Skip to content

sp_BlitzCache: Fix ai_prompt returning nulls when @AI > 0 #3856

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
Copilot wants to merge 2 commits into from
Closed

sp_BlitzCache: Fix ai_prompt returning nulls when @AI > 0 #3856

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
a8bc5f1
Initial plan
Copilot Mar 16, 2026
883ae87
Fix ai_prompt returning nulls when @AI > 0 in sp_BlitzCache
Copilot Mar 16, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
32 changes: 22 additions & 10 deletions sp_BlitzCache.sql
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5201,7 +5201,7 @@ BEGIN
SELECT DISTINCT DatabaseName
FROM ##BlitzCacheProcs
WHERE SPID = @@SPID
AND QueryPlan IS NOT NULL
AND (QueryPlan IS NOT NULL OR QueryText IS NOT NULL)
AND DatabaseName IS NOT NULL;

OPEN ai_db_cursor;
Expand Down Expand Up @@ -5330,17 +5330,16 @@ Plan Info:
Here are the warnings that popular query analysis tool sp_BlitzCache detected and suggested that we focus on - although there may be more issues, too: ' + ISNULL(Warnings, N'None') + N'

Query Text (which is cut off for long queries):
' + ISNULL(LEFT(QueryText, 4000), N'N/A') + N'
' + CASE WHEN QueryText IS NULL THEN N'(Query text could not be retrieved.)' ELSE LEFT(QueryText, 4000) END + N'

' + CASE WHEN QueryType LIKE N'Statement (parent%' THEN N' The above query is part of a batch, stored procedure, or function, so other queries may show up in the query plan. However, those other queries are irrelevant here. Focus on this specific query above, because it is one of the most resource-intensive queries in the batch. The execution plan below includes other statements in the batch, but ignore those and focus only the query above and its specific plan in the batch below. ' ELSE N' ' END + N'

XML Execution Plan:
' + ISNULL(CAST(QueryPlan AS NVARCHAR(MAX)), N'N/A') + N'
' + CASE WHEN QueryPlan IS NULL THEN N'(Query plan could not be retrieved.)' ELSE CAST(QueryPlan AS NVARCHAR(MAX)) END + N'

Thank you.'
FROM ##BlitzCacheProcs p
WHERE p.SPID = @@SPID
AND (@AI = 2 OR p.QueryPlan IS NOT NULL) /* For @AI = 1, skip null plans (no value calling AI without a plan); for @AI = 2, build prompts even when plan is null */
AND NOT (p.QueryType LIKE 'Procedure or Function:%' /* This and the below exists query makes sure that we don't get advice for parent procs, only their statements, if the statements are in our result set. */
AND EXISTS
(
Expand Down Expand Up @@ -5369,6 +5368,14 @@ Thank you.'
)
OPTION (RECOMPILE);

/* If both query text and query plan are null, override with a simple message - no metrics or system prompt needed */
UPDATE ##BlitzCacheProcs
SET ai_prompt = N'Prompt not generated because we can''t find the query text or query plan.'
WHERE SPID = @@SPID
AND QueryText IS NULL
AND QueryPlan IS NULL
OPTION (RECOMPILE);

IF @Debug = 2
SELECT 'After setting up ai_prompt, before calling AI' AS ai_stage, SqlHandle, QueryHash, PlanHandle, QueryPlan, ai_prompt, ai_advice, ai_raw_response
FROM ##BlitzCacheProcs
Expand All @@ -5391,8 +5398,8 @@ Thank you.'
SELECT DISTINCT SqlHandle, QueryHash, PlanHandle, ai_prompt, COALESCE(QueryType, N'') + N' - ' + LEFT(QueryText, 100)
FROM ##BlitzCacheProcs
WHERE SPID = @@SPID
AND QueryPlan IS NOT NULL
AND ai_prompt IS NOT NULL;
AND ai_prompt IS NOT NULL
AND (QueryPlan IS NOT NULL OR QueryText IS NOT NULL);

OPEN ai_cursor;

Expand Down Expand Up @@ -5531,6 +5538,7 @@ Thank you.'
SET ai_advice = N'AI prompt generated but not sent (running with @AI = 2). Review the ai_prompt column for the prompt that would be sent.'
WHERE SPID = @@SPID
AND ai_prompt IS NOT NULL
AND (QueryPlan IS NOT NULL OR QueryText IS NOT NULL)
OPTION (RECOMPILE);
END;
END;
Expand Down Expand Up @@ -5729,8 +5737,10 @@ BEGIN
implicit_conversion_info AS [Implicit Conversion Info],
cached_execution_parameters AS [Cached Execution Parameters], '
+ CASE WHEN @AI = 2 THEN N'
[AI Prompt] = (
SELECT (@AISystemPrompt + NCHAR(13) + NCHAR(10) + NCHAR(13) + NCHAR(10) + ai_prompt) AS [text()] FOR XML PATH(''ai_prompt''), TYPE),' ELSE N'' END
[AI Prompt] = CASE WHEN QueryText IS NULL AND QueryPlan IS NULL THEN (
SELECT ai_prompt AS [text()] FOR XML PATH(''ai_prompt''), TYPE)
ELSE (
SELECT (@AISystemPrompt + NCHAR(13) + NCHAR(10) + NCHAR(13) + NCHAR(10) + ai_prompt) AS [text()] FOR XML PATH(''ai_prompt''), TYPE) END,' ELSE N'' END
+ CASE WHEN @AI = 1 THEN N'
[AI Advice] = CASE WHEN ai_advice IS NULL THEN NULL ELSE (
SELECT ai_advice AS [text()] FOR XML PATH(''ai_advice''), TYPE) END, ' ELSE N'' END
Expand Down Expand Up @@ -5865,8 +5875,10 @@ BEGIN
StatementEndOffset,
PlanGenerationNum, '
+ CASE WHEN @AI <> 2 THEN N'
[AI Prompt] = (
SELECT (@AISystemPrompt + NCHAR(13) + NCHAR(10) + NCHAR(13) + NCHAR(10) + ai_prompt) AS [text()] FOR XML PATH(''ai_prompt''), TYPE),' ELSE N'' END
[AI Prompt] = CASE WHEN QueryText IS NULL AND QueryPlan IS NULL THEN (
SELECT ai_prompt AS [text()] FOR XML PATH(''ai_prompt''), TYPE)
ELSE (
SELECT (@AISystemPrompt + NCHAR(13) + NCHAR(10) + NCHAR(13) + NCHAR(10) + ai_prompt) AS [text()] FOR XML PATH(''ai_prompt''), TYPE) END,' ELSE N'' END
+ CASE WHEN @AI = 1 THEN N'
[AI Payload] = CASE WHEN ai_payload IS NULL THEN NULL ELSE (
SELECT ai_payload AS [text()] FOR XML PATH(''ai_payload''), TYPE) END,
Expand Down