曾经想实现Log Explorer for SQL Server的功能，利用ldf里面的日志来还原误删除的数据
这里有一篇文章做到了，不过似乎不是所有的数据类型都支持
以下为译文：http://raresql.com/2011/10/22/how-to-recover-deleted-data-from-sql-sever/
在我使用SQLSERVER的这些年里面，大部分人都会问我一个问题：“能不能恢复被删除的数据？？”
现在，从SQLSERVER2005 或以上版本能很容易能够恢复被删除的数据
（注意：这个脚本能恢复下面的数据类型的数据 而且兼容CS 排序规则）
- image
- text
- uniqueidentifier
- tinyint
- smallint
- int
- smalldatetime
- real
- money
- datetime
- float
- sql_variant
- ntext
- bit
- decimal
- numeric
- smallmoney
- bigint
- varbinary
- varchar
- binary
- char
- timestamp
- nvarchar
- nchar
- xml
- sysname
让我来用demo来解释一下我是怎么做到的
USE master
GO--创建数据库CREATEDATABASE test
GOUSE[test]GO--创建表CREATETABLE[dbo].[aa](
[id][int]IDENTITY(1,1) NOTNULL,
[NAME][nvarchar](200) NULL
) ON[PRIMARY]GO--插入测试数据INSERT[dbo].[aa]
( [NAME] )
SELECT‘你好‘GO--删除数据Deletefrom aa
Go--验证数据是否已经删除Select*from aa
Go
现在你需要创建一个存储过程来恢复你的数据
-- Script Name: Recover_Deleted_Data_Proc
-- Script Type : Recovery Procedure
-- Develop By: Muhammad Imran
-- Date Created: 15 Oct 2011
-- Modify Date: 22 Aug 2012
-- Version : 3.1
-- Notes : Included BLOB data types for recovery.& Compatibile with Default , CS collation , Arabic_CI_AS.CREATEPROCEDURE Recover_Deleted_Data_Proc
@Database_NameNVARCHAR(MAX) ,
@SchemaName_n_TableNameNVARCHAR(MAX) ,
@Date_FromDATETIME=‘1900/01/01‘ ,
@Date_ToDATETIME=‘9999/12/31‘[email protected](8000)
[email protected](MAX)
[email protected]@AllocUnitNameNVARCHAR(MAX)
[email protected](MAX)
[email protected][email protected]_Level= dtb.compatibility_level
FROM master.sys.databases AS dtb
WHERE dtb.name [email protected]_NameIFISNULL(@Compatibility_Level, 0) <=80BEGINRAISERROR(‘The compatibility level should be equal to or greater SQL SERVER 2005 (90)‘,16,1)
RETURNENDIF ( SELECTCOUNT(*)
FROM INFORMATION_SCHEMA.TABLES
WHERE[TABLE_SCHEMA]+‘.‘+[TABLE_NAME][email protected]_n_TableName
) =0BEGINRAISERROR(‘Could not found the table in the defined database‘,16,1)
[email protected]
(
[ID]INT ,
[Bitvalue]INT
)
--Create table to set the bit position of one [email protected] ,
2UNIONALLSELECT1 ,
2UNIONALLSELECT2 ,
4UNIONALLSELECT3 ,
8UNIONALLSELECT4 ,
16UNIONALLSELECT5 ,
32UNIONALLSELECT6 ,
64UNIONALLSELECT7 ,
128--Create table to collect the row [email protected]
(
[Row ID]INTIDENTITY(1, 1) ,
[RowLogContents]VARBINARY(8000) ,
[AllocUnitID]BIGINT ,
[Transaction ID]NVARCHAR(MAX) ,
[FixedLengthData]SMALLINT ,
[TotalNoOfCols]SMALLINT ,
[NullBitMapLength]SMALLINT ,
[NullBytes]VARBINARY(8000) ,
[TotalNoofVarCols]SMALLINT ,
[ColumnOffsetArray]VARBINARY(8000) ,
[VarColumnStart]SMALLINT ,
[Slot ID]INT ,
[NullBitMap]VARCHAR(MAX)
)
--Create a common table expression to get all the row data plus how many bytes we have for each row.;
WITH RowData
AS ( SELECT[RowLog Contents 0]AS[RowLogContents] ,
[AllocUnitID]AS[AllocUnitID] ,
[Transaction ID]AS[Transaction ID]--[Fixed Length Data] = Substring (RowLog content 0, Status Bit A+ Status Bit B + 1,2 bytes) ,
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) AS[FixedLengthData][email protected] [TotalnoOfCols] = Substring (RowLog content 0, [Fixed Length Data] + 1,2 bytes) ,
CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +1,
2)))) AS[TotalNoOfCols]--[NullBitMapLength]=ceiling([Total No of Columns] /8.0) ,
CONVERT(INT, CEILING(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +1,
2)))) /8.0)) AS[NullBitMapLength]--[Null Bytes] = Substring (RowLog content 0, Status Bit A+ Status Bit B + [Fixed Length Data] +1, [NullBitMapLength] ) ,
SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +3,
CONVERT(INT, CEILING(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +1,
2)))) /8.0))) AS[NullBytes]--[TotalNoofVarCols] = Substring (RowLog content 0, Status Bit A+ Status Bit B + [Fixed Length Data] +1, [Null Bitmap length] + 2 ) ,
( CASEWHENSUBSTRING([RowLog Contents 0], 1, 1) IN (
0x10, 0x30, 0x70 )
THENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +3+CONVERT(INT, CEILING(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +1,
2)))) /8.0)), 2))))
ELSENULLEND ) AS[TotalNoofVarCols]--[ColumnOffsetArray]= Substring (RowLog content 0, Status Bit A+ Status Bit B + [Fixed Length Data] +1, [Null Bitmap length] + 2 , [TotalNoofVarCols]*2 ) ,
( CASEWHENSUBSTRING([RowLog Contents 0], 1, 1) IN (
0x10, 0x30, 0x70 )
THENSUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +3+CONVERT(INT, CEILING(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +1,
2)))) /8.0))
+2,
( CASEWHENSUBSTRING([RowLog Contents 0],
1, 1) IN ( 0x10,
0x30, 0x70 )
THENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +3+CONVERT(INT, CEILING(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +1,
2)))) /8.0)), 2))))
ELSENULLEND ) *2)
ELSENULLEND ) AS[ColumnOffsetArray]-- Variable column Start = Status Bit A+ Status Bit B + [Fixed Length Data] + [Null Bitmap length] + 2+([TotalNoofVarCols]*2) ,
CASEWHENSUBSTRING([RowLog Contents 0], 1, 1) IN (
0x10, 0x30, 0x70 )
THEN ( CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +4+CONVERT(INT, CEILING(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +1,
2)))) /8.0))
+ ( ( CASEWHENSUBSTRING([RowLog Contents 0],
1, 1) IN ( 0x10,
0x30, 0x70 )
THENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +3+CONVERT(INT, CEILING(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(SUBSTRING([RowLog Contents 0],
2+1, 2)))) +1,
2)))) /8.0)), 2))))
ELSENULLEND ) *2 ) )
ELSENULLENDAS[VarColumnStart] ,
[Slot ID]FROM sys.fn_dblog(NULL, NULL)
WHERE AllocUnitId IN (
SELECT[Allocation_unit_id]FROM sys.allocation_units allocunits
INNERJOIN sys.partitions partitions ON ( allocunits.type IN (
1, 3 )
AND partitions.hobt_id = allocunits.container_id
)
OR ( allocunits.type =2AND partitions.partition_id = allocunits.container_id
)
WHEREobject_id=OBJECT_ID(‘‘[email protected]_n_TableName+‘‘) )
AND Context IN ( ‘LCX_MARK_AS_GHOST‘, ‘LCX_HEAP‘ )
AND Operation IN ( ‘LOP_DELETE_ROWS‘ )
ANDSUBSTRING([RowLog Contents 0], 1, 1) IN ( 0x10,
0x30, 0x70 )
/*Use this subquery to filter the date*/AND[TRANSACTION ID]IN (
SELECTDISTINCT[TRANSACTION ID]FROM sys.fn_dblog(NULL, NULL)
WHERE Context IN ( ‘LCX_NULL‘ )
AND Operation IN ( ‘LOP_BEGIN_XACT‘ )
AND[Transaction Name]IN ( ‘DELETE‘,
‘user_transaction‘ )
ANDCONVERT(NVARCHAR(11), [Begin Time]) [email protected][email protected]_To )
),
--Use this technique to repeate the row till the no of bytes of the row. N1 ( n )
AS ( SELECT1UNIONALLSELECT1
),
N2 ( n )
AS ( SELECT1FROM N1 AS X ,
N1 AS Y
),
N3 ( n )
AS ( SELECT1FROM N2 AS X ,
N2 AS Y
),
N4 ( n )
AS ( SELECT ROW_NUMBER() OVER ( ORDERBY X.n )
FROM N3 AS X ,
N3 AS Y
)
[email protected] RowLogContents ,
[AllocUnitID] ,
[Transaction ID] ,
[FixedLengthData] ,
[TotalNoOfCols] ,
[NullBitMapLength] ,
[NullBytes] ,
[TotalNoofVarCols] ,
[ColumnOffsetArray] ,
[VarColumnStart] ,
[Slot ID]---Get the Null value against each column (1 means null zero means not null) ,
[NullBitMap]= ( REPLACE(STUFF(( SELECT‘,‘+ ( CASEWHEN[ID]=0THENCONVERT(NVARCHAR(1), ( SUBSTRING(NullBytes,
n, 1) %2 ))
ELSECONVERT(NVARCHAR(1), ( ( SUBSTRING(NullBytes,
n, 1)
/[Bitvalue] )
%2 ))
END ) --as [nullBitMap]FROM N4 AS Nums
JOIN RowData AS C ON n <= NullBitMapLength
[email protected]
C.[RowLogContents]= D.[RowLogContents]ORDERBY[RowLogContents] ,
n ASCFOR
XML PATH(‘‘)
), 1, 1, ‘‘), ‘,‘, ‘‘) )
FROM RowData D
IF ( SELECTCOUNT(*)
[email protected]
) =0BEGINRAISERROR(‘There is no data in the log as per the search criteria‘,16,1)
[email protected]
(
[Row ID]INT ,
[Rowlogcontents]VARBINARY(MAX) ,
[NAME] SYSNAME ,
[nullbit]SMALLINT ,
[leaf_offset]SMALLINT ,
[length]SMALLINT ,
[system_type_id]TINYINT ,
[bitpos]TINYINT ,
[xprec]TINYINT ,
[xscale]TINYINT ,
[is_null]INT ,
[Column value Size]INT ,
[Column Length]INT ,
[hex_Value]VARBINARY(MAX) ,
[Slot ID]INT ,
[Update]INT
)
--Create common table expression and join it with the rowdata table
-- to get each column details
/*This part is for variable data columns*/[email protected],
--(col.columnOffValue - col.columnLength) + 1,
--col.columnLength
--)[email protected][Row ID] ,
Rowlogcontents ,
NAME ,
cols.leaf_null_bit AS nullbit ,
leaf_offset ,
ISNULL(syscolumns.length, cols.max_length) AS[length] ,
cols.system_type_id ,
cols.leaf_bit_position AS bitpos ,
ISNULL(syscolumns.xprec, cols.precision) AS xprec ,
ISNULL(syscolumns.xscale, cols.scale) AS xscale ,
SUBSTRING([nullBitMap], cols.leaf_null_bit, 1) AS is_null ,
( CASEWHEN leaf_offset <1ANDSUBSTRING([nullBitMap], cols.leaf_null_bit,
1) =0THEN ( CASEWHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) >30000THENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
-POWER(2, 15)
ELSECONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
END )
END ) AS[Column value Size] ,
( CASEWHEN leaf_offset <1ANDSUBSTRING([nullBitMap], cols.leaf_null_bit,
1) =0THEN ( CASEWHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) >30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) <30000THEN ( CASEWHEN[System_type_id]IN (
35, 34, 99 ) THEN16ELSE24END )
WHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) >30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) >30000THEN ( CASEWHEN[System_type_id]IN (
35, 34, 99 ) THEN16ELSE24END ) --24 WHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) <30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) <30000THEN ( CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
-ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) )
WHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) <30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) >30000THENPOWER(2, 15)
+CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
-ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart])
END )
END ) AS[Column Length] ,
( CASEWHENSUBSTRING([nullBitMap], cols.leaf_null_bit, 1) =1THENNULLELSESUBSTRING(Rowlogcontents,
( ( CASEWHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) >30000THENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
-POWER(2, 15)
ELSECONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
END )
- ( CASEWHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) >30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) <30000THEN ( CASEWHEN[System_type_id]IN (
35, 34, 99 )
THEN16ELSE24END ) --24 WHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) >30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) >30000THEN ( CASEWHEN[System_type_id]IN (
35, 34, 99 )
THEN16ELSE24END ) --24 WHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) <30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) <30000THENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
-ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart])
WHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) <30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) >30000THENPOWER(2, 15)
+CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
-ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart])
END ) ) +1,
( CASEWHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) >30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) <30000THEN ( CASEWHEN[System_type_id]IN (
35, 34, 99 )
THEN16ELSE24END ) --24 WHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) >30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) >30000THEN ( CASEWHEN[System_type_id]IN (
35, 34, 99 )
THEN16ELSE24END ) --24 WHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) <30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) <30000THENABS(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
-ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]))
WHENCONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2)))) <30000ANDISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart]) >30000THENPOWER(2, 15)
+CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* leaf_offset
*-1 ) -1, 2))))
-ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE(SUBSTRING([ColumnOffsetArray],
( 2* ( ( leaf_offset
*-1 ) -1 ) )
-1, 2)))), 0),
[varColumnStart])
END ))
END ) AS hex_Value ,
[Slot ID] ,
[email protected] A
INNERJOIN sys.allocation_units allocunits ON A.[AllocUnitId]= allocunits.[Allocation_Unit_Id]INNERJOIN sys.partitions partitions ON ( allocunits.type IN (
1, 3 )
AND partitions.hobt_id = allocunits.container_id
)
OR ( allocunits.type =2AND partitions.partition_id = allocunits.container_id
)
INNERJOIN sys.system_internals_partition_columns cols ON cols.partition_id = partitions.partition_id
LEFTOUTERJOIN syscolumns ON syscolumns.id = partitions.object_idAND syscolumns.colid = cols.partition_column_id
WHERE leaf_offset <0UNION/*This part is for fixed data columns*/SELECT[Row ID] ,
Rowlogcontents ,
NAME ,
cols.leaf_null_bit AS nullbit ,
leaf_offset ,
ISNULL(syscolumns.length, cols.max_length) AS[length] ,
cols.system_type_id ,
cols.leaf_bit_position AS bitpos ,
ISNULL(syscolumns.xprec, cols.precision) AS xprec ,
ISNULL(syscolumns.xscale, cols.scale) AS xscale ,
SUBSTRING([nullBitMap], cols.leaf_null_bit, 1) AS is_null ,
( SELECTTOP1ISNULL(SUM(CASEWHEN C.leaf_offset >1THEN max_length
ELSE0END), 0)
FROM sys.system_internals_partition_columns C
WHERE cols.partition_id = C.partition_id
AND C.leaf_null_bit < cols.leaf_null_bit
) +5AS[Column value Size] ,
syscolumns.length AS[Column Length] ,
CASEWHENSUBSTRING([nullBitMap], cols.leaf_null_bit, 1) =1THENNULLELSESUBSTRING(Rowlogcontents,
( SELECTTOP1ISNULL(SUM(CASEWHEN C.leaf_offset >1AND C.leaf_bit_position =0THEN max_length
ELSE0END), 0)
FROM sys.system_internals_partition_columns C
WHERE cols.partition_id = C.partition_id
AND C.leaf_null_bit < cols.leaf_null_bit
) +5, syscolumns.length)
ENDAS hex_Value ,
[Slot ID] ,
[email protected] A
INNERJOIN sys.allocation_units allocunits ON A.[AllocUnitId]= allocunits.[Allocation_Unit_Id]INNERJOIN sys.partitions partitions ON ( allocunits.type IN (
1, 3 )
AND partitions.hobt_id = allocunits.container_id
)
OR ( allocunits.type =2AND partitions.partition_id = allocunits.container_id
)
INNERJOIN sys.system_internals_partition_columns cols ON cols.partition_id = partitions.partition_id
LEFTOUTERJOIN syscolumns ON syscolumns.id = partitions.object_idAND syscolumns.colid = cols.partition_column_id
WHERE leaf_offset >0ORDERBY nullbit
[email protected]@BitColumnByte=CONVERT(INT, CEILING(COUNT(*) /8.0))
[email protected][System_Type_id]=104;
WITH N1 ( n )
AS ( SELECT1UNIONALLSELECT1
),
N2 ( n )
AS ( SELECT1FROM N1 AS X ,
N1 AS Y
),
N3 ( n )
AS ( SELECT1FROM N2 AS X ,
N2 AS Y
),
N4 ( n )
AS ( SELECT ROW_NUMBER() OVER ( ORDERBY X.n )
FROM N3 AS X ,
N3 AS Y
),
CTE
AS ( SELECT RowLogContents ,
[nullbit] ,
[BitMap]=CONVERT(VARBINARY(1), CONVERT(INT, SUBSTRING(( REPLACE(STUFF(( SELECT‘,‘+ ( CASEWHEN[ID]=0THENCONVERT(NVARCHAR(1), ( SUBSTRING(hex_Value,
n, 1) %2 ))
ELSECONVERT(NVARCHAR(1), ( ( SUBSTRING(hex_Value,
n, 1)
/[Bitvalue] )
%2 ))
END ) --as [nullBitMap]FROM
N4 AS Nums
[email protected] C ON n <[email protected][System_Type_id]=104AND bitpos [email protected]
C.[RowLogContents]= D.[RowLogContents]ORDERBY[RowLogContents] ,
n ASCFOR
XML
PATH(‘‘)
), 1, 1, ‘‘),
‘,‘, ‘‘) ),
bitpos +1, 1)))
[email protected] D
WHERE[System_Type_id]=104
)
UPDATE A
SET[hex_Value]=[BitMap][email protected] A
INNERJOIN CTE B ON A.[RowLogContents]= B.[RowLogContents]AND A.[nullbit]= B.[nullbit]/**************Check for BLOB DATA TYPES******************************/[email protected]@[email protected]@[email protected]@ContextVARCHAR(50)
[email protected](MAX)
[email protected]_TEXT_MIXVARBINARY(MAX)
[email protected]
(
[ParentObject] SYSNAME ,
[Object] SYSNAME ,
[Field] SYSNAME ,
[Value] SYSNAME
)
[email protected]
(
[Page ID] SYSNAME ,
[File IDS]INT ,
[Page IDS]INT ,
[AllocUnitId]BIGINT ,
[ParentObject] SYSNAME ,
[Object] SYSNAME ,
[Field] SYSNAME ,
[Value] SYSNAME
)
[email protected]
(
[ID]INTIDENTITY(1, 1) ,
[PAGE ID]VARCHAR(MAX) ,
[FILE IDS]INT ,
[PAGE IDS]INT ,
[Slot ID]INT ,
[AllocUnitId]BIGINT ,
[RowLog Contents 0_var]VARCHAR(MAX) ,
[RowLog Length]VARCHAR(50) ,
[RowLog Len]INT ,
[RowLog Contents 0]VARBINARY(MAX) ,
[Link ID]INTDEFAULT ( 0 ) ,
[Update]INT
)
DECLARE Page_Data_Cursor CURSORFOR/*We need to filter LOP_MODIFY_ROW,LOP_MODIFY_COLUMNS from log for deleted records of BLOB data type& Get its Slot No, Page ID & AllocUnit ID*/SELECTLTRIM(RTRIM(REPLACE([Description], ‘Deallocated‘, ‘‘))) AS[PAGE ID] ,
[Slot ID] ,
[AllocUnitId] ,
NULLAS[RowLog Contents 0] ,
NULLAS[RowLog Contents 0] ,
Context
FROM sys.fn_dblog(NULL, NULL)
WHERE AllocUnitId IN (
SELECT[Allocation_unit_id]FROM sys.allocation_units allocunits
INNERJOIN sys.partitions partitions ON ( allocunits.type IN (
1, 3 )
AND partitions.hobt_id = allocunits.container_id
)
OR ( allocunits.type =2AND partitions.partition_id = allocunits.container_id
)
WHEREobject_id=OBJECT_ID(‘‘[email protected]_n_TableName+‘‘) )
AND Operation IN ( ‘LOP_MODIFY_ROW‘ )
AND[Context]IN ( ‘LCX_PFS‘ )
AND Description LIKE‘%Deallocated%‘/*Use this subquery to filter the date*/AND[TRANSACTION ID]IN (
SELECTDISTINCT[TRANSACTION ID]FROM sys.fn_dblog(NULL, NULL)
WHERE Context IN ( ‘LCX_NULL‘ )
AND Operation IN ( ‘LOP_BEGIN_XACT‘ )
AND[Transaction Name]=‘DELETE‘ANDCONVERT(NVARCHAR(11), [Begin Time]) [email protected][email protected]_To )
GROUPBY[Description] ,
[Slot ID] ,
[AllocUnitId] ,
Context
UNIONSELECT[PAGE ID] ,
[Slot ID] ,
[AllocUnitId] ,
SUBSTRING([RowLog Contents 0], 15,
LEN([RowLog Contents 0])) AS[RowLog Contents 0] ,
CONVERT(INT, SUBSTRING([RowLog Contents 0], 7, 2)) ,
Context --,CAST(RIGHT([Current LSN],4) AS INT) AS [Current LSN]FROM sys.fn_dblog(NULL, NULL)
WHERE AllocUnitId IN (
SELECT[Allocation_unit_id]FROM sys.allocation_units allocunits
INNERJOIN sys.partitions partitions ON ( allocunits.type IN (
1, 3 )
AND partitions.hobt_id = allocunits.container_id
)
OR ( allocunits.type =2AND partitions.partition_id = allocunits.container_id
)
WHEREobject_id=OBJECT_ID(‘‘[email protected]_n_TableName+‘‘) )
AND Context IN ( ‘LCX_TEXT_MIX‘ )
AND Operation IN ( ‘LOP_DELETE_ROWS‘ )
/*Use this subquery to filter the date*/AND[TRANSACTION ID]IN (
SELECTDISTINCT[TRANSACTION ID]FROM sys.fn_dblog(NULL, NULL)
WHERE Context IN ( ‘LCX_NULL‘ )
AND Operation IN ( ‘LOP_BEGIN_XACT‘ )
AND[Transaction Name]=‘DELETE‘ANDCONVERT(NVARCHAR(11), [Begin Time]) [email protected][email protected]_To )
/****************************************/OPEN Page_Data_Cursor
FETCHNEXTFROM Page_Data_Cursor [email protected], @Slotid,
@AllocUnitID, @LCX_TEXT_MIX, @LinkID, @[email protected]@[email protected]_pageidASVARCHAR(MAX)
/*Page ID contains File Number and page number It looks like 0001:00000130.
In this example 0001 is file Number & 00000130 is Page Number & These numbers are in Hex format*/[email protected]=SUBSTRING(@ConsolidatedPageID, 0,
CHARINDEX(‘:‘, @ConsolidatedPageID)) -- Seperate File ID from Page [email protected]_pageid=‘0x‘+SUBSTRING(@ConsolidatedPageID,
CHARINDEX(‘:‘,
@ConsolidatedPageID)
+1, LEN(@ConsolidatedPageID)) ---Seperate the page [email protected]=CONVERT(INT, CAST(‘‘AS XML).value(‘xs:hexBinary(substring(sql:variable("@hex_pageid"),sql:column("t.pos")) )‘,
‘varbinary(max)‘)) -- Convert Page ID from hex to integerFROM ( SELECTCASESUBSTRING(@hex_pageid, 1, 2)
WHEN‘0x‘THEN3ELSE0END
) AS t ( pos )
[email protected]=‘LCX_PFS‘[email protected]@temppagedataEXEC
( ‘DBCC PAGE(‘[email protected]_Name+‘, ‘[email protected]+‘, ‘[email protected]+‘, 1) with tableresults,no_infomsgs;‘
);
[email protected]@ConsolidatedPageID ,
@fileid ,
@pageid ,
@AllocUnitID ,
[ParentObject] ,
[Object] ,
[Field] ,
[Value][email protected]@Context=‘LCX_TEXT_MIX‘[email protected]@ConsolidatedPageID ,
@fileid ,
@pageid ,
@Slotid ,
@AllocUnitID ,
NULL ,
0 ,
CONVERT(INT, CONVERT(VARBINARY, REVERSE(SUBSTRING(@LCX_TEXT_MIX,
11, 2)))) ,
@LCX_TEXT_MIX ,
@LinkID ,
0ENDFETCHNEXTFROM Page_Data_Cursor [email protected], @Slotid,
@AllocUnitID, @LCX_TEXT_MIX, @LinkID, @ContextENDCLOSE Page_Data_Cursor
DEALLOCATE Page_Data_Cursor
[email protected](MAX);
--The data is in multiple rows in the page, so we need to convert it into one row as a single hex value.--This hex value is in string [email protected]
( [PAGE ID] ,
[FILE IDS] ,
[PAGE IDS] ,
[Slot ID] ,
[AllocUnitId] ,
[RowLog Contents 0_var] ,
[RowLog Length]
)
SELECT[Page ID] ,
[FILE IDS] ,
[PAGE IDS] ,
SUBSTRING([ParentObject],
CHARINDEX(‘Slot‘, [ParentObject]) +4,
( CHARINDEX(‘Offset‘, [ParentObject])
- ( CHARINDEX(‘Slot‘, [ParentObject]) +4 ) )
-2) AS[Slot ID] ,
[AllocUnitId] ,
SUBSTRING(( SELECTREPLACE(STUFF(( SELECTREPLACE(SUBSTRING([Value],
CHARINDEX(‘:‘,
[Value]) +1,
CHARINDEX(‘†‘,
[Value])
-CHARINDEX(‘:‘,
[Value])), ‘†‘,
‘‘)
[email protected] C
WHERE B.[Page ID]= C.[Page ID]ANDSUBSTRING(B.[ParentObject],
CHARINDEX(‘Slot‘,
B.[ParentObject])
+4,
( CHARINDEX(‘Offset‘,
B.[ParentObject])
- ( CHARINDEX(‘Slot‘,
B.[ParentObject])
+4 ) )) =SUBSTRING(C.[ParentObject],
CHARINDEX(‘Slot‘,
C.[ParentObject])
+4,
( CHARINDEX(‘Offset‘,
C.[ParentObject])
- ( CHARINDEX(‘Slot‘,
C.[ParentObject])
+4 ) ))
AND[Object]LIKE‘%Memory Dump%‘ORDERBY‘0x‘+LEFT([Value],
CHARINDEX(‘:‘,
[Value]) -1)
FOR
XML PATH(‘‘)
), 1, 1, ‘‘), ‘‘, ‘‘)
), 1, 20000) AS[Value] ,
SUBSTRING(( SELECT‘0x‘+REPLACE(STUFF(( SELECTREPLACE(SUBSTRING([Value],
CHARINDEX(‘:‘,
[Value]) +1,
CHARINDEX(‘†‘,
[Value])
-CHARINDEX(‘:‘,
[Value])), ‘†‘,
‘‘)
[email protected] C
WHERE
B.[Page ID]= C.[Page ID]ANDSUBSTRING(B.[ParentObject],
CHARINDEX(‘Slot‘,
B.[ParentObject])
+4,
( CHARINDEX(‘Offset‘,
B.[ParentObject])
- ( CHARINDEX(‘Slot‘,
B.[ParentObject])
+4 ) )) =SUBSTRING(C.[ParentObject],
CHARINDEX(‘Slot‘,
C.[ParentObject])
+4,
( CHARINDEX(‘Offset‘,
C.[ParentObject])
- ( CHARINDEX(‘Slot‘,
C.[ParentObject])
+4 ) ))
AND[Object]LIKE‘%Memory Dump%‘ORDERBY‘0x‘+LEFT([Value],
CHARINDEX(‘:‘,
[Value]) -1)
FOR
XML PATH(‘‘)
), 1, 1, ‘‘), ‘‘, ‘‘)
), 7, 4) AS[Length][email protected] B
WHERE[Object]LIKE‘%Memory Dump%‘GROUPBY[Page ID] ,
[FILE IDS] ,
[PAGE IDS] ,
[ParentObject] ,
[AllocUnitId]--,[Current LSN]ORDERBY[Slot ID][email protected][RowLog Len]=CONVERT(VARBINARY(8000), REVERSE(CAST(‘‘AS XML).value(‘xs:hexBinary(substring(sql:column("[RowLog Length]"),0))‘,
‘varbinary(Max)‘)))
[email protected][LINK ID][email protected][RowLog Contents 0]=CAST(‘‘AS XML).value(‘xs:hexBinary(substring(sql:column("[RowLog Contents 0_var]"),0))‘,
‘varbinary(Max)‘)
[email protected][LINK ID]=0UPDATE B
SET B.[RowLog Contents 0]= ( CASEWHEN A.[RowLog Contents 0]ISNOTNULLAND C.[RowLog Contents 0]ISNOTNULLTHEN A.[RowLog Contents 0]+ C.[RowLog Contents 0]WHEN A.[RowLog Contents 0]ISNULLAND C.[RowLog Contents 0]ISNOTNULLTHEN C.[RowLog Contents 0]WHEN A.[RowLog Contents 0]ISNOTNULLAND C.[RowLog Contents 0]ISNULLTHEN A.[RowLog Contents 0]END ) ,
B.[Update]=ISNULL(B.[Update], 0) [email protected] B
[email protected] A ON A.[Page IDS]=CONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING(B.[RowLog Contents 0],
15+14, 2))))
AND A.[File IDS]=CONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING(B.[RowLog Contents 0],
19+14, 2))))
AND A.[Link ID]= B.[Link ID][email protected] C ON C.[Page IDS]=CONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING(B.[RowLog Contents 0],
27+14, 2))))
AND C.[File IDS]=CONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING(B.[RowLog Contents 0],
31+14, 2))))
AND C.[Link ID]= B.[Link ID]WHERE ( A.[RowLog Contents 0]ISNOTNULLOR C.[RowLog Contents 0]ISNOTNULL
)
UPDATE B
SET B.[RowLog Contents 0]= ( CASEWHEN A.[RowLog Contents 0]ISNOTNULLAND C.[RowLog Contents 0]ISNOTNULLTHEN A.[RowLog Contents 0]+ C.[RowLog Contents 0]WHEN A.[RowLog Contents 0]ISNULLAND C.[RowLog Contents 0]ISNOTNULLTHEN C.[RowLog Contents 0]WHEN A.[RowLog Contents 0]ISNOTNULLAND C.[RowLog Contents 0]ISNULLTHEN A.[RowLog Contents 0]END )
--,B.[Update]=ISNULL(B.[Update],0)[email protected] B
[email protected] A ON A.[Page IDS]=CONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING(B.[RowLog Contents 0],
15+14, 2))))
AND A.[File IDS]=CONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING(B.[RowLog Contents 0],
19+14, 2))))
AND A.[Link ID]<> B.[Link ID]AND B.[Update][email protected] C ON C.[Page IDS]=CONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING(B.[RowLog Contents 0],
27+14, 2))))
AND C.[File IDS]=CONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING(B.[RowLog Contents 0],
31+14, 2))))
AND C.[Link ID]<> B.[Link ID]AND B.[Update]=0WHERE ( A.[RowLog Contents 0]ISNOTNULLOR C.[RowLog Contents 0]ISNOTNULL
)
[email protected][RowLog Contents 0]= ( CASEWHEN[RowLog Len]>=8000THENSUBSTRING([RowLog Contents 0],
15, [RowLog Len])
WHEN[RowLog Len]<8000THENSUBSTRING([RowLog Contents 0],
15+6,
CONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING([RowLog Contents 0],
15, 6)))))
END )
[email protected][LINK ID][email protected][hex_Value]=[RowLog Contents 0]--,A.[Update]=A.[Update][email protected] A
[email protected] B ONCONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING([hex_value],
17, 4)))) =[PAGE IDS]ANDCONVERT(INT, SUBSTRING([hex_value],
9, 2)) = B.[Link ID]WHERE[System_Type_Id]IN ( 99, 167, 175, 231, 239, 241, 165, 98 )
AND[Link ID]<>[email protected][hex_Value]= ( CASEWHEN B.[RowLog Contents 0]ISNOTNULLAND C.[RowLog Contents 0]ISNOTNULLTHEN B.[RowLog Contents 0]+ C.[RowLog Contents 0]WHEN B.[RowLog Contents 0]ISNULLAND C.[RowLog Contents 0]ISNOTNULLTHEN C.[RowLog Contents 0]WHEN B.[RowLog Contents 0]ISNOTNULLAND C.[RowLog Contents 0]ISNULLTHEN B.[RowLog Contents 0]END )
--,A.[Update]=A.[Update][email protected] A
[email protected] B ONCONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING([hex_value],
5, 4)))) = B.[PAGE IDS]AND B.[Link ID][email protected] C ONCONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING([hex_value],
17, 4)))) = C.[PAGE IDS]AND C.[Link ID]=0WHERE[System_Type_Id]IN ( 99, 167, 175, 231, 239, 241, 165, 98 )
AND ( B.[RowLog Contents 0]ISNOTNULLOR C.[RowLog Contents 0]ISNOTNULL
)
[email protected][hex_Value]=[RowLog Contents 0]--,A.[Update]=A.[Update][email protected] A
[email protected] B ONCONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING([hex_value],
9, 4)))) =[PAGE IDS]ANDCONVERT(INT, SUBSTRING([hex_value],
3, 2)) =[Link ID]WHERE[System_Type_Id]IN ( 35, 34, 99 )
AND[Link ID]<>[email protected][hex_Value]=[RowLog Contents 0]--,A.[Update]=A.[Update][email protected] A
[email protected] B ONCONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING([hex_value],
9, 4)))) =[PAGE IDS]WHERE[System_Type_Id]IN ( 35, 34, 99 )
AND[Link ID][email protected][hex_Value]=[RowLog Contents 0]--,A.[Update]=A.[Update][email protected] A
[email protected] B ONCONVERT(INT, CONVERT(VARBINARY(MAX), REVERSE(SUBSTRING([hex_value],
15, 4)))) =[PAGE IDS]WHERE[System_Type_Id]IN ( 35, 34, 99 )
AND[Link ID][email protected][hex_value]=0xFFFE+SUBSTRING([hex_value], 9, LEN([hex_value]))
--,[Update]=[Update]+1WHERE[system_type_id]=241CREATETABLE[#temp_Data]
(
[FieldName]VARCHAR(MAX) ,
[FieldValue]NVARCHAR(MAX) ,
[Rowlogcontents]VARBINARY(8000) ,
[Row ID]INT
)
INSERTINTO #temp_Data
SELECT NAME ,
CASEWHEN system_type_id IN ( 231, 239 )
THENLTRIM(RTRIM(CONVERT(NVARCHAR(MAX), hex_Value))) --NVARCHAR ,NCHARWHEN system_type_id IN ( 167, 175 )
THENLTRIM(RTRIM(CONVERT(VARCHAR(MAX), hex_Value))) --VARCHAR,CHARWHEN system_type_id IN ( 35 )
THENLTRIM(RTRIM(CONVERT(VARCHAR(MAX), hex_Value))) --TextWHEN system_type_id IN ( 99 )
THENLTRIM(RTRIM(CONVERT(NVARCHAR(MAX), hex_Value))) --nText WHEN system_type_id =48THENCONVERT(VARCHAR(MAX), CONVERT(TINYINT, CONVERT(BINARY(1), REVERSE(hex_Value)))) --TINY INTEGERWHEN system_type_id =52THENCONVERT(VARCHAR(MAX), CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE(hex_Value)))) --SMALL INTEGERWHEN system_type_id =56THENCONVERT(VARCHAR(MAX), CONVERT(INT, CONVERT(BINARY(4), REVERSE(hex_Value)))) -- INTEGERWHEN system_type_id =127THENCONVERT(VARCHAR(MAX), CONVERT(BIGINT, CONVERT(BINARY(8), REVERSE(hex_Value))))-- BIG INTEGERWHEN system_type_id =61THENCONVERT(VARCHAR(MAX), CONVERT(DATETIME, CONVERT(VARBINARY(8000), REVERSE(hex_Value))), 100) --DATETIMEWHEN system_type_id =58THENCONVERT(VARCHAR(MAX), CONVERT(SMALLDATETIME, CONVERT(VARBINARY(8000), REVERSE(hex_Value))), 100) --SMALL DATETIMEWHEN system_type_id =108THENCONVERT(VARCHAR(MAX), CONVERT(NUMERIC(38, 20), CONVERT(VARBINARY, CONVERT(VARBINARY(1), xprec)
+CONVERT(VARBINARY(1), xscale))
+CONVERT(VARBINARY(1), 0) + hex_Value)) --- NUMERICWHEN system_type_id =106THENCONVERT(VARCHAR(MAX), CONVERT(DECIMAL(38, 20), CONVERT(VARBINARY, CONVERT(VARBINARY(1), xprec)
+CONVERT(VARBINARY(1), xscale))
+CONVERT(VARBINARY(1), 0) + hex_Value)) --- DECIMALWHEN system_type_id IN ( 60, 122 )
THENCONVERT(VARCHAR(MAX), CONVERT(MONEY, CONVERT(VARBINARY(8000), REVERSE(hex_Value))), 2) --MONEY,SMALLMONEYWHEN system_type_id =104THENCONVERT(VARCHAR(MAX), CONVERT (BIT, CONVERT(BINARY(1), hex_Value)
%2)) -- BITWHEN system_type_id =62THENRTRIM(LTRIM(STR(CONVERT(FLOAT, SIGN(CAST(CONVERT(VARBINARY(8000), REVERSE(hex_Value)) ASBIGINT))
* ( 1.0+ ( CAST(CONVERT(VARBINARY(8000), REVERSE(hex_Value)) ASBIGINT)
&0x000FFFFFFFFFFFFF )
*POWER(CAST(2ASFLOAT),
-52) )
*POWER(CAST(2ASFLOAT),
( ( CAST(CONVERT(VARBINARY(8000), REVERSE(hex_Value)) ASBIGINT)
&0x7ff0000000000000 )
/EXP(52*LOG(2))
-1023 ))), 53,
LEN(hex_Value)))) --- FLOATWHEN system_type_id =59THENLEFT(LTRIM(STR(CAST(SIGN(CAST(CONVERT(VARBINARY(8000), REVERSE(hex_Value)) ASBIGINT))
* ( 1.0+ ( CAST(CONVERT(VARBINARY(8000), REVERSE(hex_Value)) ASBIGINT)
&0x007FFFFF )
*POWER(CAST(2ASREAL), -23) )
*POWER(CAST(2ASREAL),
( ( ( CAST(CONVERT(VARBINARY(8000), REVERSE(hex_Value)) ASINT) )
&0x7f800000 )
/EXP(23*LOG(2))
-127 )) ASREAL), 23,
23)), 8) --RealWHEN system_type_id IN ( 165, 173 )
THEN ( CASEWHENCHARINDEX(0x,
CAST(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_Value"))‘,
‘VARBINARY(8000)‘)) =0THEN‘0x‘ELSE‘‘END ) +CAST(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_Value"))‘,
‘varchar(max)‘) -- BINARY,VARBINARYWHEN system_type_id =34THEN ( CASEWHENCHARINDEX(0x,
CAST(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_Value"))‘,
‘VARBINARY(8000)‘)) =0THEN‘0x‘ELSE‘‘END ) +CAST(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_Value"))‘,
‘varchar(max)‘) --IMAGEWHEN system_type_id =36THENCONVERT(VARCHAR(MAX), CONVERT(UNIQUEIDENTIFIER, hex_Value)) --UNIQUEIDENTIFIERWHEN system_type_id =231THENCONVERT(VARCHAR(MAX), CONVERT(SYSNAME, hex_Value)) --SYSNAMEWHEN system_type_id =241THENCONVERT(VARCHAR(MAX), CONVERT(XML, hex_Value)) --XMLWHEN system_type_id =189THEN ( CASEWHENCHARINDEX(0x,
CAST(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_Value"))‘,
‘VARBINARY(8000)‘)) =0THEN‘0x‘ELSE‘‘END ) +CAST(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_Value"))‘,
‘varchar(max)‘) --TIMESTAMPWHEN system_type_id =98THEN ( CASEWHENCONVERT(INT, SUBSTRING(hex_Value, 1,
1)) =56THENCONVERT(VARCHAR(MAX), CONVERT(INT, CONVERT(BINARY(4), REVERSE(SUBSTRING(hex_Value,
3,
LEN(hex_Value)))))) -- INTEGERWHENCONVERT(INT, SUBSTRING(hex_Value, 1,
1)) =108THENCONVERT(VARCHAR(MAX), CONVERT(NUMERIC(38,
20), CONVERT(VARBINARY(1), SUBSTRING(hex_Value,
3, 1))
+CONVERT(VARBINARY(1), SUBSTRING(hex_Value,
4, 1))
+CONVERT(VARBINARY(1), 0)
+SUBSTRING(hex_Value, 5,
LEN(hex_Value)))) --- NUMERICWHENCONVERT(INT, SUBSTRING(hex_Value, 1,
1)) =167THENLTRIM(RTRIM(CONVERT(VARCHAR(MAX), SUBSTRING(hex_Value,
9,
LEN(hex_Value))))) --VARCHAR,CHARWHENCONVERT(INT, SUBSTRING(hex_Value, 1,
1)) =36THENCONVERT(VARCHAR(MAX), CONVERT(UNIQUEIDENTIFIER, SUBSTRING(( hex_Value ),
3, 20))) --UNIQUEIDENTIFIERWHENCONVERT(INT, SUBSTRING(hex_Value, 1,
1)) =61THENCONVERT(VARCHAR(MAX), CONVERT(DATETIME, CONVERT(VARBINARY(8000), REVERSE(SUBSTRING(hex_Value,
3,
LEN(hex_Value))))), 100) --DATETIMEWHENCONVERT(INT, SUBSTRING(hex_Value, 1,
1)) =165THEN‘0x‘+SUBSTRING(( CASEWHENCHARINDEX(0x,
CAST(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_Value"))‘,
‘VARBINARY(8000)‘)) =0THEN‘0x‘ELSE‘‘END )
+CAST(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_Value"))‘,
‘varchar(max)‘),
11, LEN(hex_Value)) -- BINARY,VARBINARYEND )
ENDAS FieldValue ,
[Rowlogcontents] ,
[Row ID][email protected] nullbit
--Create the column name in the same order to do pivot [email protected](MAX)
[email protected]=STUFF(( SELECT‘,‘+CAST(QUOTENAME([Name]) ASVARCHAR(MAX))
FROM syscolumns
WHERE id =OBJECT_ID(‘‘[email protected]aName_n_TableName+‘‘)
FOR
XML PATH(‘‘)
), 1, 1, ‘‘)
--Finally did pivot table and get the data back in the same [email protected]=‘SELECT ‘[email protected]+‘ FROM #temp_Data PIVOT (Min([FieldValue]) FOR FieldName IN (‘[email protected]+‘)) AS pvt‘EXEC sp_executesql @sqlGO
恢复你的数据
--恢复数据，不加时间段条件 参数：数据库名，表名 --EXAMPLE #1 : FOR ALL DELETED RECORDSEXEC Recover_Deleted_Data_Proc ‘test‘,‘dbo.aa‘GO--恢复数据，加时间段条件 --EXAMPLE #2 : FOR ANY SPECIFIC DATE RANGEEXEC Recover_Deleted_Data_Proc ‘test‘,‘dbo.aa‘,‘2014-04-23‘,‘2014-04-23‘
执行了下面的存储过程之后你会发现会显示出刚才删除的数据
EXEC Recover_Deleted_Data_Proc ‘test‘,‘dbo.aa‘GO
解释
究竟他是如何工作的?让我们来一步一步来,这个过程涉及到7个步骤:
步骤1:
我们需要获得SQLSERVER删除的数据记录.使用标准SQLSERVER函数fn_dblog，我们能够容易的获得事务日志记录（包括
已删的数据。不过，我们只需要事务日志中选中的被删数据，所以我们的过滤条件需要包含3个字段 Context, Operation & AllocUnitName）
We need to get the deleted records from sql server. By using the standard SQL Server function fn_blog, we can easily get all transaction log (Including deleted data. But, we need only the selected deleted records from the transaction log. So we included three filters (Context, Operation , AllocUnitName).
- Context (‘LCX_MARK_AS_GHOST’and ‘LCX_HEAP’)
- Operation (‘LOP_DELETE_ROWS’)
- AllocUnitName(‘dbo.aa’) –- Schema + table Name
Context可以说明是堆表还是聚集表
Operation：删除操作
AllocUnitName：分配单元名称，表名
下面是一个代码片段
SELECT[RowLog Contents 0]FROM sys.fn_dblog(NULL, NULL)
WHERE AllocUnitName =‘dbo.aa‘AND Context IN ( ‘LCX_MARK_AS_GHOST‘, ‘LCX_HEAP‘ )
AND Operation IN ( ‘LOP_DELETE_ROWS‘ )
这个查询会返回不同列的信息，但是我们只需要选择[RowLog Contents 0]列，去获得被删除的数据的内容
RowLog content 0列的内容类似于这样
“0x300018000100000000000000006B0000564920205900000
00500E001002800426F62206A65727279″
步骤2:
现在，我们已经删除了数据，这些数据以hex码的形式放在事务日志里，这些hex码是有规律的，我们根据这些规律可以很容易恢复这些数据。
不过在恢复这些数据之前，我们需要理解这些格式。这些格式在KalenDelaney’s SQL Internal’s book.的书里面有讲解
- 1 Byte : Status Bit A
- 1 Byte : Status Bit B
- 2 Bytes : Fixed length size
- n Bytes : Fixed length data
- 2 Bytes : Total Number of Columns
- n Bytes : NULL Bitmap (1 bit for each column as 1 indicates that the column is null and 0 indicate that the column is not null)
- 2 Bytes : Number of variable-length columns
- n Bytes : Column offset array (2x variable length column)
- n Bytes : Data for variable length columns
所以, hex码的“RowLog content 0″列的内容就等价于
“Status Bit A +Status Bit B +Fixed length size +Fixed length data +Total Number of Columns +NULL Bitmap +Number of variable-length columns +NULL Bitmap+Number of variable-length columns +Column offset array +Data for variable length columns.”
更详细的可以参考：SQL Server2008存储结构之堆表、行溢出
关于数据行的结构我们还可以采用稍微宏观一些的视角来查看。
步骤3:
现在，我们需要解剖RowLog Content o列的内容（我们删除的数据的Hex码），利用上面的数据行的结构
- [Fixed Length Data] = Substring (RowLog content 0, Status Bit A+Status Bit B + 1,2 bytes)
- [Total No of Columns]= Substring (RowLog content 0, [Fixed Length Data] + 1,2 bytes)
- [Null Bitmap length] = Ceiling ([Total No of Columns]/8.0)
- [Null Bytes]= Substring (RowLog content 0, Status Bit A+ Status Bit B +[Fixed Length Data] +1, [Null Bitmap length] )
- Total no of variable columns = Substring (RowLog content 0, Status Bit A+ Status Bit B + [Fixed Length Data] +1, [Null Bitmap length] + 2 )
- Column Offset Array= Substring (RowLog content 0, Status Bit A+ Status Bit B + [Fixed Length Data] +1, [Null Bitmap length] + 2 , Total no of variable columns*2 )
- Variable Column Start = Status Bit A+ Status Bit B + [Fixed Length Data] + [Null Bitmap length] + 2+( Total no of variable columns*2)
步骤4:
现在我们已经将hex码切开了(0x300008000100000002000001001300604F7D59),所以,我们能找到删除的行的某列的数据是否为null值
根据NULL位图。为了完成将NULL Bytes的hex码转换为二进制格式（正如之前讨论的，1表示行中对应的那一列为null，而0则表示对应的列有实际的数据）
如果还不是明白的童鞋可以看一下我写的这篇文章：《SQLSERVER中NULL位图的作用》
步骤5:
现在，我们已经做了初步的数据分割 (Step-3) 和null值判断(Step-4) 。然后我们需要使用代码片段去获得列数据，例如：列名，列大小，精度，范围
和最重要的叶子的null位（确保列数据是固定长度的（<=-1表示可变长度）或者固定长度的（>=1））
使用下面的SQL语句
SELECT*FROM sys.allocation_units allocunits
INNERJOIN sys.partitions partitions ON ( allocunits.type IN ( 1, 3 )
AND partitions.hobt_id = allocunits.container_id
)
OR ( allocunits.type =2AND partitions.partition_id = allocunits.container_id
)
INNERJOIN sys.system_internals_partition_columns cols ON cols.partition_id = partitions.partition_id
LEFTOUTERJOIN syscolumns ON syscolumns.id = partitions.object_idAND syscolumns.colid = cols.partition_column_id
与(Step-1,2,3,4) 获得的数据表做join连接，根据allocunits.[Allocation_Unit_Id]。
现在我们知道表和表中的数据信息，那么我们需要利用这些数据去将 [RowLog Contents 0] 列里的hex码的数据插入到表中的相应列
现在我们需要关心每一列的数据究竟是固定长度的还是可变长度的
步骤6:
我们收集了每列的hex格式的数据。现在我们需要利用[System_type_id]去转换这些数据回去正确的数据类型
每一种数据类型都有不同的数据类型转换机制。
--NVARCHAR ,NCHARWHEN system_type_id IN (231, 239) THENLTRIM(RTRIM(CONVERT(NVARCHAR(max),hex_Value)))
--VARCHAR,CHARWHEN system_type_id IN (167,175) THENLTRIM(RTRIM(CONVERT(VARCHAR(max),REPLACE(hex_Value, 0x00, 0x20))))
--TINY INTEGERWHEN system_type_id =48THENCONVERT(VARCHAR(MAX), CONVERT(TINYINT, CONVERT(BINARY(1), REVERSE (hex_Value))))
--SMALL INTEGERWHEN system_type_id =52THENCONVERT(VARCHAR(MAX), CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE (hex_Value))))
-- INTEGERWHEN system_type_id =56THENCONVERT(VARCHAR(MAX), CONVERT(INT, CONVERT(BINARY(4), REVERSE(hex_Value))))
-- BIG INTEGERWHEN system_type_id =127THENCONVERT(VARCHAR(MAX), CONVERT(BIGINT, CONVERT(BINARY(8), REVERSE(hex_Value))))
--DATETIMEWHEN system_type_id =61ThenCONVERT(VARCHAR(Max),CONVERT(DATETIME,Convert(VARBINARY(max),REVERSE (hex_Value))),100)
--SMALL DATETIMEWHEN system_type_id =58ThenCONVERT(VARCHAR(Max),CONVERT(SMALLDATETIME,CONVERT(VARBINARY(MAX),REVERSE(hex_Value))),100) --SMALL DATETIME--- NUMERICWHEN system_type_id =108THENCONVERT(VARCHAR(MAX), CAST(CONVERT(NUMERIC(18,14), CONVERT(VARBINARY,CONVERT(VARBINARY,xprec)+CONVERT(VARBINARY,xscale))+CONVERT(VARBINARY(1),0) + hex_Value) asFLOAT))
--MONEY,SMALLMONEYWHEN system_type_id In(60,122) THENCONVERT(VARCHAR(MAX),Convert(MONEY,Convert(VARBINARY(MAX),Reverse(hex_Value))),2)
--- DECIMALWHEN system_type_id =106THENCONVERT(VARCHAR(MAX), CAST(CONVERT(Decimal(38,34), Convert(VARBINARY,Convert(VARBINARY,xprec)+CONVERT(VARBINARY,xscale))+CONVERT(VARBINARY(1),0) + hex_Value) asFLOAT))
-- BITWHEN system_type_id =104THENCONVERT(VARCHAR(MAX),CONVERT (BIT,CONVERT(BINARY(1), hex_Value)%2))
--- FLOATWHEN system_type_id =62THENRTRIM(LTRIM(Str(Convert(FLOAT,SIGN(CAST(Convert(VARBINARY(max),Reverse(hex_Value)) ASBIGINT)) * (1.0+ (CAST(CONVERT(VARBINARY(max),Reverse(hex_Value)) ASBIGINT) &0x000FFFFFFFFFFFFF) *POWER(CAST(2ASFLOAT), -52)) *POWER(CAST(2ASFLOAT),((CAST(CONVERT(VARBINARY(max),Reverse(hex_Value)) ASBIGINT) &0x7ff0000000000000) /EXP(52*LOG(2))-1023))),53,LEN(hex_Value))))
--REALWhen system_type_id =59THENLeft(LTRIM(STR(Cast(SIGN(CAST(Convert(VARBINARY(max),Reverse(hex_Value)) ASBIGINT))* (1.0+ (CAST(CONVERT(VARBINARY(max),Reverse(hex_Value)) ASBIGINT) &0x007FFFFF) *POWER(CAST(2ASReal), -23)) *POWER(CAST(2ASReal),(((CAST(CONVERT(VARBINARY(max),Reverse(hex_Value)) ASINT) )&0x7f800000)/EXP(23*LOG(2))-127))ASREAL),23,23)),8)
--BINARY,VARBINARYWHEN system_type_id In (165,173) THEN (CASEWHENCharindex(0x,cast(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_value"))‘, ‘varbinary(max)‘)) =0THEN‘0x‘ELSE‘‘END) +cast(‘‘AS XML).value(‘xs:hexBinary(sql:column("hex_value"))‘, ‘varchar(max)‘)
--UNIQUEIDENTIFIER WHEN system_type_id =36THENCONVERT(VARCHAR(MAX),CONVERT(UNIQUEIDENTIFIER,hex_Value))
步骤7:
最终我们做一个数据透视表，你会看到最后的结果：被删的数据回来了！
注意：这些数据只是展示出来并没有自动插入回表中，你需要将这些数据重新插入回去表中！
我的测试
经过测试，作者写的这个存储过程还是有些问题
如果你创建的测试表的数据类型有xml或者是一些text数据类型的字段会有报错
Msg 537, Level16, State 3, Procedure Recover_Deleted_Data_Proc, Line 525 Invalid length parameter passed to the LEFTorSUBSTRINGfunction. Msg 9420, Level16, State 1, Procedure Recover_Deleted_Data_Proc, Line 651 XML parsing: line 1, character2, illegal xml character
但是一般的数据类型则不会，例如nvarchar这些
还有不要在存储过程的最后加
--Recover the deleted data without date rangeEXEC Recover_Deleted_Data_Proc ‘test‘,‘dbo.Test_Table‘GO--Recover the deleted data it with date rangeEXEC Recover_Deleted_Data_Proc ‘test‘,‘dbo.Test_Table‘,‘2012-06-01‘,‘2012-06-30‘
否则会报错
消息 50000，级别 16，状态 1，过程 Recover_Deleted_Data_Proc，第 290 行 There is no data in the logas per the search criteria
总结
实际上这个存储过程还是挺有研究意义的，对于想做一个跟Log Explorer for SQL Server软件功能差不多的软件出来
还是有可能的，跟着作者的思路，一步一步实现
苦于最近太忙，先分享出来，以后再研究这个存储过程了~
时间： 2024-10-10 22:27:33