人人都是 DBA（XII）查詢信息收集腳本匯編

什么？有個 SQL 執行了 8 秒！

哪里出了問題？臣妾不知道啊，得找 DBA 啊。

DBA 人呢？離職了！！擦！！！

程序員在無處尋求幫助時，就得想辦法自救，努力讓自己變成 "偽 DBA"。

索引

1. 按頁編號查看數據表信息
2. 獲取查詢 SELECT 語句的執行次數排名
3. 看看哪些 Ad-hoc Query 在浪費資源
4. 查看當前處於等待狀態的 Task 在等什么
5. 查詢誰在占着 Session 連接
6. 查詢程序占用的 SPID 信息
7. 查詢所有執行 SQL 對應的 sql_handle
8. 查詢最近 60 秒平均執行時間超過 300 毫秒的 SQL 語句
9. 查詢最近 60 秒平均執行時間超過 100 毫秒的非 SELECT 語句
10. 查詢最近 60 秒累計總執行次數大於 1000 次的 SQL 語句
11. 查詢前 10 個可能是性能最差的 SQL 語句
12. 看看當前哪些查詢正在活躍着

按頁編號查看數據表信息

SELECT sc.[name] AS [schema]
    ,o.[name] AS [table_name]
    ,o.type_desc
    ,obd.[file_id]
    ,obd.page_id
    ,obd.page_level
    ,obd.row_count
    ,obd.free_space_in_bytes
    ,obd.is_modified
    ,obd.numa_node
FROM sys.dm_os_buffer_descriptors AS obd
JOIN sys.allocation_units AS au ON obd.allocation_unit_id = au.allocation_unit_id
JOIN sys.partitions AS p ON au.container_id = p.partition_id
JOIN sys.objects AS o ON p.[object_id] = o.[object_id]
JOIN sys.schemas AS sc ON o.[schema_id] = sc.[schema_id]
WHERE database_id = DB_ID()
    AND o.is_ms_shipped = 0
ORDER BY obd.page_id
    ,o.[name]

獲取查詢 SELECT 語句的執行次數排名

SQL Server 2012 版本

SELECT TOP (100) qs.execution_count
    ,qs.total_rows
    ,qs.last_rows
    ,qs.min_rows
    ,qs.max_rows
    ,qs.last_elapsed_time
    ,qs.min_elapsed_time
    ,qs.max_elapsed_time
    ,total_worker_time
    ,total_logical_reads
    ,SUBSTRING(qt.[text], qs.statement_start_offset / 2 + 1, (
            CASE 
                WHEN qs.statement_end_offset = - 1
                    THEN LEN(CONVERT(NVARCHAR(MAX), qt.[text])) * 2
                ELSE qs.statement_end_offset
                END - qs.statement_start_offset
            ) / 2) AS query_text
FROM sys.dm_exec_query_stats AS qs WITH (NOLOCK)
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS qt
ORDER BY qs.execution_count DESC
OPTION (RECOMPILE);

SQL Server 2008 R2 版本

SELECT TOP (100) qs.execution_count
    ,qs.last_elapsed_time
    ,qs.min_elapsed_time
    ,qs.max_elapsed_time
    ,total_worker_time
    ,total_logical_reads
    ,SUBSTRING(qt.[text], qs.statement_start_offset / 2 + 1, (
            CASE 
                WHEN qs.statement_end_offset = - 1
                    THEN LEN(CONVERT(NVARCHAR(MAX), qt.[text])) * 2
                ELSE qs.statement_end_offset
                END - qs.statement_start_offset
            ) / 2) AS query_text
FROM sys.dm_exec_query_stats AS qs WITH (NOLOCK)
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS qt
ORDER BY qs.execution_count DESC
OPTION (RECOMPILE);

看看哪些 Ad-hoc Query 在浪費資源

SELECT TOP (50) [text] AS [QueryText]
    ,cp.cacheobjtype
    ,cp.objtype
    ,cp.size_in_bytes / 1024 AS [Plan Size in KB]
FROM sys.dm_exec_cached_plans AS cp WITH (NOLOCK)
CROSS APPLY sys.dm_exec_sql_text(plan_handle)
WHERE cp.cacheobjtype = N'Compiled Plan'
    AND cp.objtype IN (
        N'Adhoc'
        ,N'Prepared'
        )
    AND cp.usecounts = 1
ORDER BY cp.size_in_bytes DESC
OPTION (RECOMPILE);

查看當前處於等待狀態的 Task 在等什么

SELECT dm_ws.wait_duration_ms
    ,dm_ws.wait_type
    ,dm_es.STATUS
    ,dm_t.TEXT
    ,dm_qp.query_plan
    ,dm_ws.session_ID
    ,dm_es.cpu_time
    ,dm_es.memory_usage
    ,dm_es.logical_reads
    ,dm_es.total_elapsed_time
    ,dm_es.program_name
    ,DB_NAME(dm_r.database_id) DatabaseName
    ,dm_ws.blocking_session_id
    ,dm_r.wait_resource
    ,dm_es.login_name
    ,dm_r.command
    ,dm_r.last_wait_type
FROM sys.dm_os_waiting_tasks dm_ws
INNER JOIN sys.dm_exec_requests dm_r ON dm_ws.session_id = dm_r.session_id
INNER JOIN sys.dm_exec_sessions dm_es ON dm_es.session_id = dm_r.session_id
CROSS APPLY sys.dm_exec_sql_text(dm_r.sql_handle) dm_t
CROSS APPLY sys.dm_exec_query_plan(dm_r.plan_handle) dm_qp
WHERE dm_es.is_user_process = 1;

查詢誰在占着 Session 連接

CREATE TABLE #sp_who2 (
    SPID INT
    ,STATUS VARCHAR(255)
    ,LOGIN VARCHAR(255)
    ,HostName VARCHAR(255)
    ,BlkBy VARCHAR(255)
    ,DBName VARCHAR(255)
    ,Command VARCHAR(255)
    ,CPUTime INT
    ,DiskIO INT
    ,LastBatch VARCHAR(255)
    ,ProgramName VARCHAR(255)
    ,SPID2 INT
    ,REQUESTID INT
    )

INSERT INTO #sp_who2
EXEC sp_who2

SELECT *
FROM #sp_who2 w
--WHERE w.ProgramName = 'xxx'

DROP TABLE #sp_who2

查詢程序占用的 SPID 信息

SELECT spid
    ,a.[status]
    ,hostname
    ,program_name
    ,cmd
    ,cpu
    ,physical_io
    ,blocked
    ,b.[name]
    ,loginame
FROM master.dbo.sysprocesses a
INNER JOIN master.dbo.sysdatabases b ON a.dbid = b.dbid
where hostname != ''
ORDER BY program_name

查詢所有執行 SQL 對應的 sql_handle

DECLARE @current_sql_handle BINARY (20);
DECLARE @sql_text_list TABLE (
    sql_handle BINARY (20)
    ,TEXT NVARCHAR(max)
    );

DECLARE sql_handle_cursor CURSOR
FOR
SELECT sp.sql_handle
FROM sys.sysprocesses sp
WHERE sp.sql_handle != 0x0000000000000000000000000000000000000000
    --AND sp.program_name = 'xxxx'
    ;

OPEN sql_handle_cursor

FETCH NEXT
FROM sql_handle_cursor
INTO @current_sql_handle

WHILE @@FETCH_STATUS = 0
BEGIN
    INSERT INTO @sql_text_list (
        sql_handle
        ,TEXT
        )
    SELECT @current_sql_handle
        ,est.TEXT
    FROM sys.dm_exec_query_stats qs
    CROSS APPLY sys.dm_exec_sql_text(@current_sql_handle) est;

    FETCH NEXT
    FROM sql_handle_cursor
    INTO @current_sql_handle
END

SELECT DISTINCT *
FROM @sql_text_list tl
WHERE tl.TEXT NOT LIKE '%statement_start_offset%';

CLOSE sql_handle_cursor

DEALLOCATE sql_handle_cursor

查詢最近 60 秒平均執行時間超過 300 毫秒的 SQL 語句

SELECT SUBSTRING(st.TEXT, (qs.statement_start_offset / 2) + 1, (
            (
                (
                    CASE statement_end_offset
                        WHEN - 1
                            THEN DATALENGTH(st.TEXT)
                        ELSE qs.statement_end_offset
                        END
                    ) - qs.statement_start_offset
                ) / 2
            ) + 1) AS statement_text
    ,last_execution_time
    ,total_elapsed_time / execution_count avg_elapsed_time
    ,total_physical_reads
    ,total_logical_reads
    ,total_logical_writes
    ,execution_count
    ,total_worker_time
    ,total_elapsed_time
    ,creation_time
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st
WHERE last_execution_time > DATEADD(SECOND, - 60, GETDATE())
    AND st.TEXT NOT LIKE '%statement_start_offset%'
    AND total_elapsed_time / execution_count >= 300
ORDER BY last_execution_time DESC;

查詢最近 60 秒平均執行時間超過 100 毫秒的非 SELECT 語句

SELECT SUBSTRING(st.TEXT, (qs.statement_start_offset / 2) + 1, (
            (
                (
                    CASE statement_end_offset
                        WHEN - 1
                            THEN DATALENGTH(st.TEXT)
                        ELSE qs.statement_end_offset
                        END
                    ) - qs.statement_start_offset
                ) / 2
            ) + 1) AS statement_text
    ,last_execution_time
    ,total_elapsed_time / execution_count avg_elapsed_time
    ,total_physical_reads
    ,total_logical_reads
    ,total_logical_writes
    ,execution_count
    ,total_worker_time
    ,total_elapsed_time
    ,creation_time
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st
WHERE last_execution_time > DATEADD(SECOND, - 60, GETDATE())
    AND st.TEXT NOT LIKE '%statement_start_offset%'
    AND execution_count < 100
    AND total_elapsed_time / execution_count > 100
    AND SUBSTRING(st.TEXT, (qs.statement_start_offset / 2) + 1, (
            (
                (
                    CASE statement_end_offset
                        WHEN - 1
                            THEN DATALENGTH(st.TEXT)
                        ELSE qs.statement_end_offset
                        END
                    ) - qs.statement_start_offset
                ) / 2
            ) + 1) NOT LIKE 'SELECT%'
ORDER BY last_execution_time DESC;

查詢最近 60 秒累計總執行次數大於 1000 次的 SQL 語句

SELECT SUBSTRING(st.TEXT, (qs.statement_start_offset / 2) + 1, (
            (
                (
                    CASE statement_end_offset
                        WHEN - 1
                            THEN DATALENGTH(st.TEXT)
                        ELSE qs.statement_end_offset
                        END
                    ) - qs.statement_start_offset
                ) / 2
            ) + 1) AS statement_text
    ,total_elapsed_time / execution_count / 1000 AS avg_elapsed_time_by_ms
    ,last_execution_time
    ,total_elapsed_time
    ,execution_count
    ,total_worker_time
    ,total_physical_reads
    ,total_logical_reads
    ,total_logical_writes
    ,creation_time
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st
WHERE qs.execution_count > 1000
    AND last_execution_time > DATEADD(SECOND, - 60, GETDATE())
    --AND (
    --    st.TEXT LIKE '%[[]AAA]%'
    --    OR st.TEXT LIKE '%[[]BBB]%'
    --    OR st.TEXT LIKE '%[[]CCC]%'
    --    )
ORDER BY total_elapsed_time / execution_count DESC;

查詢前 10 個可能是性能最差的 SQL 語句

SELECT TOP 10 TEXT AS 'SQL Statement'
    ,last_execution_time AS 'Last Execution Time'
    ,(total_logical_reads + total_physical_reads + total_logical_writes) / execution_count AS [Average IO]
    ,(total_worker_time / execution_count) / 1000000.0 AS [Average CPU Time (sec)]
    ,(total_elapsed_time / execution_count) / 1000000.0 AS [Average Elapsed Time (sec)]
    ,execution_count AS "Execution Count"
    ,qp.query_plan AS "Query Plan"
FROM sys.dm_exec_query_stats qs
CROSS APPLY sys.dm_exec_sql_text(qs.plan_handle) st
CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) qp
ORDER BY total_elapsed_time / execution_count DESC

看看當前哪些查詢正在活躍着

Adam Machanic 發布了一個查詢活躍 SQL 的查詢腳本，篇幅極長，請到發布地址下載。

• Who is Active v11.11

 

《人人都是 DBA》系列文章索引：

序號	名稱
1	人人都是 DBA（I）SQL Server 體系結構
2	人人都是 DBA（II）SQL Server 元數據
3	人人都是 DBA（III）SQL Server 調度器
4	人人都是 DBA（IV）SQL Server 內存管理
5	人人都是 DBA（V）SQL Server 數據庫文件
6	人人都是 DBA（VI）SQL Server 事務日志
7	人人都是 DBA（VII）B 樹和 B+ 樹
8	人人都是 DBA（VIII）SQL Server 頁存儲結構
9	人人都是 DBA（IX）服務器信息收集腳本匯編
10	人人都是 DBA（X）資源信息收集腳本匯編
11	人人都是 DBA（XI）I/O 信息收集腳本匯編
12	人人都是 DBA（XII）查詢信息收集腳本匯編
13	人人都是 DBA（XIII）索引信息收集腳本匯編
14	人人都是 DBA（XIV）存儲過程信息收集腳本匯編
15	人人都是 DBA（XV）鎖信息收集腳本匯編

本系列文章《人人都是 DBA》由 Dennis Gao 發表自博客園，未經作者本人同意禁止任何形式的轉載，任何自動或人為的爬蟲轉載行為均為耍流氓。