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Dropping an alias invalidates a prepared update statement if the latter statement uses the alias. Statement dependency system A searched update statement depends on the table being updated, all of its conglomerates units of storage such as heaps or indexes , all of its constraints, and any other table named in the WHERE clause or SET expressions. Dropping or adding triggers on the target table of the update invalidates the update statement.
A reader, August 20, - pm UTC. So, is it possible for writing such updates when the lookup table is an inline view? When we can make sure programatically that the lookup table ie. I will appreciate if you can show me how to rewrite the above sql the other way using where exists logic.
Sorry for posting incorrect sql earlier. If you want I can give you the create table ddls. August 21, - am UTC. Thanks for your time, but A reader, August 22, - pm UTC. That is not what is required. I am not updating the same value to all the rows as it is being done in this query. Actually I tried to rewrite the query earlier based on the approach of using the same query twice, once in the update statement and once in the where exists clause.
But since, the update has to be based on the join, I could not do it. Hope you understand what I am saying.. I think it is not possible to re-write this query using where exists properly. We have to use either merge, or the hint in 8.
Any comments? August 22, - pm UTC. Elapsed: August 23, - pm UTC. I did not. A reader, August 24, - am UTC. You have a join condition on customer. I thought you missed it, so I just added it. August 24, - am UTC. Thanks Tom, I got it now Sorry for "doubting" your solution And sorry for not providing you enought info, my create tables are very big some have hundreds of fields.
And we are doing it twice, once in the update clause and once in the where exists. Will therebe multible FTS on customer due to this? I looked at the plan and found only one FTS on my small test table, I will let you know how it goes in the real tables. Thanks again for your patience and perseverance. August 24, - pm UTC. Could you please explain the following? August 25, - am UTC. A reader, September 19, - pm UTC. Tom, There is a table with rows. Primay key on 1 column.
These 0s were replaced to nulls. The of indexes on the table is 8. All of them except pk unique are nonunique. Columns A, B also include. Not C Estimated time for the operation with an unknown sql is 90 minutes. It however took around 3 hours. Could you shed some light?
Indexes were not disabled before the operation. Only update triggers were disabled. I donot think any kind of tracking is used. September 19, - pm UTC. Tom, Unknown is the sql that somebody used. It is probably an update statement. That person estimated the operation would take 90 minutes. But it took a lot longer.
It took about 3 hours. Tracking is something like tkprof if i am not wrong. My questions: 1. Could a plain update statement be issued here which changes 0s to nulls. If not what should be used? What are the factors that need to be considered before doing an update like that?
How long should the update from the info that you have might take? I want to know if it is something that could be done in 10 mins, 20 mins September 20, - am UTC. I thought it would take an hour to get somewhere. I took an unknown route. It took me lots longer than I thought I wonder It'll be a function of how long it takes to full scan table T. It'll be a function of the load on your system. It'll be a function of the degree of contention. A little over a minute. Pls help me to resolve this prob.
Thanks a lot!! November 09, - pm UTC. Thanks for your quick response. November 10, - am UTC. December 03, - pm UTC. Thanks for the ealier answer. Am I going to have a problem? December 04, - am UTC. December 07, - am UTC. Yes, But since i had third table also so just wanted to make things myself clear. December 08, - am UTC. March 07, - am UTC. Hi I was stupid, thank you. Hi Tom, thaks for your valuable help on this web site. Hope you can help me with this update.
You said in the above example : "it is the inline view of the inline view. It seems it cannot "go up"!? How can I move that correlation to upper level?
Oracle 9. April 13, - am UTC. Which privilege am I missing? April 15, - pm UTC. Hi Tom, I am new to Oracle and I have a very strange and non standard requirement. T2 has records with data in C10 and C The copy should be such that the values in C11 should be approx or randomly into C3, basically just filling in values from C11 into C3 randomly since row counts do not match.
The output should be records in C3 with values randomly distributed from column C11 and not just one value into all records. I already spent 7 hours on this and no output. Tom, I am trying to fix bug and have test case perhaps you can help me.
I have complete brain fart. We use Oracle 9. September 15, - pm UTC. Real table has about 12 million rows. Also, explain how to "sort" this data. So I am having trouble coding to identify the change. Detecting a change is the fix that I supposed to provide.
There is no sorting right now but any kind will do, it is a downstream system being loaded in a batch sort of a data-garret I don't dare calling it data-warehouse. Thank you for looking into this. September 16, - pm UTC. Very useful, but there seems to be a problem updating self-joined tables Harry van Thor, December 13, - am UTC. This explains well the sort of update statement I would like to use, but I am wondering what the problem is with an update on a self-joined inline view for the test tables in this topic.
See below. December 13, - pm UTC. You'll use a correlated subquery for this or merge in 10g with just the update part. Hi Tom, Though the thread I understand, somehow I am unable to get things going in the following scenario. This is what the scenario is in the actual tables that the update is required. The primary key is only on SM and SL tables. December 21, - pm UTC. So if SM give 1 and 55 SL also will give the same.
Is there a way to go about? December 22, - pm UTC. Actually I was looking at doing this update with one single query instead of writing a block of code that I reproduce below. The merge statement worked well. Unable to figure out what's the difference between the merge and the update with the union clause! Also Tom, could you give more pointers to how to get the Correlated subquery update work for the case in question.
The merge has a different code path and extra checks to make sure a row is updated with a given of values ONCE, the update of a join doesn't have this sort of functionality. Thanks for the update query. Would this be considered as a Correlated update query? In the example you provided having a table without any rows, is it to show how to get the update with columns that have NULL values? December 23, - pm UTC. I meant to have one of the rows from t2 in t3 : my mistake - same result though. Von, February 27, - pm UTC.
Sorry if i am posting this in the wrong place This block doesnt finish at all.. Any ideas to make this run faster February 27, - pm UTC. I would look to the amount of resources you have on the machine - of which I have no idea. Heck, I don't even know the version after all.
A reader, February 27, - pm UTC. Tom thanks for the reply.. Looks great. Insert into third table Hi, My question is basically this: How can I insert records into a table based on joins from two other tables? Is it possible to do this from one statement? Any help will be much appreciated! April 26, - am UTC. I'm sorry your query is incorrect, but it would appear you already know how to insert data from two joined tables?
It is inserting the data, you just haven't written the query yet that returns the data you want. Normally, a join would have where table1. What you have done is: joined every row in CP to every row in TP kept those that had tac in some set and deviceId in some set I cannot really tell from your existing query what your goal was - sorry.
Hello Tom. I have the following trouble. Each of the tables table1 and table2 contains only the one row with ID Why the error ORA appears? July 12, - pm UTC. Not going to touch that hint, stop using it thankfully you used it wrong!!!! I'll show you how to do this legit - using documented features only. Tom, I am stuck with one update. Can you please suggest a method to do. So the net result should look like: a b c d e 3 30 ab 1 3 10 ab 2 3 10 ab 3 30 1 20 ab 4 3 20 bc 5 3 10 bc 6 3 10 bc 7 20 1 20 bc 8.
July 22, - pm UTC. You example does not show "sum" but "max". What happens if there are other values than 1 and 3 for b? And if d changes before b changes from 3 to 1? Your specifications are quite imprecise. July 23, - am UTC. I think Jamu's requirement is something like this: update t t1 set t1.
July 24, - am UTC. I'd rather have Jamu be a tad more specific before I take a guess :. Tom, When I update the table, the consistent gets is very high, how do I reduce it? And there is only one index on the table. July 27, - pm UTC. A reader, July 27, - pm UTC. Thanks for the response Tom! Here are the statistics: No. October 20, - pm UTC. My point, and I think I have one I'm just attempting to grasp WHY the original query set some values to null.
Merge on null column? Stephan, December 09, - pm UTC. I want to insert any missing rows into t1. If I try merging like this, merge into t1 using t2 on t2. December 10, - pm UTC. Sorry, I should have mentioned that I'm running 9. Also, I do understand that nulls are neither equal nor not equal to nulls - I understand why a straight merge isn't working.
But is there something I can use in its place? Thanks, Stephan. You must have got that up while I was trying to add more info. Thanks much. That did exactly what I was looking for.
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