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.NET/Java PDF, Tiff, Barcode SDK LibraryOracle immediately applies row-level locks, where needed, to prevent other processes from trying to change the same data simultaneously 8 The server writes the change vectors to the redo log buffer 9 The server modifies the table data (inserts the new row) in the data buffer cache 10 The user commits the transaction, making the insertion permanent Oracle releases the row locks after the commit is issued 11 The log writer process immediately writes out the changed data in the redo log buffers to the online redo log file.. how to make barcodes in excel 2010, microsoft excel 2013 barcode font, free3of9 barcode font excel, free barcode generator microsoft excel, open source barcode generator excel, how to create 2d barcode in excel, barcode activex in microsoft office excel 2010, barcode excel 2010 microsoft, barcode in excel formula, barcode generator excel 2010,12. The server process sends a message to the client process to indicate the successful completion of the INSERT operation. (If it couldn t complete the request successfully, it sends a message indicating the failure of the operation.) 13. Changes made to the table by the insertion may not be written to disk right away. The database writer process writes the changes in batches, so it may be some time before the inserted information is actually written permanently to the database files on disk. In the previous example, since a new row is being inserted, there is no undo information to record in the undo tablespace. If the user had updated a row instead, Oracle would have had to record the before-update row in the undo records. Until the original transaction commits the update, all other users will see the original data values of the row. You could improve the script s performance as follows, although it reduces readability. Instead of performing a date call to set each time and date variable, you could make one date call that outputs space-delimited values, then place those values into an array. To initialize the array in ksh, use Databases aren t very useful if a large number of users can t access and modify data simultaneously Data concurrency refers to the capability of the database to handle this concurrent use by many users To provide consistent results, the database also needs a mechanism within it that ensures users don t step on each other s changes Data consistency refers to the ability of a user to get a meaningful and consistent view of the data, including all the changes made to it by other users Oracle uses special structures called undo segments to ensure data consistency For example, when you re reading a set of data for a transaction, Oracle ensures that the data you read is transaction-set consistent; that is, it guarantees that the data you see reflects a single set of committed transactions. The first catch block in this code catches C++ exceptions of type int, and the second one catches any CTS-compliant managed exceptions. When a C++ exception of a type other than int is thrown, the CLR s exception mapping mechanism will detect this and map the exception to a managed exception. Since the SEH exception code of a C++ exception (0xE06d7363) is not handled specially, the runtime maps it to an SEHException. You should always catch C++ exceptions before you catch managed exceptions of type System::Object^, System::Exception^, System::SystemException^, System::Runtime::InteropServices::ExternalException^, and System::Runtime::InteropServices::SEHException^. The first four types mentioned are base classes of SEHException. If a C++ exception is thrown and a catch block for one of the exceptions mentioned here is found, the runtime will map the exception to an SEHException. In the following code, the exception handler for int would never be executed: int main() { try { f(); } catch (Exception^ ex) { Console::WriteLine(ex->GetType()->FullName); } catch (int i) { Console::WriteLine("int exception, value={0}", i); } }
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