Hash Value Generation
Aug 21, 2012I have a question.
When and Where HASH VALUE for a given SQL statement get generated?
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SQL & PL/SQL :: How Hash Is Computed
May 22, 2013Is it true that the SQL hash is computed on the SQL text only ?
View 4 Replies View RelatedSQL & PL/SQL :: What Is Hash Join
Jul 12, 2012what is Hash join?how it is different from inner join?what is the sign used for inner join?(eg: like the (+) sign used for outer join)?
View 1 Replies View RelatedPL/SQL :: How To Use Hash Join
Jan 13, 2013If i have a table T1 and a table T2. Table T1 is having 100 rows and table T2 is having 20 rows. When performing a Hash join ,which table should be used to make the hash table ,the larger one or the smaller one and why ?IF the data set is too small for considerations then please conser table T1 with 10 million of rows and table T2 with 1 million of rows.
View 11 Replies View RelatedPerformance Tuning :: Different SQL ID For Same HASH-VALUE?
Nov 2, 2012I see one of my SQL's which is ran by the user on a 10.2.0.3 database changing its SQL_ID after some runs even if the query is not changed a bit! However the HASH VALUE for this query remains the same.
how a same query can have different SQL_ID's but same HASH_VALUE?
Note: Statistics are not modified on the base tables of this query.
SQL & PL/SQL :: Hash Partition Table
Jun 27, 2010I am facing a problem in fetching / updating records from a customer details table having around 20 million records. The table contains around 30 fields with 'MOBILE_NO' as primary key. most of the queries are having 'mobile_no' in where clause .I am planning to hash partition that table using mobile_no column as there is no other column available which can be used for partition.
clarify whether creating hash partition on such key would increase performance of data extraction as I have read on net that hash partitioning is not effective for performance tuning.
Hash Group By Improvement?
Aug 7, 2013I see that one of my queries from an application time is spending most of its time in the hash group by. I'm running Oracle 11g with a quarter rack exadata appliance. Is there a better way to run or design this table? query:
SELECT COUNT(*)
FROM (
SELECT "DDTMDAY", "MRKTNM", "BSMNM", "BSCNM", "CLNM", "CSCDNM", "BTSID", "SECTSEQID", "BNDID", "FAID", SUM("VATTCNT"), SUM("VMBLORGCNT"), SUM("VMBLTERCNT"), SUM("VSILENTRETRYCNT"), SUM("VCUSTBLKCNT"), SUM("VAXSFCNT"), SUM("VCEBLKCNT"), SUM("VWCDBLKCNT"), SUM("VT1BHLBLKCNT"), SUM("VPWRBLKCNT"), SUM("VNONBTSEQBLKCNT"), SUM("VSFULCALLCNT"), SUM("VDRPCALLCNT"),
[code]...
Combining Hash Cluster And Indexes
Oct 28, 2010A basic select and group by query I am optimising for my Database course has returned results that indicate it will perform better on a clustered index when returning a smaller number of rows (5% of the largest table) and on a hash clustered index when returning higher volumes (50% and 80%). I understand that it is possible to use more than one index type on a table to improve performance, but I am struggling to understand how I might establish a hash cluster and a cluster on the same table? and then use hints to drive the query down one access path or the other.
Site admin - this site is a very useful resource.
SQL & PL/SQL :: Hash Join And Nested Loops
Mar 16, 2011What is the difference between Hash join and Nested Loops in pl / sql?
View 1 Replies View RelatedSQL & PL/SQL :: What Is Hash Join And Sort Merge
Jun 12, 2012I tried to search on google for "Hash Join" And "Sort Merge". But unfortunatly i am unable to understand that articles. "Hash join" And "Sort Merge".
View 3 Replies View RelatedSingle Table Hash Clusters
Mar 16, 2013I created a single table hash cluster like this :
create tablespace mssm datafile 'c:appmssm01.dbf' size 100m
segment space management manual;
create cluster hash_cluster_4k
( id number(2) )
size 8192 single table hash is id hashkeys 4 tablespace mssm;
-- Created a table in cluster with row size such that only one record fits one block and inserted 5 records each with a distinct key value
CREATE TABLE hash_cluster_tab_8k
( id number(2) ,
txt1 char(2000),
txt2 char(2000),
txt3 char(2000)
)
CLUSTER hash_cluster_8k( id );
[code]....
If I issue the same query after creating unique index on hash_cluster_tab(id), the execution plan shows hash access and single I/O (cr = 1).Does it mean that to have single I/o in a single table hash cluster, we have to create unique index? Won't it create additional overhead of maintaining an index?
What is the second I/O needed for in case unique index is absent?
Hash Partition On Primary Key Columns?
Jul 18, 2012I have a existing non partition table with more than 100 million records,planning to re design using Hash partition.This table doesn't has any range column to do range partitioning.
Table has 40 columns with a Primary Key on two columns (guest_sales_Id ,Version Flag). guest_sales_Id is unique for entire table but with anopther column version Flag declared as Primary key.(Version Falg will have only two distinct values in entire table)
If i do hash partition,do i need to declare on two columns which are declared ad Primary key ?If i use only guest_sales_id to declare hash prtition any issues ?
SQL & PL/SQL :: Hash Partition On Fact Table
Sep 27, 2010I created the 32 hash partition on a fact table. Based on hash parititon technique it should evenly distribute data accross the different partition.But when i analyze the table and check the distribution its not at all even.
P_Name Tabspace num_Rows
SYS_P21TBS_TBS0
SYS_P22TBS_TBS0
SYS_P23TBS_TBS0
[Code]....
Security :: How To Decrypt DBMS_CRYPTO.HASH Encrypted Value
Mar 27, 2013note we need to decrypt the data which is encrypted using dbms_crypto.hash algorithm. it is possible to decrypt dbms_crypt.hash
eg
SQL> select DBMS_CRYPTO.hash(utl_raw.cast_to_raw('Foo'), 3) FROM dual;
DBMS_CRYPTO.HASH(UTL_RAW.CAST_TO_RAW('FOO'),3)
--------------------------------------------------------------------------------
201A6B3053CC1422D2C3670B62616221D2290929
Performance Tuning :: Find SQL Using Hash Value - ORA-00060
Nov 18, 2010Getting an ORA-00060 in our database. This is the alert log:
Wed Nov 10 08:01:54 2010
Global Enqueue Services Deadlock detected. More info in file
/opt/oracle/admin/ngboot/bdump/ngboot1_lmd0_13119.trc.
This is part of the lmd file:
oprocp : (nil)
opid : 0
group lock owner : (nil)
xid : 0000-0000-00000000
dd_time : 0.0 secs
dd_count : 0
timeout : 0.0 secs
[Code] ......
How do I find the SQL causing this? I have the hash value of 3180952482. should I open up en SR as this i logged in an lmd trace?
SQL & PL/SQL :: DBMS_CRYPTO Hash A BLOB In A Union Over Dblink?
Dec 27, 2012With this table in local and remote database via a DBLink
CREATE TABLE PICTURES (
ID NUMBER(12),
PICNAME VARCHAR2(20),
PICTURE BLOB
);
How come I can get the hash of the picture column fine like this:
SELECT dbms_crypto.hash@dbLink(PICTURE, 3)from SCHEMA1.PICTURES@dbLink;
but I can't do it in a union with the local database?
SELECT dbms_crypto.hash@dbLink(PICTURE, 3)from SCHEMA1.PICTURES@dbLink
UNION
SELECT dbms_crypto.hash(PICTURE, 3)FROM SCHEMA1.PICTURES;
gives "ORA-06553: PLS-564: lob arguments are not permitted in calls to remote server"
SQL & PL/SQL :: Column To Row Generation
Jul 18, 2013Here i've a case of, For single test there are multiple chemist's assigned to it. I want a result for each chemist assigned how many test.
I want the output like below.
CREATE TABLE SAM.TEMP
(
ID NUMBER(4),
CHEMIST_ID VARCHAR2(30)
)
/
[Code]....
Server Administration :: How To Calculate Number Of Hash Keys
Mar 31, 2011I was reading the documentation for oracle 11gr2, with reference to URL>.....
The following examples show how to correctly choose the cluster key and set the HASH IS, SIZE, and HASHKEYS parameters. For all examples, assume that the data block size is 2K and that on average, 1950 bytes of each block is available data space (block size minus overhead).Note that 34 hash keys are assigned for each data block
how they arrive at 34 hash keys because another portion of the document states
This space determines the maximum number of cluster or hash values stored in a data block. If SIZE is not a divisor of the data block size, then Oracle Database uses the next largest divisor.
if that is the case, then number of hash keys should be 1900/55 = 34.55 which should have rounded up to 35.
Use Range-hash Partitioning Of A Large Dimension Table
Apr 12, 2013At moment we use range-hash partitioning of a large dimension table (dimension model warehouse) table with 2 levels - range partitioned on columns only available at bottom level of hierarchy - date and issue_id.
Result is a partition with null value - assume would get a null partition in large fact table if was partitioned with reference to the large dimension.Large fact table similarly partitioned date range-hash local bitmap indexes
Suggested to use would get automatic partition-wise joins if used reference partitioningWould have thought would get that with range-hash on both dimension.
SQL & PL/SQL :: Auto Generation Of Number
Feb 27, 2013Need to generate auto number as below
A00001 to A99999. After A99999 it should begin with B00001 and ends with B99999. till Z99999 we need to generate.
SQL & PL/SQL :: Letter Generation In Word?
Jul 2, 2012i need to write to word doc from pl/sql . these are letters which needs to printed . Can i use the same UTL_FILE and will i be able to control the font etc from pl/sql
View 6 Replies View RelatedSQL & PL/SQL :: Sequence Number Generation
Jul 26, 2010I am using following Procedure/function for inserting DATA into New table:
PROCEDURE NEMPID IS
OFFICER CHAR(1) := '0';
OFFICIAL CHAR(1) := '9';
CURSOR DOJSUP IS
[Code]....
Get/Retrieved data from personal and cat9 files and Inserted Data stored in file NEMP as
EMP_ID NEMP_ID
------- ---------
111 01-8722
132 01-9224
88 01-8318
114 01-8717
106 01-8517
[Code]....
I want also generate a sequence/serial number for same category/designation of personals/employees exist in personal file ?
Like 001, 002 ,003 at the end of NEMPID field.
EMP_ID NEMP_ID
------- ---------
111 01-8722-001
132 01-9224-002
88 01-8318-003
114 01-8717-004
[Code]....
HOW CAN GENERATE SEQUENCE/SERIAL NUMBER OF SAME CATEGORY EMPLOYEES AND INSERT INTO TABLE NEMP?
PL/SQL :: File Number Generation
May 15, 2013Here is my situation.
1. I generate file_name through a function.
2. File name like File_DD_MM_YY_FLXXX.
3. Now this FLXXX is the filenumber. It will be 1 for the 1st run of the day and for each of the new run it will be +1. Again next day it will start from 1.
So right now I am using a sequence and resetting it at 12 AM to 0. Is it a good approach to solve the scenario?
Too Much Archivelog Generation In 11gr2?
Sep 25, 201311gr2, HP-UX, 64-bit. From last one week, we are seeing tremendous increase in archive-log growth. Its comes almost around 110GB per a day (db size=600g). I don't think its usual.Alertlog is clean and we don't see any alerts. Remedy app is built on this db and its creating tables on fly with LOB columns and indexes on them. As a first step. shall I disable logging for indexes on LOB columns ?
View 4 Replies View RelatedPerformance Tuning :: Create Hash Partition On Fact Tables?
Aug 5, 2010I have to create a hash partition on fact tables.. we can use temp tablespace or permanent tablespace.
View 10 Replies View RelatedServer Administration :: Partition Exchange In Hash Partitioned Table
Mar 13, 2012While trying partition exchange feature of Oracle with 2 hash partitioned tables, I come to know that I can't directly exchange partitions between 2 partitioned tables
I have two hash partitioned tables , so to move partition data from one table to another will include-
1) Exchange from partitioned table to non-partitioned table.
2) exchange from non-partitioned table to new partitioned table.
But I am not sure in which hash partition my data will go in new partitioned table (data need to be moved has single key value on basis of which tables are partitioned),
Character Report Generation Too Slow
Oct 12, 2010I am using :
Database : Oracle 8i
Application Server: Oracle AS 9i
Developer Suite : Oracle 6i(forms & reports)
I have created some character reports in oracle reports 6i.. when reports used run from my ERP(oracle 6i oriented) ... report usually took time to create on server. Sometimes my ERP used to hang up due to busy reports generation. And then we have to kill some processes to finally create charater reports on emergency basis.What is the valid reason for slow generation of report(character file )?
Server Administration :: Too Many Archive Log Generation?
Mar 16, 2012on weekends we have too many archive logs generated .i have taken the data of a week and found that average archive log generated from monday to friday is 7 files per day but on satuarday and sunday the average is 60 files and FG1 gets full. on weekends we have all type of backups running like incremental,archival and logical backups and on sunday we have full physical backup
what is the reason of too many archive log files generations at weekends. is it due to hot and logical backups , if yes then how ?
Forms :: Invoice Number Generation?
Aug 24, 2011i an using this code to generate invoice numbers auntomatically:
declare
po number;
pi number;
begin
[code]...
Problem is it does not increment after 10.
Forms :: Barcode Generation And Printing
Dec 14, 2011We need to generate barcode through oracle forms and print the barcode using Zebra Printer.
How to generate the barcode using oracle forms and which software we should use to generate the barcode as well as how can we print the barcode label with customize information on label with barcode.