SQL Sentry Portal Top SQL
Introduction
The Top SQL view displays a unified picture of collected SQL statements. It's designed to help you quickly identify queries, applications, logins, and more that are causing the most waits, using the most resources, taking the most time, and putting the most load on your SQL Server.
Available Charts
The full viewing options for this card's charts are:
- Queries ›
- By App ›
- By DB ›
- By Host ›
- By Login ›
- Resources
Select the ellipsis button in the upper right for additional options such as reset, show/hide axis labels, and show/hide axes.
Show/hide axes has the following options:
- Avg Duration (ms)
- CPU Time (ms)
- Exec Count
- Reads Logical
- Writes Logical
- Reads Physical
On the options with the > (chevron-right), additional choices similar to the above are available by selecting the > symbol. For example, By App - Duration (ms) and Queries - Reads (P) are available chart options.
Queries
Select the > (chevron-right) to view charts for:
- CPU
- Duration
- Exec Count
- Reads (L) - The default selection
- Reads (P)
- Writes (L)
The information displayed here is from query stats, procedure stats, and trace data.
Hover over an area in the chart to view more details about the queries:
By App
Select the > (chevron-right) to view charts for:
- CPU
- Duration
- Exec Count
- Reads (L) - The default selection
- Writes (L)
- Waits
The information displayed here is from trace data.
Hover over an area on the chart to view more details about the applications:
By DB
Select the > (chevron-right) to view charts for:
- CPU
- Duration
- Exec Count
- Reads (L) - The default selection
- Reads (P)
- Waits
Hover over an area on the chart to view more details about the databases:
By Host
Select the > (chevron-right) to view charts for:
- CPU
- Duration
- Exec Count
- Reads (L) - The default selection
- Writes (P)
- Waits
The information displayed here is from trace data.
Hover over an area on the chart to view more details about hosts:
By Login
Select the > (chevron-right) to view charts for:
- CPU
- Duration
- Exec Count
- Reads (L) - The default selection
- Writes (P)
- Waits
The information displayed here is from trace data.
Hover over an area on the chart to view more details about logins:
Resources
View resource usage from Top SQL, based on query and procedure stats:
Hover over a point on the chart to view additional details about the resources being used:
Waits
Waits charts can be selected as a category from the Queries, By App, By DB, By Host, or By login options.
Waits Categories
Starting with Version 2023.3, view detailed Wait information by the following categories below.
Waits By App
View Waits By App to see the applications that were contributing to the wait(s), and the wait durations in milliseconds (ms).
Waits By DB
View Waits By DB to identify the database where the wait(s) occurred and see the overall wait durations in milliseconds (ms).
Waits By Host
View Waits By Host to identify the host where the wait(s) occurred and see the overall wait durations in milliseconds.
Waits By Login
View Waits By Login to determine the login contributing to the wait(s) and see the overall wait durations in milliseconds (ms).
Completed Queries
The Completed Queries tab lists all recorded completed queries matching the current filters across the selected time period. The Completed Queries tab is displayed on the Top SQL tab by default. There are two modes for this pane: Totals and Trace Events.
The Totals table lists all events for the active date range in a standard list format, sorted descending by Reads by default. The Totals table is activated whenever auto-refresh is enabled by selecting Play on the toolbar, which shows the events for the last hour with new events coming in automatically at the top of the list.
The Completed Queries tab also displays any recorded Statements, Query History, or Plan Diagram information for recorded Completed Queries.
Proc/Query stats
Click Proc/Query Stats to display the Proc/Query Stats tab. The Proc/Query Stats tab provides aggregate information for all procedures and queries matching the current filters. This area also provides insight into queries that run very quickly and in high volume.
The Proc/Query stats tab displays a Totals table and Statements table for all recorded Proc/Query stats. The Proc/Query Stats tab also displays any Query History, or Plan Diagram information for the Proc/Query Stats.
Totals
The Totals table displays by default in both the Completed Queries and Proc/Query Stats tabs. The Totalstable displays the text data and associated information such as database, duration, count, and CPU for the collected SQL statements (including procedure stats, query stats, and completed queries). This groups all like events together using a normalized version of the T-SQL with all variable parameters replaced, and it shows aggregates for each group. This enables you to quickly determine which events are responsible for the most CPU or IO activity for the active date range.
Click a recorded event to display all of the recorded instances of that event. Click the Trace Events toggle to display the Trace Events for your selection.
Totals Filtering
Use the search bar to further filter your Top SQL totals. Type your search parameters into the search bar and select enter to filter the Totals grid.
Select the filter button on the Database category to filter by individual databases.
Select the databases that you want to filter by, and then select Apply to filter the Totals chart by your selection.
Statements
The Statements table displays additional information about Completed Queries or Proc/Query Stats where applicable, including plan diagrams, text data, parameters, and plan XML. The Statements table displays the statements that were collected with the associated completed query, procedure stats or query stats. It provides details on the key performance metrics that are associated with each component part of the larger query. This allows you to see which resources were consumed by which part of the batch.
Trace Events
Click the toggle in the Totals chart (
) on the Completed Queries tab to flip all totals and statements tables to the detailed Trace Events and Trace Events Statements tables on the Top SQL page and display details for any collected Trace Events such as RPC:Completed.
Trace Events Statements
Click the toggle in the Totals chart ( ) on the Completed Queries tab to flip all totals and statements tables to the detailed Trace Events and Trace Events Statements tables and display statement details to any collected Trace Events such as SP:StmtCompleted.
Trace Event Waits
Select a Trace Event Wait (ms) link to open the Trace Event Waits chart for your selection.
The Trace Event Waits chart displays detailed information about the recorded Trace Event Wait including the text data, duration, waits (ms), reads, and writes.
Trace Event Filtering
Select the filter button on the desired category to filter by that category. For example, select the filter button for the hosts category, select the desired hosts, then select Apply to apply the filter to the Trace Events grid.
Query History
Select a query or statement, then view the Query History for it. Query History displays a graphical representation of the selected query over a specified range of time. Query History provides information about the query execution plans, if and when they were changed, and how they impacted different resources.
Query Event
Each triangle represents a Query Event.
Query Stats Sample
Each dot represents a Query Stats Sample or a Proc Stats Sample.
Proc Stats Sample
Each dot represents a Proc Stats Sample or a Query Stats Sample.
Additional Options
Use the options below the chart to adjust the Grouping, Show, Metric, Mode, or Dates slider window.
- Grouping
- None
- Hour
- Day
- Week
- None
- Show
- Actual/Average
- Totals
- Actual/Average
- Metric
- Duration
- CPU
- IO
- Duration
- Mode
- Procedure
- Statement
- Procedure
Example with Grouping by Hour, ShowTotals, MetricCPU, and ModeStatement:
An additional example with multiple plans represented:
Additional Information:
- Multiple Plans for an "Identical" Query blog post by Aaron Bertrand on SQLPerformance
- Different Plans for "Identical" Servers blog post by Aaron Bertrand on SQL Performance
- Analyzing "death by a thousand cuts" workloads blog post by Erin Stellato on SQLPerformance
- How useful are query_hash and query_plan_hash for troubleshooting? blog post by Jonathan Kehayias on SQLskills
Plan Diagram
Use the full screen button in the upper left to expand a larger plan, or use the Download Plan button to download the entire .sqlplan file.
Note:
- Sometimes the plan XML may be populated, but there's not a statement that can be matched for the plan diagram. This can be caused by things like nested procedures or individual statements falling outside of the collection thresholds on their own. In this case, the plan diagram will display a message such as "The selected statement was not found in the plan XML. Download the full plan to view in Plan Explorer" and provide a Download Plan XML button.
- If the Query History chart shows a disabled point (i.e. a gray triangle), then the plan diagram will display a message to indicate that there are no plans available (e.g. "There is no data to display").
Text Data
Use the Text Data tab to view a formatted and syntax color-coded copy of the statement.
Parameters
Use the Parameters tab to view compiled values for statement parameters.
Plan XML
Use the Plan XML tab to view or copy the ShowPlanXML output.
