SQL & PL/SQL :: Displaying N Number Of Rows From Large Result Set
Nov 29, 2012
I have a query that returns 11 Million rows but not all of them can be displayed in SQLDeveloper or DBVisualizer because of limited memory or other type of issues. I need to copy the entire result set to excel for further calculations.
Is there any way that i can select N number of rows out of my actual result set.
For example:
a) A result set contains 10 Million rows in total.
b) I want to display first 5 Million rows by executing a query
c) Then I want to display the remaining 5 Million rows by executing the query again with any parameter changes.
So all I want is to extract the rows of my actual result set in two or more executions, depending on the number of rows.
Consider tables A,B,C,D,E,F. all are having 100000++ records Tables B,C,D are dependent on table A (with foreign key constraint). When I am deleting records from all tables, table B,C,D are taking max 30-40 seconds while table A is taking 30-40 mins. All tables are having indexes.
Method I have used:
1. Created Temp table
2. then deleted all records from B,C,D,E,F for all records in temp table for limit of 500. delete from B where exists (select 1 from temp where b.col1=temp.col1);
3. Why it is taking too much time for deleting records in table A.
Is there any thing that during deleting data from such master table, it is referring to all dependent tables even if dependent data is not present ?
I was asked in a telephone interview about committing a delete ( a few million rows)in an oracle log table which had a trillion rows in total. He said that delete took 2 days.
Then he asked me if then commit is performed(assuming a huge rollback segments are allocated) how long does it take for that commit .
In form i call a record from database table through execute_query. i have lov on ITEM_NO
i want to display on that form, no. of records of ITEM_NO which i select from the list. like if i have 10 records with item_no which i select from list is must show 1/10.
if i press the down arrow it should show next record of the same item_no.
POWER(47.3616, 27.1261) returns: 2.80403309600359E45 which causes "number precision too large" error in my variable which is defined as NUMBER(20,20).
I've tried ROUNDing and TRUNCing the product, but still get the same long output. The only thing that seems to work is SUBSTR.
Is that the ONLY way to deal with this? It seems like there would be a better way or is there another type I should use these super long decimal results?
SQL> SELECT POWER(47.3616, 27.1261) AS Exp_Val 2 FROM dual; EXP_VAL ---------- 2.8040E+45 SQL>
where I have to display the value of current cell in next following cells.The table structure is as follows :
ttdate - date individualplanid - varchar(10); - train number sch_deptime - number(8); - scheduled departure time in milli seconds sch_arrtime - number(8); - scheduled arrival time in milli seconds stn - varchar(10); - station short name dep_delay - number(8); - dep delay in milli seconds arr_delay - number(8); - arr delay in milli seconds
The delay is filled continuously by application software continuously.I want to make a query where I want a calculated field which does the prediction of train arrival on coming stations. This shall be done as the delay + sch_deptime for all the next stations. Following is a dataset :
The last column (EAT) is calculated one. It shall be like as the dep_delay is updated the EAT for the following records shall be sch_deptime + dep_ delay. I did was something like this. The calculated field is cum_depdelay which is only the delay ( not sch_deptime + dep_delay ).
select ttdate,individualplanid td,station,sch_deptime,sch_arrtime,act_depdelay, sum(act_depdelay) over ( partition by individualplanid order by sch_deptime rows between current row and unbounded following ) c_depdelay from logtime where ttdate='14-Mar-2011' and individualplanid='BO646' order by sch_deptime,sch_arrtime; [code]...
I have created a function that is used for splitting a comma separated string & give the output in tabular form.here is the function
Here I have used CLOB as my input string will be huge(greater than max limit of varchar2)
CREATE OR REPLACE TYPE SPLIT_TBL_CLOB AS TABLE OF CLOB; CREATE OR REPLACE FUNCTION CSVTOSTRING_CLOB ( P_LIST CLOB, P_DEL VARCHAR2 := ',' ) RETURN SPLIT_TBL_CLOB PIPELINED
[code]....
But here I am facing 2 problems.
1. The function is not accepting a large string & I am getting the error
I need to export large number of records from select into the text file. It's about 2milion records.I can do it by PLSQL (see below) where executing of process takes time too much. How to export to text file faster?
We are facing one issue on one of the database. The database is generating large trace files(14000) from last two days. That consumes around 15G space on the disk. And the content of the trace files is not having any meaningful message to debug:
*** TRACE DUMP CONTINUED FROM FILE /apps/oracle/admin/fs90uat/bdump/fs90uat_p050_23966.trc ***
... (Many lines with above message)
The alert log is having one repeated error yesterday:
Thu May 6 22:00:03 2010 Errors in file /apps/oracle/admin/fs90uat/bdump/fs90uat_j000_11811.trc: ORA-12012: error on auto execute of job 2647927 ORA-04063: ORA-04063: package body "ORACLE_OCM.MGMT_DB_LL_METRICS" has errors ORA-06508: PL/SQL: could not find program unit being called: "ORACLE_OCM.MGMT_DB_LL_METRICS" ORA-06512: at line 1
The corresponding trace file is having error:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options ORACLE_HOME = /apps/oracle/product/10.2.0/db_1 System name: SunOS Node name: corpqadb30 [Code] .......
I have a report with single row having large number of columns . I have to use a scroll bar to see all the columns. Is it possible to design report in below format(half columns on one side of page, half on other side ofpage :
Column1DataColumn11DataColumn2DataColumn12DataColumn3DataColumn13DataColumn4DataColumn14DataColumn5DataColumn15DataColumn6DataColumn16DataColumn7DataColumn17DataColumn8DataColumn18DataColumn9DataColumn19DataColumn10DataColumn20Data I am using Apex 4.2.3 version on oracle 11g xe.
For obscure test purposes I need to modify an existing SQL query to emit the rows N times instead once. I'm aware of the possibility to "UNION ALL" the query with itself to get the all rows twice.
But as I require the resulting rows to be emitted around ten to hundred times this approach doesn't seem sensible to me. Not to speak of the missing possibility to parametrize the number of "repetitions".
What is the easiest way to add 2 rows together? I need this results set below as is except I need rows with activity codes 0 and 30 to be merged together into Activity Code 0. So, Regular hours would be 7466.75. Do I need to do a Union or is there a more elegant solution?
My current sql results set looks something like this:
Activity Code Activity Code Desc REGULAR OT NONPROD DEPARTMENT 0 0: Business As Usual 7409.25 305.5 1603.25 Information Technology 10 10: Special Projects 190.75 17 0 Information Technology 20 20: Strategic Initiatives 1067 52 0 Information Technology 30 0: Business As Usual 57.5 0 0 Information Technology
and I want my new results to look like this:
Activity Code Activity Code Desc REGULAR OT NONPROD DEPARTMENT 0 0: Business As Usual 7466.75 305.5 1603.25 Information Technology 10 10: Special Projects 190.75 17 0 Information Technology 20 20: Strategic Initiatives 1067 52 0 Information Technology
Oracle version details BANNER Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - Production PL/SQL Release 11.1.0.7.0 - Production CORE 11.1.0.7.0 Production TNS for 32-bit Windows: Version 11.1.0.7.0 - Production
I am trying to retrieve all rows with the date of May 23rd, 2008. Our data is stored with the date and time.
How do I format the where clause so that the time is taken off? I am still a newbie with oracle and what I have is this:
Select Distinct Table1.*, Table2.* from Table1, Table2 where Table1.file_name = Table2.file_name and Table1.downloaded_date = Table2.date_loaded and downloaded_date = '23/May/2008'
Of course, it's the last line not working because I don't know how to format it and no rows are retrieved when there are definately May 23rd rows stored in there.
The below sql is giving different number of result sets while adding further columns in select clause.i.e After adding the columns 4,5,6 in the below query its giving different number of result set.In this case the result set count would be 5.
Before adding the columns 4,5,6,the result set count was 11.
I have the following Union All query. It throws the following error in SQL plus
ERROR at line 27: ORA-01789: query block has incorrect number of result columns
After doing some google for the above error it suggests there are incorrect number of columns in the Union All query.I could not figure out the exact location well SQl Plus says error is on line 27 at the first opening bracket like
how can I select whole table in parts of 100 rows?
If I have primary key I can:
CODEstart=0; end=100; select * from table where ID>=start_point and ID<end; start=end; end=end+100; and repeat: CODEselect * from table where ID>=start_point and ID<end;
How can I do it without primary key? Is there another posibility to getting 100 number of rows? Maybe using rowid?
