sql server transaction log reader

exclusive (X) lock to update. A deadlock occurs because two transactions are converted to exclusive (X) locks, and each transaction waits for another transaction to release the shared-mode lock.To avoid this potential deadlock problem, use the update (U) lock. Only one transaction at a time can obtain an update (U) lock on the resource. If the

As we know, the SQL Server transaction log is used primarily to record changes made to the database by all transactions, and if the system fails, it becomes the only source of the latest data. Log operations often have the following applications: One, the

Tags: blank LLB article analysis current EXCE code word allowsTurn from: Nested transactions in SQL Server use--transaction count indicates a mismatch between the number of BEGIN and COMMIT statements--The underlying problemProblem:1. System.Data.SqlClient.SqlException (0x80131904): The transaction count after EXECUTE

.*/Cause of the problem:The "xact_abort" switch specifies whether SQL Server automatically rolls back to the current transaction when a run-time error occurs for the Transact-SQL statement. When SET Xact_abort is on, the entire transaction terminates and rolls back if the Tr

shows that one row no longer exists in the second read or subsequent read because the row has been deleted by other transactions. Similarly, due to the insert operation of other transactions, the second or subsequent read of the transaction shows that a row does not exist in the original read.The above four problems will cause data inconsistency. We setThe level at which the transaction is prepared to acce

13.2.3 Deployment Log Shipping Initial ConfigurationSome initial configuration is required before the log shipping is deployed. You need to configure shared folders for replication of transaction log backups and backups, set up an agent run account and the primary DB instance to run the account, and configure the accou

default log file storage location Which of the following folders stores the database files and log files when you create a new database: The default value is \ MSSQL \ Data in the installation directory of your SQL server.Of course, you can point to any other permitted path when you create a database.Method 1: (Create a database using the Enterprise Manager)Ent

: COMMIT Transaction3 Rolling back transactions: ROLLBACK TRANSACTIONTransaction classification:1 Explicit transactions: explicitly specify the beginning of a transaction with BEGIN transaction.2 Implicit transaction: Open implicit transaction: Set implicit_transactions on, when operating in implicit

isolation is to avoid these 3 situations.Dirty read: Read data that has been modified but not committed by other transactionsNon-REPEATABLE READ: Two queries in the same transaction read different dataPhantom read: Two queries in the same transaction read a different number of recordsSome people may not understand the definition of phantom and non-repeatable reading, the biggest difference is essentially t

include: Begin Tran commit Tran rollback Tran command Distributed transactionsTransactions that span multiple servers are called distributed transactions. SQL Server can be operated by DTC Microsoft Distributed Transaction Coordinator.To support distributed transactions. You can use the begin Distributed Transaction

SQL ServerAndOracleFeatures of medium Transaction Processing 1Transaction Features (AcidAttribute) NAtomicAtomicityThat is, the transaction should be taken as a unit of work, and the transaction is processed completely. All the work is either saved in the database or completely rolled back, but not retained.. NCon

Tags: transactional replication distribution Transactional replicationHow to handle large transaction operations in SQL Server transactional replicationWorking mechanism of transactional replicationTransactional replication is implemented by the SQL Server Snapshot Agent, th

SQL server lock mechanism (I)-Overview (lock types and ranges) SQL SERVER lock mechanism (II)-Overview (Lock compatibility and lockable resources) This article introduces the locking mechanism of SQL SERVER (iii) -- Overview (loc

After careful study, it is still a bit complicated to find the explicit transaction (display transaction) inside SQL Server. Here are some summaries:Commit TRANSACTION commits all nested transaction modifications. However, if the

The transaction is about atomicity. The concept of atomicity means that some things can be viewed as an inseparable unit. From a database point of view, it refers to the smallest combination of one or more statements that should be executed all or not at all.To understand the concept of a transaction, you need to be able to define very clear boundaries. The transaction