SEMMSL Set to 10 plus the largest initsid.ora PROCESSES parameter of an Oracle database on the system. The PROCESSES parameter can be found in each initsid.ora file, loc ORACLE_HOME/dbs directory. The default value of PROCESSES for the 8.1.5 prebuilt database is 50. SEMMNS Set to the sum of the PROCESSES parameter for each Oracle database…
The only drawback in setting the processes value high is that the corresponding kernel settings, SEMMNS and SEMMSL need to be set higher based on the following formulas: SEMMSL – Set to 10 plus the largest PROCESSES parameter of any Oracle database on the system. SEMMNS – Set to the sum of the PROCESSES parameter…
If you use dbms_stats in 10g it will not automatically invalidate dependant cursors. This is the default behaviour as of 10. To revert to older previous behaviour you will have to set the parameter no_invalidate to false. . no_invalidate Does not invalidate the dependent cursors if set to TRUE. The procedure invalidates the dependent cursors…
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Backing it up in a human readable format: alter database backup controlfile to trace; alter database backup controlfile to trace as ‘/some/arbitrary/path’; alter database backup controlfile to trace as ‘/some/arbitrary/path’ reuse; If you are using “alter database backup controlfile to trace as ‘test1.sql’; then test1.sql will be created in $ORACLE_HOME/dbs folder.
Here is a much simpler version: ——————————- Create table t1 (c1 number primary); session1: insert into t1 values (1); session2: insert into t1 values (1); — would hang v$lock would reveal session 1 blocking session2 on TX lock why? because you have a constraint where you are asking Oracle to check uniqueness of data (unique…
Case 1:- Allocate More space to temp tablespace before starting the analyze. U can reclaim space by doing. Alter tablespace temp offline; Alter tablespace temp online; Alter tablespace temp coaelsce; Case 2:- If there is some spcace then allocate around 10 GB of space to TEMP .
A new mechanism to control the allocation of temporary storage space was introduced in 7.3, initially as support for OPS, but it is equally applicable to non-OPS environments. This requires the creation of a designated temporary tablespace, that is one created with the designation TEMPORARY. The effect of this is twofold: 1. No permanent objects…
After doing further research on Oracle errors from metalink, I found following for ORA-8031. CAUSE: The data_object_id (seg/obj) stored in the block is different than the data_object_id stored in the segment header. EXPLAINATION: The expected behavior can be that tables are being truncated while a query from those tables is still in execution. Look if…
Read More “ORA-8031 issue and solution if it is occuring due to truncate.” »
Dropping a Database in 10G Consists of the following steps. echo $ORACLE_SID sqlplus “/as sysdba” SQL> startup nomount; ORACLE instance started. Total System Global Area 1077936128 bytes Fixed Size 2034344 bytes Variable Size 427824472 bytes Database Buffers 633339904 bytes Redo Buffers 14737408 bytes SQL> alter database mount exclusive; Database altered. SQL> alter system enable restricted…
declare cursor c1 is select distinct PRODUCT_SKU, FIT_ID from geo_florist order by PRODUCT_SKU, FIT_ID; begin for cur1 in c1 loop delete from geo_florist a where a.rowid != ( select max(b.rowid) from geo_florist b where a.product_sku = b.product_sku and a.fit_id = b.fit_id) and a.product_sku = cur1.product_sku and a.fit_id = cur1.fit_id; if (mod(c1%rowcount, 1000) = 0) then…
