SQL Missing Indexes Test

SQL Server allows you to put indexes on table columns, to speed up WHERE and JOIN statements on those columns. If a SQL query takes longer (much longer) to complete, it could be because one/more of these indexes are ‘missing’. When the query optimizer optimizes a query, it identifies those indexes it would have liked to have used but were not available - these are called ‘missing indexes’.

With the help of the SQL Missing Indexes test, you can be promptly alerted when the query optimizer finds one/more ‘missing indexes’. Besides reporting the count of the missing indexes, the test also reveals which queries require these indexes, thus enabling you to quickly initiate index creation and  query optimization.

This test is disabled by default. To enable the test, go to the enable / disable tests page using the menu sequence : Agents -> Tests -> Enable/Disable, pick Microsoft SQL as the Component type, Performance as the Test type, choose this test from the disabled tests list, and click on the << button to move the test to the ENABLED TESTS list. Finally, click the Update button.

Target of the test : A Microsoft SQL server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for every database on the monitored Microsoft SQL server

  1. TEST PERIOD - How often should the test be executed
  2. Host – The host for which the test is to be configured
  3. Port - The port on which the server is listening
  4. ssl – If the Microsoft SQL server being monitored is an SSL-enabled server, then set the ssl flag to Yes. If not, then set the ssl flag to No.
  5. 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.

  6. password - The password of the specified user
  7. confirm password - Confirm the password by retyping it.
  8. 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.
  9. excludepattern - Provide a comma-separated list of programs/processes on the SQL server that need to be excluded from monitoring. The default value is none, indicating that all processes are monitored by default. To make sure that the test ignores a few processes, specify the process names as a comma-separated list. For example: SQL_Query_Analyzer,jTDS. You can also use wild card patterns in your specification - for instance, SQL*,*TDS,Microsoft*.
  10. 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.
  11. 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.
  12. DETAILED DIAGNOSIS – To make diagnosis more efficient and accurate, the eG Enterprise suite 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

Number of Missing Indexes:

Indicates the total number of missing indexes found in the queries that are currently executing on this database.

Number

The detailed diagnosis of this measure reveals the tables and the specific columns in those tables that are missing indexes. If the missing indexes are adversely impacting query performance, then database administrators can use this information to decide on the ideal approach to improving query performance – should new indexes be created? Or should queries be optimized to use existing indexes?

Missing indexes based on user seeks

Indicates the number of times the missing indexes appeared in the result set of the queries based on user requests.

Number

 

Missing indexes based on user impact

Indicates the number of times the resources of the database server were impacted due to user queries when the indexes were missing.

Number