Oracle trigger where clause updating
They can be used in exception handling to report, or, store in an error log table, the error that occurred in the code. Another possible method is to just use the SHOW ERROR command, but this only shows errors. Once the trace file is generated you run the tkprof tool against the trace file and then look at the output from the tkprof tool. The major sort are parameter is the SORT_AREA_SIZe parameter. You can increase copy latches via the initialization parameter LOG_SIMULTANEOUS_COPIES to twice the number of CPUs on your system. Where can you get a list of all initialization parameters for your instance? This is bad since it makes tracking which table the constraint belongs to or what the constraint does harder. What happens if a tablespace clause is left off of a primary key constraint clause This results in the index that is automatically generated being placed in then users default tablespace. This can be prevented or mitigated by breaking the transaction into a set of smaller transactions or increasing the size of the rollback segments and their extents. How can you tell if a database object is invalid By checking the status column of the DBA_, ALL_ or USER_OBJECTS views, depending upon whether you own or only have permission on the view or are using a DBA account. A user is getting an ORA-00942 error yet you know you have granted them permission on the table, what else should you check You need to check that the user has specified the full name of the object (select empid from scott.emp; instead of select empid from emp;) or has a synonym that balls to the object (create synonym emp for scott.emp;) 14.
These are especially useful for the WHEN OTHERS exception. How can you find within a PL/SQL block, if a cursor is open? The DBMS_OUTPUT package can be used to show intermediate results from loops and the status of variables as the procedure is executed. This can also be used to generate explain plan output. When looking at v$sysstat you see that sorts (disk) is high. How about an indication if they are default settings or have been changed You can look in the file for an indication of manually set parameters. Since this will usually be the same tablespace as the table is being created in, this can cause serious performance problems. What is the proper method for disabling and re-enabling a primary key constraint You use the ALTER TABLE command for both. A developer is trying to create a view and the database won? He has the "DEVELOPER" role which has the "CREATE VIEW" system privilege and SELECT grants on the tables he is using, what is the problem You need to verify the developer has direct grants on all tables used in the view. t create a stored object with grants given through views. If you have an example table, what is the best way to get sizing data for the production table implementation The best way is to analyze the table and then use the data provided in the DBA_TABLES view to get the average row length and other pertinent data for the calculation.
What is the difference between instantaneous and cumulative hit ratio and which should be used for tuning The hit ratio is a measure of how many times the database was able to read a value from the buffers verses how many times it had to re-read a data value from the disks. If it is not specified the tables that already exist will be skipped. You have a rollback segment in a version 7.2 database that has expanded beyond optimal, how can it be restored to optimal Use the ALTER TABLESPACE ..... This is bad because it causes user objects and temporary segments to be placed into the SYSTEM tablespace resulting in fragmentation and improper table placement (only data dictionary objects and the system rollback segment should be in SYSTEM). What are some of the Oracle provided packages that DBAs should be aware of Oracle provides a number of packages in the form of the DBMS_ packages owned by the SYS user. s default tablespace and all sizing information is lost. t store this information as a part of the constraint definition, but only as part of the index definition, when the constraint was disabled the index was dropped and the information is gone. (On UNIX) When should more than one DB writer process be used? How can you find their operating system id There are several ways.The benefit of taking a hot backup is that the database is still available for use while the backup is occurring and you can recover the database to any point in time.The benefit of taking a cold backup is that it is typically easier to administer the backup and recovery process.In addition, since you are taking cold backups the database does not require being in archive log mode and thus there will be a slight performance gain as the database is not cutting archive logs to disk.A data block is the smallest unit of logical storage for a database object.