Search plan cache for all query plans using a given index?

All we need is an easy explanation of the problem, so here it is.

Is there a query I can run to search the plan cache for all query plans using a given index?

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

I’d recommend using sys.dm_exec_text_query_plan instead of sys.dm_exec_query_plan. Using sys.dm_exec_query_plan you will lose stored procedures with deferred compilation, long-running stored procedures (in case the SP has not finished but its statement which is using the given index has already done), and multi-statement UDF.

Additionally, you should add hints to avoid possible negative influence on your working environment.

SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
DECLARE @IndexName AS NVARCHAR(128) = N'[YourIndexName]';

;WITH XMLNAMESPACES 
   (DEFAULT 'http://schemas.microsoft.com/sqlserver/2004/07/showplan')    
SELECT 
DB_NAME(x.dbid),
x.ObjectName,
stmt.value('(@StatementText)[1]', 'varchar(max)') AS SQL_Text, 
obj.value('(@Database)[1]', 'varchar(128)') AS DatabaseName, 
obj.value('(@Schema)[1]', 'varchar(128)') AS SchemaName, 
obj.value('(@Table)[1]', 'varchar(128)') AS TableName, 
obj.value('(@Index)[1]', 'varchar(128)') AS IndexName, 
obj.value('(@IndexKind)[1]', 'varchar(128)') AS IndexKind, 
x.plan_handle, 
x.query_plan 
FROM (
    SELECT try_CONVERT(XML, qp.query_plan) AS query_plan, cp.plan_handle, OBJECT_NAME(qp.objectid, qp.dbid) AS ObjectName, qp.objectid, qp.dbid
    FROM sys.dm_exec_cached_plans AS cp 
        JOIN sys.dm_exec_query_stats s ON s.plan_handle = cp.plan_handle
        cross apply sys.dm_exec_text_query_plan (s.plan_handle, s.statement_start_offset, s.statement_end_offset) AS qp 
) x
CROSS APPLY query_plan.nodes('/ShowPlanXML/BatchSequence/Batch/Statements/StmtSimple') AS batch(stmt) 
CROSS APPLY stmt.nodes('.//IndexScan/Object[@Index=sql:variable("@IndexName")]') AS idx(obj) 
OPTION(MAXDOP 1, RECOMPILE);

Method 2

As well as a simple text search, you can also use an XQuery filter, which may be faster or slower.

DECLARE @idx sysname = N'[IX_YourIndexName]';

WITH XMLNAMESPACES(DEFAULT 'http://schemas.microsoft.com/sqlserver/2004/07/showplan')
SELECT
    qp.query_plan,
    qs.execution_count,
    st.text
FROM sys.dm_exec_cached_plans cp
CROSS APPLY sys.dm_exec_query_plan(cp.plan_handle) qp
INNER JOIN sys.dm_exec_query_stats qs ON qs.plan_handle = cp.plan_handle
CROSS APPLY sys.dm_exec_sql_text(cp.plan_handle) st
WHERE qp.query_plan.exist('//Object[@Index = sql:variable("@idx")]') = 1;

Or if you want just the query plans:

DECLARE @idx sysname = N'[IX_YourIndexName]';

WITH XMLNAMESPACES(DEFAULT 'http://schemas.microsoft.com/sqlserver/2004/07/showplan')
SELECT
    qp.query_plan
FROM sys.dm_exec_cached_plans cp
CROSS APPLY sys.dm_exec_query_plan(cp.plan_handle) qp
WHERE qp.query_plan.exist('//Object[@Index = sql:variable("@idx")]') = 1;

You can also add filters on @Database and @Schema if necessary.

If you are copying the index name out of system views, make sure to use QUOTENAME otherwise it won’t match.

Method 3

try this:

SELECT
    dm_exec_query_plan.query_plan,
    usecounts AS execution_count,
    dm_exec_sql_text.text
FROM sys.dm_exec_cached_plans
CROSS APPLY sys.dm_exec_query_plan(plan_handle)
INNER JOIN sys.dm_exec_query_stats
ON dm_exec_query_stats.plan_handle = dm_exec_cached_plans.plan_handle
CROSS APPLY sys.dm_exec_sql_text(dm_exec_query_stats.plan_handle)
WHERE CAST(dm_exec_query_plan.query_plan AS NVARCHAR(MAX)) LIKE '%index_you_are_looking_for%'
  • beware of indexes with similar names like this: named CIX_Customer_CreateDate and IX_CustomerAddress will return from a search for LIKE '%IX_Customer%'

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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