SQL Outdated Statistics Test

In SQL Server, outdated statistics refer to statistical data about the distribution of values in a table or index that is no longer representative of the current data. These statistics are crucial for the query optimizer to make informed decisions about the most efficient way to execute a query.

Monitoring outdated statistics in SQL Server is essential for maintaining optimal query performance and system reliability. This test monitors outdated statistics in SQL Server and reports the metrics Outdated statistics by day and Outdated statistics by row modified.

Target of the test : A Microsoft SQL server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for the Microsoft SQL Server that is being monitored

Configurable parameters for the test
Parameters	Description
Test period	How often should the test be executed. By default, this is set to 60 minutes.
Host	The IP address of the Microsoft SQL server.
Port	The port number through which the Microsoft SQL server communicates. The default port is 1433.
User	If a Microsoft SQL Server 7.0/2000 is monitored, then provide the name of a SQL user with the Sysadmin role in this text box. While monitoring a Microsoft SQL Server 2005 or above, provide the name of a SQL user with all of the privileges outlined in User Privileges Required for Monitoring Microsoft SQL server.
Password	Specify the password corresponding to the mentioned user.
Confirm Password	Confirm the password by retyping it.
Instance	Enter the name of a specific Microsoft SQL instance that is to be monitored against this parameter. The default value of this parameter is “default”. To monitor a Microsoft SQL instance named “CFS”, enter this as the value of the Instance parameter.
Domain	By default, none is displayed in the Domain text box. If the ‘SQL server and Windows’ authentication has been enabled for the server being monitored, then the Domain can continue to be none. On the other hand, if ‘Windows only’ authentication has been enabled, then, in the Domain text box, specify the Windows domain in which the managed Microsoft SQL server exists. Also, in such a case, the User name and Password that you provide should be that of a user authorized to access the monitored SQL server.
ISNTLMV2	In some Windows networks, NTLM (NT LAN Manager) may be enabled. NTLM is a suite of Microsoft security protocols that provides authentication, integrity, and confidentiality to users. NTLM version 2 (“NTLMv2”) was concocted to address the security issues present in NTLM. By default, the ISNTLMV2 flag is set to No, indicating that NTLMv2 is not enabled by default on the target Microsoft SQL host. Set this flag to Yes if NTLMv2 is enabled on the target host.
IsPassive	If the value chosen is Yes, then the Microsoft SQL server under consideration is a passive server in a SQL cluster. No alerts will be generated if the server is not running. Measures will be reported as “Not applicable" by the agent if the server is not up.
SSL	By default, the SSL flag is set to No, indicating that the target Microsoft SQL server is not SSL-enabled by default. To enable the test to connect to an SSL-enabled Microsoft SQL server, set the SSL flag to Yes.
Force Strict Encryption	Specify Yes if you want to enforce strict encryption for communication. Default is No.
Hostname in Certificate	Specify the hostname that the certificate is issued for.
Truststore Filename	This parameter is applicable only if SSL-enabled channel is used for communication to the target SQL server, if not, set this parameter to none. Truststore is used to store certificates from Certified Authorities (CA) that verify and authenticate the certificate presented by the server in an SSL connection. Therefore, the eG agent should have access to the truststore where the certificates are stored to authenticate and connect with the target server and collect metrics. For this, first extract the certificates from the server into the following default location /opt/egurkha/jre/lib/security/egmqsslstore.jks.
Truststore Password and Confirm Password	If a Truststore File name or file path is provided, then, in this text box, provide the password that is used to obtain the associated certificate details from the Truststore File. Confirm the password by retyping it in this text box.
Include auto create stats	Specify Yes if you want to include auto created stats. The default is No.
Outdated stats by days	Specify the number of days after which the stats will be considered outdated.
Percentage of outdated stats by rows	Specify the percentage of rows if changed, the stats will be considered outdated.
Include DB	Specify the comma-separated list of databases that are to be included for monitoring in the Include DB text box. By default, the value of this parameter is none.
Exclude DB	Specify the comma-separated list of databases that are to be excluded for monitoring in the Excluded DB text box. By default, the value of this parameter is none.
Timeout (Seconds)	Specify the duration (in seconds) for which this test should wait for a response from the SQL server in the Timeout text box. If there is no response from the server beyond the configured duration, the test will timeout. By default, this is set to 120 seconds.
DD Frequency	Refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD frequency.
Detailed Diagnosis	To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option. The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled: The eG manager license should allow the detailed diagnosis capability Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.

Measurements made by the test
Measurement	Description	Measurement Unit	Interpretation
Outdated statistics by day	Indicates the number of outdated stats per day	Number
Outdated statistics by row modified	Indicates the number of outdated stats per row modified.	Number	Monitoring this percentage helps DBAs: Predict when stats will auto-update. Decide if manual updates are needed. Maintain optimal query performance.