.NET/ASP.NET/C#/VB.NET PDF Document SDK
The dynamic cast performs a runtime check and returns a nullptr if the type of the casted object does not support the target type Therefore, the preceding code checks if the cast is not nullptr to find out if the cast was successful In the sample code shown here, it is only required to find out if an expression can be casted and the result of a successful cast is not needed In contrast to other languages, C++/CLI does not support an extra construct for this need C#, as an example, has the is operator to find out if an expression is castable to a given type // this is C# code: if ( req is FtpWebrequest ) .. variable req can be casted to an FtpWebRequest .. Even though this C# expression appears to be more expensive than the equivalent C++/CLI expression, the same IL instructions are generated for both cases.barcode add in for excel 2010, excel ean barcode font, excel 2010 barcode generator, barcode fonts for excel 2010, barcode inventory excel program, microsoft excel 2013 barcode add in, how to make barcodes in excel free, excel barcodes not working, ms excel 2013 barcode font, how to make barcodes from a list of numbers in excel 2010,
The ALTER DISKGROUP command can be used to add a new disk, as shown here: SQL> ALTER DISKGROUP group1 ADD DISK '/devices/disk5' name disk5, '/devices/disk6' name disk6,
The ALTER DISKGROUP command can be used to drop a disk, as shown here: SQL> ALTER DISKGROUP group1 DROP DISK disk5; You can use the following command to remove a disk group, after putting the database in the MOUNT state: SQL> DROP DISKGROUP group1 INCLUDING CONTENTS The UNDROP clause keeps a pending DROP DISK command from happening. If the disk has already dropped, there is no way for you to retrieve it, even using UNDROP. The optional FORCE clause means you can t use the UNDROP clause and you can never UNDROP a whole disk group. Here s an example of the UNDROP clause: SQL> ALTER DISKGROUP group1 UNDROP DISKS; This cancels the pending drop of all disks from the group1 disk group.
When ASM rebalances a disk group, it does so automatically and dynamically. It does this whenever you change the status of a disk in a disk group, whether you are adding or removing a disk from the disk group it attempts to maintain an I/O balance across all the disks in a disk group. So, when you add or remove disks, you disturb the I/O balance, but ASM sets it right automatically by moving data appropriately for the space you added or removed.
rsync -av -e ssh user@remotehost:/src/dir/ /local/dest/dir/
Since there will be a performance hit on your system while ASM rebalances a disk group, you should consolidate the times when you add and remove disks so that you reduce the number of times that ASM has to rebalance.
You can also manually rebalance the disk groups if you wish, using the following command; you can assign a value of 1 through 11 for the POWER clause: SQL> ALTER DISKGROUP dgroup1 REBALANCE POWER 5; The POWER clause specifies how fast ASM performs the REBALANCE command. Setting the POWER clause high increases the speed of the rebalancing. The default is 1 (the default value for the ASM_POWER_LIMIT parameter). Specifying POWER means you are overriding the value you assigned to the ASM_POWER_LIMIT initialization parameter when you started the ASM instance. Of course, it would be nice to rebalance disks quickly rather than slowly, but due to the overhead involved, there s a tradeoff between rebalancing speed and database performance.
The data files you create in a regular database aren t like the ones in an ASM setup. ASM file management takes over your normal operating system files, which become ASM files and, when you create a new data file, control file, or redo log, you simply specify an ASM group and not an operating system file name. So, to create a new tablespace on an ASM disk group, you would run a command like the following: SQL> CREATE TABLESPACE tbsp1 DATAFILE '+group1';
The concrete WebRequest-derived classes do not support public constructors that could be used to create a new instance The only way to instantiate an HttpWebRequest for a URL is to call WebRequest::Create passing an HTTP- or HTTPS-based URL In addition to the members of WebRequest, HttpWebRequest offers many members that are specific for the HTTP protocol (eg, to specify whether a GET or a POST request should be made) To access these members, the WebResponse handle returned by WebRequest::Create must be downcasted to an HttpWebRequest handle There are different options to achieve such a downcast As in the sample before, a dynamic_cast could be used The dynamic_cast returns nullptr either if the input was a nullptr or if the cast was not successful.