.getParameter("UserInputX");
rsInResult = stmtInResult.executeQuery("SELECT ColumxX FROM TableZ WHERE ColumnX = XName")Obviously it tries to read "XName" as a column and of course can't find it, how would I set it up to have it see the Value of XName and not the literal XName.

read this:
rsInResult = stmtInResult.executeQuery("SELECT ColumxX FROM TableZ WHERE ColumnX = '"+XName+"')
{code}
better way is PreparedStatement:
{code}
     // example code to change password to an user in the USERS table
     String newPWD = "my password";
     String user = "luxjava";
     PreparedStatement prepStat;
     String updatePWD = "UPDATE LOGISTIC.USERS "+
                              "SET logistic.users.password = ? "+
                              "WHERE logistic.users.username = ?";
     prepStat = ql.conDb.prepareStatement(updatePWD);
     prepStat.setString(1, newPwd);
     prepStat.setString(2, user);
     int zeroNotFound = prepStat.executeUpdate();
     if (zeroNotFound==0)
          ql.conDb.rollback();
          prepStat.close();
     else
          ql.conDb.commit();
          prepStat.close();
{code}
... use the SQLException to capture errors

For update in select statement

i have a table which store data in a clob. sometimes user forget to add and extra carriage return after last line. so i am doing the following to modify the clob
SELECT file_content INTO lv_lob FROM files WHERE id = p__id FOR UPDATE;
dbms_lob.writeappend(lv_lob,2,C_NEW_LINE);
C_NEW_LINE CONSTANT VARCHAR2(2) := Chr(13)||Chr(10);
'for update' should only lock that specific row since id is a pk key in the table.
i have two front end screen where people upload file. a unique id is generated for each file and the data with id inserted in the table. user can upload file from the two different screen at same time.
the problem is that i am getting a 'resource busy and acquire with NOWAIT specified' error. i don't know why if every file i upload belongs to different row.
anybody knows why i would get this error and how can i solve it?

How are you generating the unique ID? Are you using a sequence? Or are you using something that forces serialization?
Where in the program flow are you adding the extra carriage return?
Is it this SELECT statement that is throwing the error? Or is it being thrown somewhere else?
Justin

Can we use is null in our select statement in ABAP program

hi,
I want to use 'is nul' or 'not null' in select statement of my ABAP program for any field. I have written below query but I am getting sy-subrc = 4 and getting no data. Can anyone resolve this.

Hi,
I think you've posted your question on the wrong forum. This is the SAP Business One development forum which is not part of ERP and doesn't include any ABAP or Netweaver programming.
For a list of forums please see here:
http://forums.sdn.sap.com/index.jspa
Kind Regards,
Owen

Can use place holder (?)in select statement.

Is it possible to have have a place holder in my select clause or it is possible to have only in where clause?
Please find the below query I am having place holder in select statement emp_id=? nit it is throwing an error for me.
select * from(select myrows.*, rownum rn from(select acc as account, es as identity,address as street_address
state as stae,select id from mytable where emp_id=? as my site from myview
where ert_id=? and chek=?
I am getting an error ORA-00936:     missing expression is it possible to have a place holder in select statement
Please help me on this.
Regards,
BA

user575682 wrote:
Is it possible to have have a place holder in my select clause or it is possible to have only in where clause?
Please find the below query I am having place holder in select statement emp_id=? nit it is throwing an error for me.
select * from(select myrows.*, rownum rn from(select acc as account, es as identity,address as street_address
state as stae,select id from mytable where emp_id=? as my site from myview
where ert_id=? and chek=?
I am getting an error ORA-00936:     missing expression is it possible to have a place holder in select statement
Please help me on this.
Regards,
BAfor clarity and easy to be read i attempted to rearrranged your code and this is what it will look like:
select *
from (select myrows.*, rownum rn
          from (select acc as account,
                       es as identity,
                       address as street_address
                       state as stae,
                       select id
                  from mytable
                 where emp_id = ? as my site from myview where ert_id=? and chek=?apparently the syntax is not correct and by that you are missing some comma in your column, ? question mark symbol will not be recognize, and some ')' closed parenthesis.
are you using a report builder that you want to use a placeholder column?

Usgent: using jsp date in sql select statement

i have something like this:
String day;
String month;
String year;
select * from event where date = xxx
where xxx is supposed to be obtained from the strings (day, month, year) and changed into a format that can be compared to in the select statement.
what should xxx be?
thks as lot cos i ahe been figuring out for very long.

Use PreparedStatement and SimpleDateFormat:
String year = "2002";
String month = "9";
String day = "12";
String sDate = day + "/" + month + "/" + year;
SimpleDateFormat df = new SimpleDateFormat("M/d/yyyy");
Date dDate = df.parse(sDate);
Connection con = DriverManager.getConnection(user, pw);
PreparedStatement ps = con.prepareStatement("SELECT * FROM event WHERE date = ?");
ps.setDate(1, dDate);
ResultSet rs = ps.executeQuery();
while (rs.next()) {
rs.close();
ps.close();
con.close();

Using a varchar field to select statement

Hi all
I have a single row and single column table
T(command varchar2(4000))
and the row is
sno,name
And I have another table T1(sno number,name varchar)
Now can any body tell how can i use command column in table T to query T1 to get sno,name from T1
I am looking for a select statement like this
select (select command from T) from T1;
but it is printing out the data in T i mean sno, name
This is a copy of thread Selecting output of a select statement
but explained more clearly
Thanks,
ganesh.

I don't know why your tables are designed like this but what I think you want to do is join T1 with the data in T.
select sno, name from T1
where sno in (select substr(command,0,instr(command,',')-1) from T)
and name in (select substr(command,instr(command,',')+1) from T);
substr returns a string up to a position
instr returns the position of a string
and the other post you refer to as about as confusing as your one.

Benefit of using store procedure instead of select statement to pull data into biztalk

I was wondering why store procedure is more beneficial than using select statement to pull data into biztalk?

In addition to the above two points, in case if there is a change in logic of stored procedure, you only need to modify the stored proc and the applications calling/using it may be left intact.
Also, stored procedures are complied code so performance is better and safe too.
Thanks,
Prashant
Please mark this post accordingly if it answers your query or is helpful.

Using Hint in Update or Select Statement...

Similar Messages

Maybe you are looking for