Determine the replication agents’ status
Insight on replication agent status can be collected manually or programmatically. This article will consider both cases, and also when a replication agents’ status will be determined in relation with all publications, or a particular one.
February 24, 2017
Database status overview
Every database in a SQL Server environment has two basic states: full availability (online state) or full unavailability (offline state).
February 20, 2017
Failover event overview
In general, the term “failover” refers to switching from a previously active machine, other hardware component, or network to a passive (or unused) one, to sustain high availability and reliability. In most cases, a failover event is an automatic process, while a the similar event, switchover, requires manual intervention in switching between the active/passive elements.
January 13, 2017
SQL Server availability overview
The core component of SQL Server is the Database Engine service. It is identified with the Windows service named MSSQLSERVER (sqlservr.exe) for the default instance, and for the named instance, the customized instance name is appended to the name of the service, e.g. MSSQLTESTDEPT.
January 5, 2017
System availability overview
Overall stability and availability of a particular machine in a specific time range is usually called system uptime. This measurement represents a period (sometimes percentage) when the system is stable and performing without unattended reboots, except for maintenance and administrative purposes, and works without issues. The opposite, system downtime is a period when machine is turned off (on purpose), or encounters experiences problems that result is the system being unavailable to users and processes. The combination of these two measurements is called system availability which is both identified and tracked with Windows Event Viewer (System Log).
December 23, 2016
Wait statistics = Data
SQL Server’s built in abilities to track query execution via wait statistics is critical to resolving performance problems. Wait statistics or response time analysis are metrics that provide the ability to measure the time needed for the database to respond to executed queries. It doesn’t simply represent the time needed for a query to complete execution, but the wait statistic is also the measurement of the time the query has taken for each step in its execution. That information becomes the basis for identifying bottlenecks that are affecting the execution time.
December 20, 2016
Blocked processes caused by locks on database objects are a common issue. Locking ensures the integrity of data stored within databases by forcing each executed SQL Server transaction to pass the ACID test. which considers that every transaction must meet the following requirements:
December 12, 2016
SQL Server Agent overview
The main purpose of SQL Server Agent is executing administrative tasks within SQL Server, mostly as on-demand user actions. It is Windows service which runs continuously in the background, but it stores necessary information within SQL Server itself, in the msdb system database.
December 6, 2016
Performance troubleshooting strategy
The following recommendations are part of an effective strategy for investigating SQL Server performance issues caused by slow queries:
November 23, 2016
Part 1 of this series describes some basics about performance baselining, while Part 2 explains how to establish and use baselining for detecting SQL Server performance issues in SQL Server using user defined tables, scripts and baseline calculations. In this final article, we’ll demonstrate how to implement baselining with a 3rd party tool, including some value added functionality
October 26, 2016