I have a question. If we have two scott sessions. I am updating a table EMP in session
1. It means it is exclusively locked.It cannot be used by session 2. Then can we use select command on table EMP in session
2.? This command should not work according to me. But it is working.
@ the end of the day means After date changes i need to populate the new row in Some of my tables with the previous date values with the new date.. In that time some other Transaction will Occur on those tables so we need to lock all the tables in that time..Even i tried by doing the Exclusive lock on the tables...
execute immediate 'LOCK TABLE CTR_SALES IN EXCLUSIVE MODE NOWAIT';
execute immediate 'LOCK TABLE CTR_STK_ASSIGN IN EXCLUSIVE MODE NOWAIT';
And how to run this function @ 12:00 in the midnight by scheduling.... And 1 more thing how to pick the recent (Transaction) row on that table. I tried from the rowid it's not working
I am having enq: TX - row lock contention in top wait event. it is occurring between 10pm - 2am.
We are having sqlloader job running every one hour(conventional path). But for the specific period of time i am getting "Global Enqueue Services Deadlock detected". Between 10-5. I analyzed related trace file it is make me little confusion.I found there are four insert query culprit for this locking. out of four sql , tow of them are ran by same SID, other two insert ran by same id. I got confused because how same sid locking them self. trace file below. during this period oracle maintenance window is active.
Trace file:
*** 2012-10-09 03:40:31.135
user session for deadlock lock 0x15365e060
sid: 1104 ser: 22256 audsid: 8797820 user: 49/iurth flags: 0x45
pid: 71 O/S info: user: oracle, term: UNKNOWN, ospid: 8601
image: oracle@sgh0909
client details:
[code]....
i have application where user logs and perform manipulation operation such as insert and update on database table.some time its possible that same user login twice, i just want to hold one session until and unless dml operation perform by another session gets complete.how to accomplish this in database level .
View 6 Replies View RelatedI have to find out the cause of a lock where a particular session with some serial no is causing a TX level lock for certain duration.
View 17 Replies View RelatedI am using Forms 6i and developed a Master Detail Oracle Form for Oracle EBS 11i application.
I was asked to write a pl/sql program so that.. When a user updating an existing record at the same time another user query the same record and try to update the same time, the record should be locked and a message should popup saying the record is being updated by another user.
How to enable tracing for sessions connected using shared servers ?
View 1 Replies View RelatedUnder what scenarios do we lock a table in the exclusive mode.
View 1 Replies View Relatedthere's a table with 3 columns oid, value, status in a scheme. Now i want this table to be used in an other scheme. So i used grant select to the other scheme so it could read the data. But now i want the column status for independent use of updates in the 2nd scheme. So i want the columns oid & value in one place (table in 1st scheme) and 2 places for status (in original table and in the 2nd scheme. I could create a status table in scheme 2 with oid and status and create an updatable view over table from scheme 1 and this status table - joined over oid. Sounds not too tough but if data is inserted in scheme 1 (all 3 colums) the status table in scheme 2 has no idea of this new data.I want to prevent using triggers or notifications.
View 23 Replies View Relatedwe know we can see lock mode held in session can be analysed using LM column in v$lock.But i confused in seeing LM column it all shows in numbers from 0 to 6.
eg
0,'None(0)',
1,'Null(1)',
2,'Row Share(2)',
3,'Row Exclu(3)',
4,'Share(4)',
5,'Share Row Ex(5)',
6,'Exclusive(6)')
how one can lock a particular row in a table.for example i have a employee table in which 50 records. now i want to lock only 10 records of the employee table.
View 8 Replies View RelatedWe had an issue with a PL/SQL package taking hours to run as a concurrent program. Database version is 10.2.0.4.0, running on Linux x86 64-bit. A tkprof'd trace file revealed the problem SQL statement to be a cursor. This one SQL statement would run for 3+ hours. I copied the SQL statement and ran it in TOAD and it completed in seconds, returning the exact same result set. To resolve the issue in the PL/SQL package I created a global temp table and ran the exact same SQL statement as an INSERT into the global temp table.
Again, instead of hours, the SQL statement completes in seconds. If I revert the change, it goes back to taking hours. I've attached the relevant sections of the tkprof showing the two SQL statements (identical other than the insert in front of one) and the resulting explain plans and performance data. I've always been under the impression that a cursor was a better option than a temp table and I've never run into a situation where the same SQL statement runs so much longer when executed as a cursor.
Attached File(s)
SQL_As_Cursor.jpg ( 274.02K )
Number of downloads: 7
Explain_for_SQL_As_Cursor.jpg ( 189.43K )
Number of downloads: 4
SQL_as_Insert.jpg ( 277.38K )
Number of downloads: 4
Explain_for_SQL_As_Insert.jpg ( 180.66K )
Number of downloads: 2
How to Release Lock on table ? ( without killing session )
create table x ( a number);
insert into x(a) values (1);
Lets lock table.
declare
cursor c is select * from x for update;
begin
open c ;
end;
[code]....
How can one lock a table manually?
View 7 Replies View RelatedI want to read 1 table. If the date is less than today, I want to update 4 other tables. I only want to do this update once a day.
While the 4 other tables are being updated, I want the other web users to pause for the update while this procedure runs.
Is there a better way to do this?
Here is what I have:
CREATE OR REPLACE PROCEDURE TEST_TODAY2 AS
-- to create the table
-- create table test_today(updated_date date);
-- insert into test_today(updated_date) values (sysdate-1);
-- select * from test_today;
cursor daily_update_cur is
select updated_date from test_today
for update of updated_date;
[Code]...
Please use {noformat}{noformat} tags before and after your code as described in the FAQ: {message:id=9360002}.
I've corrected it this time for you.
If you have 3 tables (yr09, yr10,yr11) one with 2009 data, 2010 and 2011 data respectively. And a view (vw_yr091011) with a "union all" on all three.
Question: Will the performance be same for the following two queries ?
Question: Will Oracle read all 3 tables in the view when we search for only one year ?
select count(*) from yr09
where year = 2009;
-- vs
select count(*) from vw_yr091011
where year = 2009;
The following link says yes, the performance remains the same.
Link: [URL]..........
when I tried on a volume of 14000 records. The count came out same but the view took 50 more sec. And the explain plan shows it accessed all three tables.
Can we lock data in global temporary table?
View 4 Replies View RelatedI want to know that what oracle server do to minimize the lock on parent table, when we use Index on foreign key column ?
View 2 Replies View RelatedI am using the Oracle 10g and I have question related to "for Update" clause.We have the data warehouse db, so no foreign key constraint between parent and child.We process the data files every hour, the condition is If we find the row in parent table then we go and look into child tables and perform insertion (if no corresponding record is present) or updation (if one corresponding record is present) in the child table.
The problem is If I run the two process simultaneously for the same kind of data, and if no record is present in the child table then it create the duplicate in child table.My question is if I use FOR Update clause while selecting the data in parent table will it lock the child table for any insertion or updation?
Ex- We have employee table for employee 1
In my data files I have the row for employee 1, so when I run the select query on employee table I found 1 row.The I look the child table "Salary" as there is no record for emp_id =1 in this table I insert the record for this
Emp_id Salary
1 500
The problem is if both the process run at same time then I get duplicate rows in child table
Emp_id Salary
1 500
1 500
we do not want the duplicate row insertion. Can I lock the child table during first process run
alter index test_idx1 shrink space;
I've heard that this statement causes a table lock but cant find any information on this.if it is so, is it a write lock or also a read lock of the table?
I have two design alternatives and need to understand how expensive (speed) is one of them against the other for a medium size table (100K-200K records):
create table xyz
(
f1 number not null,
f2 varchar2(20) not null,
f3 number not null,
f4 varchar2(50),
[code]....
the idea is to optimize the design by using a PK instead of the 3 keys and there is a debate that searching a unique index field(2nd scenario) is of the same speed than searching a PK field (1st scenario).
I ran into an issue in a project where a function is recreating an index-organized table by doing:Table Structure:
CREATE TABLE table_iot(
...)
ORGANIZATION INDEX
OVERFLOW ...;
Recreate Steps:
1) Populate global temporary staging table (gtt) with data
-- where gtt is staging for target index-organized table (iot)
2) Lock the target index-organized table (iot)
3) Copy old iot data to gtt
-- gtt now contains old and new data
4) Create new index-organized table (iot2) from gtt
-- iot2 now contains old and new data
[code]...
Because index-organized tables are primarily stored in a B-tree index, you can encounter fragmentation as a consequence of incremental updates. However, you can use the ALTER TABLE...MOVE statement to rebuild the index and reduce this fragmentation.The following statement rebuilds the index-organized table admin_docindex:
ALTER TABLE admin_docindex MOVE;
I read that the value EXCLUSIVE (REMOTE_LOGIN_PASSWORDFILE parameter) is supported for backward compatibility. It now has the same behavior as the value SHARED.So is the EXCLUSIVE value deprecated? Oracle Database Reference doesn't mention that.
View 6 Replies View RelatedI am using oracle 9i, and having trouble with updating a table.
I get ORA-00001(unique constraint) Error on executing the sql below; I know sql below is little strange( which use unique key in 'SET' statement) . but It worked on My Oracle Server. but it didn't on Client's.
why this error occurs or why this error did not occur on my PC,
[Update sql](key is CD and SDATE)
Update TBL1
set CD = 'A',
[Code]....
I am trying to write a control file that will read information from two INFILES and update two tables with the different information via SQL Loader. I am using Oracle 11g on Linux. i am not sure how to take the result from the first insert query and use it as input to the second insert query. Currently I have the following control file:
LOAD DATA
INFILE 'table1.dat'
INFILE 'table2.dat'
APPEND
INTO TABLE table1
WHEN tid='1'
FIELDS TERMINATED BY ","
OPTIONALLY ENCLOSED BY '"'
(pid "pid.nextval", p_fname, p_lname, tid)
[code]....
The pid in the second insert query should be taken from the pid generated in the first insert query. However, I do not know how to do this. Does SQL Loader run the first insert query for all entries in the table1.dat file and then the second insert query or will it do one record at a time? Here are my INFILES:
table1.dat
,John,Doe,1
,Joe,Smith,1
table2.dat
10,,abc,1,
11,,xyz,1,
The second field in table2.dat should be taken from the result of creating a record in the table1.dat. Is this something that can be achieved using SQL Loader? The first part of the control file is successful, I can see the table being updated with the contents on table1.dat, but the second query fails.
Oracle 11.2 - The goal is to create a trigger on table and anytime an update, delete or insert is done on the table, write values to a second table. I have the trigger and it works except it is not loading my col1/PK values. I understand I need to do a new/old value. Col1 is my PK on Table that I want to load anytime there is an update/delete/insert on the table. How do I code the old/new variable?
My
CREATE OR REPLACE TRIGGER TRIGGER_NAME
AFTER INSERT OR UPDATE OR DELETE
ON TABLE_NAME
FOR EACH ROW
DECLARE
v_col1 TABLE_NAME.COLUMN%TYPE;
BEGIN
[code]...
Let's consider such table that all rows fit into single block:
SQL> create table test as select rownum id, '$'||rownum name from dual connect by level <= 530;
Table created.
SQL> create index i_test on test(id);
Index created.
SQL>
SQL> begin
[code].....
why does approach with full scan take longer even if table occupies only one data block? PS. 11gR2
I have a job which runs the procedure below concurrently in 4 different sessions; It updates two tables.
PROCEDURE UPDATE_TAB_1_AND_TAB_2( traceIdTab IN pl_sql table,
individualIdTab IN pl_sql table,
fileSeqIdTab IN pl_sql table,
[Code].....
Each session is passed a sequence generated file ID; so the records processed in each session are completely different.
However, everytime this job runs, without failure, ONLY TWO sessions process concurrently, while the other two sessions are blocked. Once the first two have finished, then the remaining two sessions start work.
I have being monitoring the sessions on each run daily, and realized that the first two sessions processing are each holding a transaction exclusive lock on objects; hence blocking the other two sessions.
When I tried to find the objects that the two running sessions have a lock on, I cant seem to find anything by searching DBA_OBJECTS.object_id. However, when I look for the objects that are being waited on, its either a partitioned table or a partitioned index on either table_1 or table_2.
At first, I thought it was an ITL lock and after much analysis, I did not find anything which definitely pointed to an ITL lock. However, just to make sure, I increased the INITTRANS value from 2 to 5, but the problem did not go away.
At this point, I have applied all I know to understand the origin of the TX lock and how I can work around this situation, and decided to ask higher powers in Oracle for advise.
I am updating a table column which is xml datatype and am getting above error.Below is the process what i did. since the xml is too large i split them into small chunks.
DECLARE
conditionXML CLOB;
ls_xml_2 Clob;
ls_xml_3 clob;
ls_xml_4 Clob;
ls_xml_5 Clob;
ls_xml_6 clob;
ls_xml_7 Clob;
[code]...
pgit_policy is transaction table having producer code field.
pgith_policy is history table, on that table if any endorsement passed new records created with same polh_sys_id and increment on POLH_END_NO_IDX.
I am trying to update all records of the history table but its updating only higest POLH_END_NO_IDX only. i need to update all producer code.
update pgith_policy a
set a.polh_producer_code= (select b.pol_producer_code
from pgit_policy b
where b.pol_no=a.polh_no
--and b.POL_END_NO_IDX= a.POLH_END_NO_IDX and b.POL_END_SR_NO = a.POLH_END_SR_NO
and b.pol_producer_code is NOT NULL
and b.pol_class_code='10')
where a.polh_class_code='10'
and a.polh_producer_code is null
and a.polh_appr_dt between to_date('01-06-2011', 'dd-mm-yyyy') and to_date('30-06-2011', 'dd-mm-yyyy')