Author Archives: james huang

Drop a Tablespace With a Datafile Missing

shutdown database. startup database in mount status. alter database datafile ‘PATH/filename’ offline drop. open database. drop tablespace tablespace_name including contents. Note, the below errors could be seen in alert.log: ORA-01135: file 4 accessed for DML/query is offline ORA-01110: data file … Continue reading

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Reconfigure OS Parameters After Linux Server Memory Upgrade

One of the Oracle database server ‘s memory is to be upgraded from 48GB to 72GB, so some parameters should be adjusted to take advantage of the newly added memory. 1)  Change ‘memlock’ parameter in /etc/security/limits.conf to 70G, which is … Continue reading

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“Database option mismatch: PDB installed version NULL.” in PDB_PLUG_IN_VIOLATIONS

There are below warning messages in PDB_PLUG_IN_VIOLATIONS : SQL>select NAME,CAUSE,MESSAGE,TYPE,CON_ID from PDB_PLUG_IN_VIOLATIONS; NAME CAUSE MESSAGE TYPE CON_ID ———— ———- —————————————————————————————————- ——— ———- RACTESTPDB OPTION Database option DV mismatch: PDB installed version NULL. CDB installed version 12.2.0.1.0. WARNING 3 RACTESTPDB OPTION … Continue reading

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How to Configure SHMMAX SHMMNI SHMALL ?

Every DBA is so familiar with those three kernel parameters in Linux — SHMMAX, SHMMNI and SHMALL. Most of the time, the default values are used by majority clients. But sometime, those three parameters need to be reconfigured to reflect the … Continue reading

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ORA-27154: post/wait create failed ORA-27300: OS system dependent operation:semget failed with status: 28 ORA-27301: OS failure message: No space left on device ORA-27302: failure occurred at: sskgpcreates

Below errors occurred while starting up a 12.2.0.1 Oracle database instance. SQL> startup ORA-27154: post/wait create failed ORA-27300: OS system dependent operation:semget failed with status: 28 ORA-27301: OS failure message: No space left on device ORA-27302: failure occurred at: sskgpcreates … Continue reading

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PARALLEL_MIN_SERVERS Parameter Behaviours In 12.2.0.1

By Default, when 12.2.0.1 instance starts up, there are more than necessary parallel processes created. In this test case, there are 133 parallel processes created when instance starts up. SQL>select * from v$px_process_sysstat where statistic like ‘%Server%’ STATISTIC VALUE CON_ID … Continue reading

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Create a Container Database (CDB) With A Subset Of Options Using DBCA In 12.2.0.1

For 12.1.0.2,  How to Create a Container Database (CDB) With Selected Options  For 12.2.0.1, we don’t need create scripts from DBCA first, manually modify scripts, then run the scripts sequentially to create a CDB/PDB database with required options in both … Continue reading

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PDB_PLUG_IN_VIOLATIONS

PDB_PLUG_IN_VIOLATIONS displays information about incompatibilities between a PDB and the CDB to which it belongs. SQL> select name,cause,type,action from pdb_plug_in_violations where status <> ‘RESOLVED’; NAME CAUSE TYPE ————- —————- ——— ACTION ——————————————- PDB$SEED SQL Patch ERROR Call datapatch to install … Continue reading

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RMAN-06004: ORACLE error from recovery catalog database: ORA-01422: exact fetch returns more than requested number of rows

SYMPTOMS Target Database : 12.2.0.1 RMAN Catalog  :  12.1.0.2 Trying to “upgrade catalog” from 12.2.0.1 RMAN and 12.1.0.2  RMAN catalog, then got below errors: connected to target database: RACTEST (DBID=2073981615) connected to recovery catalog database PL/SQL package RMAN.DBMS_RCVCAT version 12.01.00.02. … Continue reading

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How to Copy ASM Password File From Primary to Standby in 12cR1

12.1.0.2 primary database password file is stored in ASM, so it needs to be manually copied onto standby database ASM for dataguard configuration. Otherwise the below errors will occur: *** 2017-09-06 14:34:29.216 OCISessionBegin failed. Error -1 .. Detailed OCI error … Continue reading

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