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SQL Server系统视图sys.master_files不能正确显示数据库脱机状态

2018-04-21 00:27 潇湘隐者 阅读(...) 评论(...) 编辑 收藏

 

最近发现在SQL Server数据库(目前测试过SQL Server 2008, 2012,2014,2016各个版本)中,即使数据库处于脱机(OFFLINE)状态,但是sys.master_files依然显示是联机状态。本文测试环境为Microsoft SQL Server 2014 (SP2) (KB3171021) - 12.0.5000.0 (X64) 。具体测试过程如下所示:

 

 

 
USE master;
GO
ALTER DATABASE TEST SET OFFLINE WITH ROLLBACK IMMEDIATE;
GO
 
 
SELECT  name ,
        physical_name ,
        state ,
        state_desc
FROM    sys.master_files
WHERE   database_id = DB_ID('test');
 
 
SELECT  name ,
        state ,
        state_desc
FROM    sys.databases
WHERE   name = 'test';

 

 

clip_image001

 

 

如上所示,sys.databases系统视图正确的显示数据库处于脱机状态(OFFLINE),但是系统视图sys.master_files显示的依然是联机(ONLINE),我们可以获取系统视图sys.master_files的定义,如下所示(至于如何获取视图定义,如果你不清楚,可以参考我的博客SQL Server查看视图定义总结),

 

 

 

SET QUOTED_IDENTIFIER ON
SET ANSI_NULLS ON
GO
 CREATE VIEW sys.master_files AS
    SELECT
        database_id         = f.dbid,
        file_id             = f.fileid,
        file_guid           = f.fileguid,
        type                = f.filetype,
        type_desc           = ft.name,
        data_space_id       = f.grpid,
        name                = f.lname,
        physical_name       = f.pname,
        state               = convert(tinyint, case f.filestate        -- Map enum EMDFileState to AvailablityStates
                                when 0 then 0 when 10 then 0    -- ONLINE
                                when 4 then 7    -- DEFUNCT
                                when 5 then 3 when 9 then 3    -- RECOVERY_PENDING
                                when 7 then 1 when 8 then 1 when 11 then 1    -- RESTORING
                                when 12 then 4    -- SUSPECT
                                else 6 end),    -- OFFLINE
        state_desc          = st.name,
        f.size,
        max_size            = f.maxsize,
        f.growth,
        is_media_read_only  = sysconv(bit, f.status & 8),        -- FIL_READONLY_MEDIA
        is_read_only        = sysconv(bit, f.status & 16),    -- FIL_READONLY
        is_sparse           = sysconv(bit, f.status & 256),    -- FIL_SPARSE_FILE
        is_percent_growth   = sysconv(bit, f.status & 32),    -- FIL_PERCENT_GROWTH
        is_name_reserved    = sysconv(bit, case f.filestate when 3 then 1 else 0 end), -- x_efs_DroppedReusePending
        create_lsn          = GetNumericLsn(f.createlsn),
        drop_lsn            = GetNumericLsn(f.droplsn),
        read_only_lsn       = GetNumericLsn(f.readonlylsn),
        read_write_lsn      = GetNumericLsn(f.readwritelsn),
        differential_base_lsn     = GetNumericLsn(f.diffbaselsn),
        differential_base_guid    = f.diffbaseguid,
        differential_base_time    = nullif(f.diffbasetime, 0),
        redo_start_lsn            = GetNumericLsn(f.redostartlsn),
        redo_start_fork_guid      = f.redostartforkguid,
        redo_target_lsn           = GetNumericLsn(f.redotargetlsn),
        redo_target_fork_guid     = f.forkguid,
        backup_lsn                = GetNumericLsn(f.backuplsn),
        credential_id             = cr.credential_id
    FROM sys.sysbrickfiles f
    LEFT JOIN sys.syspalvalues st ON st.class = 'DBFS' AND st.value = f.filestate
    LEFT JOIN sys.syspalvalues ft ON ft.class = 'DBFT' AND ft.value = f.filetype
    LEFT JOIN sys.credentials cr ON f.pname LIKE cr.name + N'%' COLLATE database_default
    WHERE f.dbid < 0x7fff -- consistent with sys.databases
        AND f.pruid = 0
        AND f.filestate NOT IN (1, 2)    -- x_efs_Dummy, x_efs_Dropped
        AND has_access('MF', 1) = 1
 
GO

 

 

可以看出sys.master_files的state值来自于系统基表sys.sysbrickfiles的filestate字段,我们从DAC模式去查看,发现TEST数据库(dbid=21)的filestat为0,这个值应该为6才对,另外,还有一个让人意外的是,这个系统表里面关于TEST数据库有两个事务日志文件记录,实际上只有一个(其实这个是前阵子写这篇博客MS SQL 事务日志管理小结时,测试添加、删除数据事务日志文件遗留下来的记录,不清楚是Bug还是什么问题导致在系统基表还存在这样的一条记录

 

 

 

clip_image002

 

 

 

那么我们接下来看看sys.sysbrickfiles的具体定义,如下所示:

 

SET QUOTED_IDENTIFIER ON
SET ANSI_NULLS ON
GO
CREATE VIEW sys.databases AS
    SELECT d.name, d.id AS database_id,
        r.indepid AS source_database_id,
        d.sid AS owner_sid,
        d.crdate AS create_date,
        d.cmptlevel AS compatibility_level,
        -- coll.value = null means that a collation wasn't specified for the DB and the server default is used instead
        convert(sysname, case when serverproperty('EngineEdition') = 5 AND d.id = 1 then serverproperty('collation')
                                 else CollationPropertyFromID(convert(int, isnull(coll.value, p.cid)), 'name') end) AS collation_name,
        p.user_access, ua.name AS user_access_desc,
        sysconv(bit, d.status & 0x400) AS is_read_only,            -- DBR_RDONLY
        sysconv(bit, d.status & 1) AS is_auto_close_on,            -- DBR_CLOSE_ON_EXIT
        sysconv(bit, d.status & 0x400000) AS is_auto_shrink_on,        -- DBR_AUTOSHRINK
        case when (serverproperty('EngineEdition') = 5) AND (sysconv(bit, d.status & 0x00000020) = 1) then cast (1 as tinyint) -- RESTORING
             when (serverproperty('EngineEdition') = 5) AND (sysconv(bit, d.status & 0x00000080) = 1) then cast (7 as tinyint) -- COPYING
             when (serverproperty('EngineEdition') = 5) AND (sysconv(bit, d.status & 0x00000100) = 1) then cast (4 as tinyint) -- SUSPECT
             else p.state 
             end AS state, -- 7 is COPYING and 4 is SUSPECT state for database copy (UNDO: Need to have a clean way to set states in dbtable for a user db)
        case when (serverproperty('EngineEdition') = 5) AND (sysconv(bit, d.status & 0x00000020) = 1) then 'RESTORING' 
             when (serverproperty('EngineEdition') = 5) AND (sysconv(bit, d.status & 0x00000080) = 1) then 'COPYING' 
             when (serverproperty('EngineEdition') = 5) AND (sysconv(bit, d.status & 0x00000100) = 1) then 'SUSPECT'
             else st.name 
             end AS state_desc,
        sysconv(bit, d.status & 0x200000) AS is_in_standby,        -- DBR_STANDBY
        case when serverproperty('EngineEdition') = 5 then convert(bit, 0) else p.is_cleanly_shutdown end AS is_cleanly_shutdown,
        sysconv(bit, d.status & 0x80000000) AS is_supplemental_logging_enabled,    -- DBR_SUPPLEMENT_LOG
        p.snapshot_isolation_state, si.name AS snapshot_isolation_state_desc,
        sysconv(bit, d.status & 0x800000) AS is_read_committed_snapshot_on,        -- DBR_READCOMMITTED_SNAPSHOT
        p.recovery_model, ro.name AS recovery_model_desc,
        p.page_verify_option, pv.name AS page_verify_option_desc,
        sysconv(bit, d.status2 & 0x1000000) AS is_auto_create_stats_on,            -- DBR_AUTOCRTSTATS
        sysconv(bit, d.status2 & 0x00400000) AS is_auto_create_stats_incremental_on,    -- DBR_AUTOCRTSTATSINC
        sysconv(bit, d.status2 & 0x40000000) AS is_auto_update_stats_on,        -- DBR_AUTOUPDSTATS
        sysconv(bit, d.status2 & 0x80000000) AS is_auto_update_stats_async_on,    -- DBR_AUTOUPDSTATSASYNC
        sysconv(bit, d.status2 & 0x4000) AS is_ansi_null_default_on,            -- DBR_ANSINULLDFLT
        sysconv(bit, d.status2 & 0x4000000) AS is_ansi_nulls_on,                -- DBR_ANSINULLS
        sysconv(bit, d.status2 & 0x2000) AS is_ansi_padding_on,                    -- DBR_ANSIPADDING
        sysconv(bit, d.status2 & 0x10000000) AS is_ansi_warnings_on,            -- DBR_ANSIWARNINGS
        sysconv(bit, d.status2 & 0x1000) AS is_arithabort_on,                    -- DBR_ARITHABORT
        sysconv(bit, d.status2 & 0x10000) AS is_concat_null_yields_null_on,        -- DBR_CATNULL
        sysconv(bit, d.status2 & 0x800) AS is_numeric_roundabort_on,            -- DBR_NUMEABORT
        sysconv(bit, d.status2 & 0x800000) AS is_quoted_identifier_on,            -- DBR_QUOTEDIDENT
        sysconv(bit, d.status2 & 0x20000) AS is_recursive_triggers_on,            -- DBR_RECURTRIG
        sysconv(bit, d.status2 & 0x2000000) AS is_cursor_close_on_commit_on,    -- DBR_CURSCLOSEONCOM
        sysconv(bit, d.status2 & 0x100000) AS is_local_cursor_default,            -- DBR_DEFLOCALCURS
        sysconv(bit, d.status2 & 0x20000000) AS is_fulltext_enabled,            -- DBR_FTENABLED
        sysconv(bit, d.status2 & 0x200) AS is_trustworthy_on,                -- DBR_TRUSTWORTHY
        sysconv(bit, d.status2 & 0x400) AS is_db_chaining_on,                -- DBR_DBCHAINING
        sysconv(bit, d.status2 & 0x08000000) AS is_parameterization_forced,    -- DBR_UNIVERSALAUTOPARAM
        sysconv(bit, d.status2 & 64) AS is_master_key_encrypted_by_server,    -- DBR_MASTKEY
        sysconv(bit, d.status2 & 0x00000010) AS is_query_store_on,            -- DBR_QDSENABLED
        sysconv(bit, d.category & 1) AS is_published,
        sysconv(bit, d.category & 2) AS is_subscribed,
        sysconv(bit, d.category & 4) AS is_merge_published,
        sysconv(bit, d.category & 16) AS is_distributor,
        sysconv(bit, d.category & 32) AS is_sync_with_backup,
        d.svcbrkrguid AS service_broker_guid,
        sysconv(bit, case when d.scope = 0 then 1 else 0 end) AS is_broker_enabled,
        p.log_reuse_wait, lr.name AS log_reuse_wait_desc,
        sysconv(bit, d.status2 & 4) AS is_date_correlation_on,         -- DBR_DATECORRELATIONOPT
        sysconv(bit, d.category & 64) AS is_cdc_enabled,
        sysconv(bit, d.status2 & 0x100) AS is_encrypted,                    -- DBR_ENCRYPTION
        convert(bit, d.status2 & 0x8) AS is_honor_broker_priority_on,                -- DBR_HONORBRKPRI
        sgr.guid AS replica_id,
        sgr2.guid AS group_database_id,
        ssr.indepid AS resource_pool_id,
        default_language_lcid = case when ((d.status2 & 0x80000)=0x80000 AND p.containment = 1) then convert(smallint, p.default_language) else null end,
        default_language_name = case when ((d.status2 & 0x80000)=0x80000 AND p.containment = 1) then convert(sysname, sld.name) else null end,
        default_fulltext_language_lcid = case when ((d.status2 & 0x80000)=0x80000 AND p.containment = 1) then convert(int, p.default_fulltext_language) else null end,
        default_fulltext_language_name = case when ((d.status2 & 0x80000)=0x80000 AND p.containment = 1) then convert(sysname, slft.name) else null end,
        is_nested_triggers_on = case when ((d.status2 & 0x80000)=0x80000 AND p.containment = 1) then convert(bit, p.allow_nested_triggers) else null end,
        is_transform_noise_words_on = case when ((d.status2 & 0x80000)=0x80000 AND p.containment = 1) then convert(bit, p.transform_noise_words) else null end,
        two_digit_year_cutoff = case when ((d.status2 & 0x80000)=0x80000 AND p.containment = 1) then convert(smallint, p.two_digit_year_cutoff) else null end,
        containment = sysconv(tinyint, (d.status2 & 0x80000)/0x80000), -- DBR_IS_CDB
        containment_desc = convert(nvarchar(60), cdb.name),
        p.recovery_seconds AS target_recovery_time_in_seconds,
        p.delayed_durability,
        case when (p.delayed_durability = 0) then CAST('DISABLED' AS nvarchar(60)) -- LCOPT_DISABLED
             when (p.delayed_durability = 1) then CAST('ALLOWED' AS nvarchar(60)) -- LCOPT_ALLOWED
             when (p.delayed_durability = 2) then CAST('FORCED' AS nvarchar(60)) -- LCOPT_FORCED
             else NULL
             end AS delayed_durability_desc,
        convert(bit, d.status2 & 0x80) AS is_memory_optimized_elevate_to_snapshot_on                -- DBR_HKELEVATETOSNAPSHOT
    FROM sys.sysdbreg d OUTER APPLY OpenRowset(TABLE DBPROP, (case when serverproperty('EngineEdition') = 5 then DB_ID() else d.id end)) p
    LEFT JOIN sys.syssingleobjrefs r ON r.depid = d.id AND r.class = 96 AND r.depsubid = 0    -- SRC_VIEWPOINTDB
    LEFT JOIN sys.syspalvalues st ON st.class = 'DBST' AND st.value = p.state
    LEFT JOIN sys.syspalvalues ua ON ua.class = 'DBUA' AND ua.value = p.user_access
    LEFT JOIN sys.syspalvalues si ON si.class = 'DBSI' AND si.value = p.snapshot_isolation_state
    LEFT JOIN sys.syspalvalues ro ON ro.class = 'DBRO' AND ro.value = p.recovery_model
    LEFT JOIN sys.syspalvalues pv ON pv.class = 'DBPV' AND pv.value = p.page_verify_option
    LEFT JOIN sys.syspalvalues lr ON lr.class = 'LRWT' AND lr.value = p.log_reuse_wait
    LEFT JOIN sys.syssingleobjrefs agdb ON agdb.depid = d.id AND agdb.class = 104 AND agdb.depsubid = 0    -- SRC_AVAILABILITYGROUP 
    LEFT JOIN master.sys.syssingleobjrefs ssr ON ssr.class = 108 AND ssr.depid = d.id -- SRC_RG_DB_TO_POOL
    LEFT JOIN master.sys.sysclsobjs  ag ON ag.id = agdb.indepid AND ag.class = 67 -- SOC_AVAILABILITY_GROUP
    LEFT JOIN master.sys.sysguidrefs sgr ON sgr.class = 8 AND sgr.id = ag.id AND sgr.subid = 1 -- GRC_AGGUID / AGGUID_REPLICA_ID
    LEFT JOIN master.sys.sysguidrefs sgr2 ON sgr2.class = 9 AND sgr2.id = ag.id AND sgr2.subid = d.id -- GRC_AGDBGUID
    LEFT JOIN sys.syspalvalues cdb ON cdb.class = 'DCDB' AND cdb.value = CASE WHEN (d.status2 & 0x80000)=0x80000 THEN 1 ELSE 0 END
    LEFT JOIN sys.syslanguages sld ON sld.lcid = p.default_language
    LEFT JOIN sys.fulltext_languages slft ON slft.lcid = p.default_fulltext_language
    LEFT JOIN sys.sysobjvalues coll ON coll.valclass = 102 AND coll.subobjid = 0 AND coll.objid = d.id    -- SVC_DATACOLLATION
    WHERE d.id < 0x7fff
        AND has_access('DB', (case when serverproperty('EngineEdition') = 5 then DB_ID() else d.id end)) = 1
 
GO

 

 

 

 

 

 

EngineEdition

服务器上安装的 数据库引擎 实例的 SQL Server版本。

1 = Personal 或 Desktop Engine(不适用于 SQL Server 2005?和更高版本。)

2 = Standard(对 Standard、Web 和 Business Intelligence 返回该值。)

3 = Enterprise(对 Enterprise、Developer 以及两个 Enterprise 版本返回该值。)

4 = Express(对 Express、Express with Tools 和 Express with Advanced Services 返回该值)

5 = SQL Database

6 = SQL 数据仓库

8 = 托管实例

基本数据类型:int

 

 

 

因为当前数据库版本为标准版,所以stated的值来自OpenRowset(TABLE DBPROP, (case when serverproperty('EngineEdition') = 5 then DB_ID() else d.id end)) p

 

我们可以在单用户专用连接服务器模式下查看相关记录的值。如下截图所示:

 

 

clip_image003

 

 

clip_image004

 

 

其实发现这个问题(其实我更愿意称其为一个bug)是一次查询时的意外发现。实验测试让我有点吃惊。居然这么多版本都是这种情况! 这到底是一个bug还是数据库什么内部机制呢?