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?
I am trying to design a database consolidation high-availability cluster for Oracle 11g R2 64-bit Enterprise Edition (X86-64) on Oracle Linux 6.x UEK, using Oracle 11.2.0.3 (the latest as of Aug 2012).
We don't need RAC Multi-Node now or in foreseeable future because none of the databases we run break the capacity of a single node. Likewise, we don't need to use Oracle VM to virtualise the database instances.
We plan to use SGA and PGA memory management to run multiple instances on same hardware operating on a single Linux 64-bit O/S image.Does it sound ok so far?
Two or three of 4-socket, 40-core Intel 64-bit servers with 512GB of RAM each (relatively cheap at today's HW commodity prices) will be sufficient to run all Oracle databases we have on Linux 64-bit.So the two HA options that I know of are:
(1) use Oracle Clusterware/Grid/ASM to provide for instance failover (2) use Oracle RAC One Node on top of Clusterware/Grid/ASM
As I understand it RAC One Node is significantly more expensive than the "free" Oracle Clusterware/ASM/Grid (since we own Oracle 11.2.0.3 Enterprise Licences already). So why should my employer pay for RAC One Node licence given they already own Single Instance Fail-Over and Restart protection from Clusterware/Grid/ASM ?
I also read that Data Guard 11.2 may not be supported with RAC One Node on 11.2? True? Will same Data Guard 11.2 work with a Single-Instance Failover running on Clusterware/Grid/ASM ?
-Who is running RAC One Node? Why? -Who is running Single Instance Failover with Clusterware? Why? -Who is using Data Guard with either of the above?
I have 11gR2 GI installed on two nodes. I am trying to convert a 10g single instance (uses ASM) database to RAC and getting this error. I am trying using 12c as well as manually by using rconfig.
[main] [21:19:15:145] [ASMInstance.initialize:135] First record =[Ljava.lang.String;@958bb8 java.lang.NullPointerException at oracle.sysman.assistants.rconfig.engine.ASMInstance.initialize(ASMInstance.java:153) at oracle.sysman.assistants.rconfig.engine.Step.execute(Step.java:283)
I 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.
I 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.
At 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.
While 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),
Can I add range sub partition to a hash partition table. Example like this.
CREATE TABLE test ( test_id VARCHAR2(10 ) , test_TYPE VARCHAR2(5) , CREATE_DATE date ) partition by hash (test_id, test_type) Partitions 3 SUBPARTITION BY RANGE (CREATE_DATE);
When Tried, I am getting syntax error as invalid option.
If 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.
I 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.
I 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:
A 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.
I 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 ?
Though the count in the Table after load is the same as the input file, they are all NULL.
I tried adding FIELDS TERMINATED BY X'A' for new line and also FIELDS TERMINATED BY X'D' for carriage return. Both times bad file was created and the records that were loaded were again NULL.
The input file has a list of emails: iatraveler2008@aol.com iaz65@aol.com 2blue2brown@comcast.net 2c3mwilson@embarqmail.com abigailolschan@comcast.net imisskoco@aol.com
I tried FIELDS TERMINATED BY X'10' and FIELDS TERMINATED BY X'13' too for new line and carriage return respectively. This time there were no bad file created, but the Table has Null values.
Log File contents:
Number to load: ALL Number to skip: 0 Errors allowed: 10000 Bind array: 64 rows, maximum of 256000 bytes Continuation: none specified Path used: Conventional Silent options: FEEDBACK, ERRORS and DISCARDS
I have one table called posh, which has about 50,000 ids (millions of rows) so far. It is currently at about 50 gb. So each series of rows for a particular id is about 1 mb.
CREATE CLUSTER posh_cluster (id int) SIZE 2M STORAGE (initial 2000K next 2000K) PARALLEL 4; CREATE INDEX posh_cluster_index ON CLUSTER posh_cluster;
[code].......
According to the Oracle documentation size is "the average cluster key size", I am not really sure what that means. Is this the 1mb in posh table space I am using for each series of rows for an id, or the space used for the index? Secondly, the storage parameter for 'CREATE CLUSTER' should be what?
How can i copy a single column from one table to another. Table 1 has a column with data in it, table 2 has the column but is empty, i want to copy data for a single column from table1 to table 2. By the way these table have multiple columns.
I am running 3 for loops in continuation. These loops retrieve me 63 values. I need to insert 1 single row in a table and then exit from the same. Moreover when i run the same loop again I need to insert 2nd value fo the second row in the table. The table is having a unique key which does not allow me to load redundant data.
i have to update a single column(x.c) in x table.here the condition is x.a is not null and x.b is not null x.d is null then update x.c=x.b for each row.
CREATE TABLE TEST11(TNO NUMBER(5), TVAL VARCHAR2(100), TID VARCHAR2(10)); INSERT INTO TEST11 VALUES(1,'VIJAYA','TEST'); INSERT INTO TEST11 VALUES(2,'VIJAYA','TEST'); INSERT INTO TEST11 VALUES(3,'VIJAYA','TEST'); INSERT INTO TEST11 VALUES(4,'VIJAYA',''); INSERT INTO TEST11 VALUES(5,'VIJAYA','');
[Code]....
My requiremen is if record is exists then i wan to update some value, if record not existes the i wan to insert new record
