utm checkpoint

files, LGWR will not write different groups of log files at the same time.In different cases, when the redo log is invalid, the LGWR lock uses the following actions:1) LGWR can write at least one member file in the group: The write operation is completed normally. LGWR writes accessible member files to the group and ignores inaccessible member files.2) during log switching, LGWR cannot access the next group because the group needs to be archived: temporarily stop the database operation and wait

1. How to generate or modify SQL statementsUse Insert-> checkpoint-databasecheckpoint to generate a database checkpoint. During the generation process, you must set a query statement and obtain a query result table based on the query statement, the data in this table is the expected data. In the future, when running the script, qtp obtains actual data from the current database based on the query statement,

1.1.Log CheckpointInnoDB transaction log refers to Redolog, which is called log , stored in the log file ib_logfile* inside. InnoDB There is another log of undo logs, but the undo log is stored in the shared tablespace (ibdata* file).Because Log and Checkpoint are closely related, these two parts are analyzed together.Noun Explanation:LSN, log sequence number,Innodb 's log sequence number is a full-bit integer.1.1.1.Write mechanism1.1.1.1.Log Write

its multivariate copy. Each redo log group is defined by a number, such as Group 1, group 2, and so on. Each log file must be active so that LGWR can write both log files at the same time LGWR does not write to different groups of log files at the same time.In different cases, when the redo log is invalid, the LGWR lock takes the following actions:1) LGWR can write to at least one member file in the group: The write operation is completed normally. LGWR writes an accessible member file in the g

db_name(database_id)5 ORDER by Count(page_id)DESCDatabase Dirty PagesPeople 2524Tempdb 61Master 1As indicated above, there are 20M dirty pages in the People database (2524 * 8/1024).These dirty pages (Dirty page) are periodically written back to the database whenever there is insufficient cache idle or checkpoint (checkpoint). For faster allocation of pages, SQL Server always keeps a certain number of ava

What checkpoint does: refresh the dirty pages in the buffer pool back to the disk. The difference is that the number of dirty pages Retrieved each time to the disk, and when to trigger the checkpoint. Checkpoint: 1. shorten the database recovery time (what checkpoint does when the database goes down: refresh the dirty

Author: runming QQ: 226399587 http://blog.csdn.net/runming918As an important mechanism in oracle, SCN (System Chang Number) plays an important role in Data recovery, Data Guard, Streams replication, and synchronization between RAC nodes. Understanding the operating mechanism of SCN can help you gain a deeper understanding of the above functions.Before understanding SCN, Let's first look at how data changes in oracle transactions write data files:1. Start the transaction;2. Find the required data

according to the table:Initial time Load phase: During the initial data load phase, the extract process extracts data directly from the data table on the source side.Synchronization change capture phase: After initial data synchronization is complete, the extract process is responsible for capturing the source-side data changes (DML and DDL)Goldengate does not support DDL operations on all databasesThe extract process captures all configured object changes that need to be synchronized, but only

as from different factions of the people fighting. From the product competition relationship, it is possible to collide with IPs is UTM (Unified threat management platform), because they are the same type of security products, and UTM contains more than IPs security features, IPS is only a subset of UTM, theoretically, UTM