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Simple .NET/ASP.NET PDF document editor web control SDKThe FLASHBACK_TRANSACTION_QUERY view lets you identify which transaction or transactions were responsible for a certain change in a table s data during a specified interval. A Flashback Transaction Query is simply a query on the FLASHBACK_TRANSACTION_QUERY view, and it can provide transaction information, including the SQL statements needed to undo all the changes made by either a single transaction, or a set of transactions during a specified interval of time. This feature enables you not only to correct logical errors, but also to conduct transaction audits in your database. Flashback Transaction Query gets all its transaction information from the undo segments. Thus, the value of your UNDO_RETENTION parameter detemines how far back you can go to retrieve undo data. When you use Oracle s LogMiner tool to undo SQL statements, Oracle has to serially read entire redo log files to get the necessary information. The Flashback Transaction Query feature lets you use an indexed access path to get to the required undo data directly, instead of traversing an entire redo log file. You can also undo a single transaction or a set of bad transactions during an interval of time. barcode activex control for excel 2007, barcode excel 2003 free download, excel barcode generator open source, barcode font for excel 2010, barcode in excel 2007 free, barcode macro excel free, barcode excel 2007 freeware, free barcode add-in excel 2007, excel 2010 barcode generator, barcode font for excel 2010 free,Source code compiled to managed code can use all native types as well as all managed types, just as C++ code can use C structs, enums, and unions, as well as C++ classes To say this in other words, the C++ type system is the lowest common denominator between sources compiled to native code and sources compiled to managed code This means that you have to restrict yourself to the C++ type system if you define methods that act as migration boundaries all managed functions that should be callable from native code and all native functions that should be callable from managed code can use only native types However, any kind of native type can be used in the method signature You can use native classes, structs, unions, enums, pointers of any level of indirection, references, and const variants of all native types. You need the SELECT ANY TRANSACTION system privilege to query the FLASHBACK_TRANSACTION_QUERY view. This view contains columns that let you identify a transaction s time stamp, the identity of the user who made the transaction, the type of operations done during the transaction, and the undo statements necessary to retrieve the original row. Listing 6-2 shows the structure of the FLASHBACK_TRANSACTION_QUERY view: Listing 6-2. The Flashback Transaction Query View SQL> DESC flashback_transaction_query Name Null Type ------------------------------------------------XID RAW(8) START_SCN NUMBER START_TIMESTAMP DATE COMMIT_SCN NUMBER COMMIT_TIMESTAMP DATE LOGON_USER VARCHAR2(30) UNDO_CHANGE# NUMBER OPERATION VARCHAR2(32) TABLE_NAME VARCHAR2(256) TABLE_OWNER VARCHAR2(32) ROW_ID VARCHAR2(19) UNDO_SQL VARCHAR2(4000) SQL> The FLASHBACK_TRANSACTION_QUERY view contains the following columns: START_SCN and START_TIMESTAMP identify when a certain row was created. COMMIT_SCN and COMMIT_TIMESTAMP tell you when a transaction was committed. XID, ROW_ID, and UNDO_CHANGE# identify the transaction, the row, and the undo change number, respectively. OPERATION tells you whether the DML operation was an insert, update, or delete operation. Now we send an e-mail notification to the account stating that it has been locked. Once again, if the debug e-mail is set, the message will go to that address and not to the real user. If you see a value of UNKNOWN under the OPERATION column, it means that there isn t sufficient undo information in your undo tablespace to correctly identify the transaction s exact operation type. LOGON_USER, TABLE_NAME, and TABLE_OWNER provide the username, table name, and schema name. UNDO_SQL gives you the exact SQL statement required to undo the transaction. Here s an example of the type of data you would find under the UNDO_SQL column: delete from "APPOWNER"."PERSONS" where ROWID = 'AAAP84AAGAAAAA1AAB';
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