[翻译]如何从 SQL Server 恢复已删除的数据
[翻译]如何从 SQL Server 恢复已删除的数据
保持热爱奔赴山海
修改于 2024-05-10 14:49:41
修改于 2024-05-10 14:49:41
在我使用 SQL Server 的这些年里，最常见的问题之一一直是“我们如何恢复已删除的记录？”
现在，从 SQL Server 2005 或更高版本恢复已删除的数据非常容易。（注意：此脚本可以恢复以下数据类型并与 CS 排序规则兼容）。
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让我用简单的例子来解释这个问题。
--Create Table
Create Table [Test_Table]
(
[Col_image] image,
[Col_text] text,
[Col_uniqueidentifier] uniqueidentifier,
[Col_tinyint] tinyint,
[Col_smallint] smallint,
[Col_int] int,
[Col_smalldatetime] smalldatetime,
[Col_real] real,
[Col_money] money,
[Col_datetime] datetime,
[Col_float] float,
[Col_Int_sql_variant] sql_variant,
[Col_numeric_sql_variant] sql_variant,
[Col_varchar_sql_variant] sql_variant,
[Col_uniqueidentifier_sql_variant] sql_variant,
[Col_Date_sql_variant] sql_variant,
[Col_varbinary_sql_variant] sql_variant,
[Col_ntext] ntext,
[Col_bit] bit,
[Col_decimal] decimal(18,4),
[Col_numeric] numeric(18,4),
[Col_smallmoney] smallmoney,
[Col_bigint] bigint,
[Col_varbinary] varbinary(Max),
[Col_varchar] varchar(Max),
[Col_binary] binary(8),
[Col_char] char,
[Col_timestamp] timestamp,
[Col_nvarchar] nvarchar(Max),
[Col_nchar] nchar,
[Col_xml] xml,
[Col_sysname] sysname
)
GO
--Insert data into it
INSERT INTO [Test_Table]
([Col_image]
,[Col_text]
,[Col_uniqueidentifier]
,[Col_tinyint]
,[Col_smallint]
,[Col_int]
,[Col_smalldatetime]
,[Col_real]
,[Col_money]
,[Col_datetime]
,[Col_float]
,[Col_Int_sql_variant]
,[Col_numeric_sql_variant]
,[Col_varchar_sql_variant]
,[Col_uniqueidentifier_sql_variant]
,[Col_Date_sql_variant]
,[Col_varbinary_sql_variant]
,[Col_ntext]
,[Col_bit]
,[Col_decimal]
,[Col_numeric]
,[Col_smallmoney]
,[Col_bigint]
,[Col_varbinary]
,[Col_varchar]
,[Col_binary]
,[Col_char]
,[Col_nvarchar]
,[Col_nchar]
,[Col_xml]
,[Col_sysname])
VALUES
(CONVERT(IMAGE,REPLICATE('A',4000))
,REPLICATE('B',8000)
,NEWID()
,10
,20
,3000
,GETDATE()
,4000
,5000
,getdate()+15
,66666.6666
,777777
,88888.8888
,REPLICATE('C',8000)
,newid()
,getdate()+30
,CONVERT(VARBINARY(8000),REPLICATE('D',8000))
,REPLICATE('E',4000)
,1
,99999.9999
,10101.1111
,1100
,123456
,CONVERT(VARBINARY(MAX),REPLICATE('F',8000))
,REPLICATE('G',8000)
,0x4646464
,'H'
,REPLICATE('I',4000)
,'J'
,CONVERT(XML,REPLICATE('K',4000))
,REPLICATE('L',100)
)
GO
--Delete the data
Delete from Test_Table
Go
--Verify the data
Select * from Test_Table
Go
--Recover the deleted data without date range
EXEC Recover_Deleted_Data_Proc 'test','dbo.Test_Table'
GO
--Recover the deleted data it with date range
EXEC Recover_Deleted_Data_Proc 'test','dbo.Test_Table','2012-06-01','2012-06-30'存储过程内容如下
-- 下载地址 https://app.box.com/s/lwm6opi4yyqemxmw1aa4
-- 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.
--DROP PROCEDURE Recover_Deleted_Data_Proc
--GO
Create PROCEDURE Recover_Deleted_Data_Proc
@Database_Name NVARCHAR(MAX),
@SchemaName_n_TableName NVARCHAR(Max),
@Date_From DATETIME='1900/01/01',
@Date_To DATETIME ='9999/12/31'
AS
DECLARE @RowLogContents VARBINARY(8000)
DECLARE @TransactionID NVARCHAR(Max)
DECLARE @AllocUnitID BIGINT
DECLARE @AllocUnitName NVARCHAR(Max)
DECLARE @SQL NVARCHAR(Max)
DECLARE @Compatibility_Level INT
SELECT @Compatibility_Level=dtb.compatibility_level
FROM
master.sys.databases AS dtb WHERE dtb.name=@Database_Name
IF ISNULL(@Compatibility_Level,0)<=80
BEGIN
RAISERROR('The compatibility level should be equal to or greater SQL SERVER 2005 (90)',16,1)
RETURN
END
IF (SELECT COUNT(*) FROM INFORMATION_SCHEMA.TABLES WHERE [TABLE_SCHEMA]+'.'+[TABLE_NAME]=@SchemaName_n_TableName)=0
BEGIN
RAISERROR('Could not found the table in the defined database',16,1)
RETURN
END
DECLARE @bitTable TABLE
(
[ID] INT,
[Bitvalue] INT
)
--Create table to set the bit position of one byte.
INSERT INTO @bitTable
SELECT 0,2 UNION ALL
SELECT 1,2 UNION ALL
SELECT 2,4 UNION ALL
SELECT 3,8 UNION ALL
SELECT 4,16 UNION ALL
SELECT 5,32 UNION ALL
SELECT 6,64 UNION ALL
SELECT 7,128
--Create table to collect the row data.
DECLARE @DeletedRecords TABLE
(
[Row ID] INT IDENTITY(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] --@FixedLengthData
-- [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 )
,(CASE WHEN SUBSTRING([RowLog Contents 0], 1, 1) In (0x10,0x30,0x70) THEN
CONVERT(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)))) ELSE null END) AS [TotalNoofVarCols]
--[ColumnOffsetArray]= Substring (RowLog content 0, Status Bit A+ Status Bit B + [Fixed Length Data] +1, [Null Bitmap length] + 2 , [TotalNoofVarCols]*2 )
,(CASE WHEN SUBSTRING([RowLog Contents 0], 1, 1) In (0x10,0x30,0x70) THEN
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
, (CASE WHEN SUBSTRING([RowLog Contents 0], 1, 1) In (0x10,0x30,0x70) THEN
CONVERT(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)))) ELSE null END)
* 2) ELSE null END) AS [ColumnOffsetArray]
-- Variable column Start = Status Bit A+ Status Bit B + [Fixed Length Data] + [Null Bitmap length] + 2+([TotalNoofVarCols]*2)
,CASE WHEN SUBSTRING([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))
+ ((CASE WHEN SUBSTRING([RowLog Contents 0], 1, 1) In (0x10,0x30,0x70) THEN
CONVERT(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)))) ELSE null END) * 2))
ELSE null End AS [VarColumnStart]
,[Slot ID]
FROM sys.fn_dblog(NULL, NULL)
WHERE
AllocUnitId IN
(SELECT [Allocation_unit_id] FROM sys.allocation_units allocunits
INNER JOIN sys.partitions partitions ON (allocunits.type IN (1, 3)
AND partitions.hobt_id = allocunits.container_id) OR (allocunits.type = 2
AND partitions.partition_id = allocunits.container_id)
WHERE object_id=object_ID('' + @SchemaName_n_TableName + ''))
AND Context IN ('LCX_MARK_AS_GHOST', 'LCX_HEAP') AND Operation in ('LOP_DELETE_ROWS')
And SUBSTRING([RowLog Contents 0], 1, 1)In (0x10,0x30,0x70)
/*Use this subquery to filter the date*/
AND [TRANSACTION ID] IN (SELECT DISTINCT [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')
And CONVERT(NVARCHAR(11),[Begin Time]) BETWEEN @Date_From AND @Date_To)),
--Use this technique to repeate the row till the no of bytes of the row.
N1 (n) AS (SELECT 1 UNION ALL SELECT 1),
N2 (n) AS (SELECT 1 FROM N1 AS X, N1 AS Y),
N3 (n) AS (SELECT 1 FROM N2 AS X, N2 AS Y),
N4 (n) AS (SELECT ROW_NUMBER() OVER(ORDER BY X.n)
FROM N3 AS X, N3 AS Y)
INSERT INTO @DeletedRecords
SELECT 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 ',' +
(CASE WHEN [ID]=0 THEN CONVERT(NVARCHAR(1),(SUBSTRING(NullBytes, n, 1) % 2)) ELSE CONVERT(NVARCHAR(1),((SUBSTRING(NullBytes, n, 1) / [Bitvalue]) % 2)) END) --as [nullBitMap]
FROM
N4 AS Nums
Join RowData AS C ON n<=NullBitMapLength
Cross Join @bitTable WHERE C.[RowLogContents]=D.[RowLogContents] ORDER BY [RowLogContents],n ASC FOR XML PATH('')),1,1,''),',',''))
FROM RowData D
IF (SELECT COUNT(*) FROM @DeletedRecords)=0
BEGIN
RAISERROR('There is no data in the log as per the search criteria',16,1)
RETURN
END
DECLARE @ColumnNameAndData TABLE
(
[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*/
--@RowLogContents,
--(col.columnOffValue - col.columnLength) + 1,
--col.columnLength
--)
INSERT INTO @ColumnNameAndData
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,
(CASE WHEN leaf_offset<1 and SUBSTRING([nullBitMap], cols.leaf_null_bit, 1)=0
THEN
(Case When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) >30000
THEN
CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) - POWER(2, 15)
ELSE
CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2))))
END)
END) AS [Column value Size],
(CASE WHEN leaf_offset<1 and SUBSTRING([nullBitMap], cols.leaf_null_bit, 1)=0 THEN
(Case
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) >30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])<30000
THEN (Case When [System_type_id]In (35,34,99) Then 16 else 24 end)
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) >30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])>30000
THEN (Case When [System_type_id]In (35,34,99) Then 16 else 24 end) --24
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) <30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])<30000
THEN (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]))
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) <30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])>30000
THEN POWER(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]
,(CASE WHEN SUBSTRING([nullBitMap], cols.leaf_null_bit, 1)=1 THEN NULL ELSE
SUBSTRING
(
Rowlogcontents,
(
(Case When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) >30000
THEN
CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) - POWER(2, 15)
ELSE
CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2))))
END)
-
(Case When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) >30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])<30000
THEN (Case When [System_type_id]In (35,34,99) Then 16 else 24 end) --24
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) >30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])>30000
THEN (Case When [System_type_id]In (35,34,99) Then 16 else 24 end) --24
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) <30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])<30000
THEN 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])
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) <30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])>30000
THEN POWER(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,
(Case When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) >30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])<30000
THEN (Case When [System_type_id] In (35,34,99) Then 16 else 24 end) --24
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) >30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])>30000
THEN (Case When [System_type_id] In (35,34,99) Then 16 else 24 end) --24
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) <30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])<30000
THEN ABS(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]))
When CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * leaf_offset*-1) - 1, 2)))) <30000 And
ISNULL(NULLIF(CONVERT(INT, CONVERT(BINARY(2), REVERSE (SUBSTRING ([ColumnOffsetArray], (2 * ((leaf_offset*-1) - 1)) - 1, 2)))), 0), [varColumnStart])>30000
THEN POWER(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]
,0
FROM @DeletedRecords A
Inner Join sys.allocation_units allocunits On A.[AllocUnitId]=allocunits.[Allocation_Unit_Id]
INNER JOIN sys.partitions partitions ON (allocunits.type IN (1, 3)
AND partitions.hobt_id = allocunits.container_id) OR (allocunits.type = 2 AND partitions.partition_id = allocunits.container_id)
INNER JOIN sys.system_internals_partition_columns cols ON cols.partition_id = partitions.partition_id
LEFT OUTER JOIN syscolumns ON syscolumns.id = partitions.object_id AND syscolumns.colid = cols.partition_column_id
WHERE leaf_offset<0
UNION
/*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,
(SELECT TOP 1 ISNULL(SUM(CASE WHEN C.leaf_offset >1 THEN max_length ELSE 0 END),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 AS [Column value Size],
syscolumns.length AS [Column Length]
,CASE WHEN SUBSTRING([nullBitMap], cols.leaf_null_bit, 1)=1 THEN NULL ELSE
SUBSTRING
(
Rowlogcontents,(SELECT TOP 1 ISNULL(SUM(CASE WHEN C.leaf_offset >1 And C.leaf_bit_position=0 THEN max_length ELSE 0 END),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) END AS hex_Value
,[Slot ID]
,0
FROM @DeletedRecords A
Inner Join sys.allocation_units allocunits ON A.[AllocUnitId]=allocunits.[Allocation_Unit_Id]
INNER JOIN sys.partitions partitions ON (allocunits.type IN (1, 3)
AND partitions.hobt_id = allocunits.container_id) OR (allocunits.type = 2 AND partitions.partition_id = allocunits.container_id)
INNER JOIN sys.system_internals_partition_columns cols ON cols.partition_id = partitions.partition_id
LEFT OUTER JOIN syscolumns ON syscolumns.id = partitions.object_id AND syscolumns.colid = cols.partition_column_id
WHERE leaf_offset>0
Order By nullbit
Declare @BitColumnByte as int
Select @BitColumnByte=CONVERT(INT, ceiling( Count(*)/8.0)) from @ColumnNameAndData Where [System_Type_id]=104
;With N1 (n) AS (SELECT 1 UNION ALL SELECT 1),
N2 (n) AS (SELECT 1 FROM N1 AS X, N1 AS Y),
N3 (n) AS (SELECT 1 FROM N2 AS X, N2 AS Y),
N4 (n) AS (SELECT ROW_NUMBER() OVER(ORDER BY X.n)
FROM N3 AS X, N3 AS Y),
CTE As(
Select RowLogContents,[nullbit]
,[BitMap]=Convert(varbinary(1),Convert(int,Substring((REPLACE(STUFF((SELECT ',' +
(CASE WHEN [ID]=0 THEN CONVERT(NVARCHAR(1),(SUBSTRING(hex_Value, n, 1) % 2)) ELSE CONVERT(NVARCHAR(1),((SUBSTRING(hex_Value, n, 1) / [Bitvalue]) % 2)) END) --as [nullBitMap]
from N4 AS Nums
Join @ColumnNameAndData AS C ON n<=@BitColumnByte And [System_Type_id]=104 And bitpos=0
Cross Join @bitTable WHERE C.[RowLogContents]=D.[RowLogContents] ORDER BY [RowLogContents],n ASC FOR XML PATH('')),1,1,''),',','')),bitpos+1,1)))
FROM @ColumnNameAndData D Where [System_Type_id]=104)
Update A Set [hex_Value]=[BitMap]
from @ColumnNameAndData A
Inner Join CTE B On A.[RowLogContents]=B.[RowLogContents]
And A.[nullbit]=B.[nullbit]
/**************Check for BLOB DATA TYPES******************************/
DECLARE @Fileid INT
DECLARE @Pageid INT
DECLARE @Slotid INT
DECLARE @CurrentLSN INT
DECLARE @LinkID INT
DECLARE @Context VARCHAR(50)
DECLARE @ConsolidatedPageID VARCHAR(MAX)
DECLARE @LCX_TEXT_MIX VARBINARY(MAX)
declare @temppagedata table
(
[ParentObject] sysname,
[Object] sysname,
[Field] sysname,
[Value] sysname)
declare @pagedata table
(
[Page ID] sysname,
[File IDS] int,
[Page IDS] int,
[AllocUnitId] bigint,
[ParentObject] sysname,
[Object] sysname,
[Field] sysname,
[Value] sysname)
DECLARE @ModifiedRawData TABLE
(
[ID] INT IDENTITY(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] INT default (0),
[Update] INT
)
DECLARE Page_Data_Cursor CURSOR FOR
/*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*/
SELECT LTRIM(RTRIM(Replace([Description],'Deallocated',''))) AS [PAGE ID]
,[Slot ID],[AllocUnitId],NULL AS [RowLog Contents 0],NULL AS [RowLog Contents 0],Context
FROM sys.fn_dblog(NULL, NULL)
WHERE
AllocUnitId IN
(SELECT [Allocation_unit_id] FROM sys.allocation_units allocunits
INNER JOIN sys.partitions partitions ON (allocunits.type IN (1, 3)
AND partitions.hobt_id = allocunits.container_id) OR (allocunits.type = 2
AND partitions.partition_id = allocunits.container_id)
WHERE object_id=object_ID('' + @SchemaName_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 (SELECT DISTINCT [TRANSACTION ID] FROM sys.fn_dblog(NULL, NULL)
WHERE Context IN ('LCX_NULL') AND Operation in ('LOP_BEGIN_XACT')
AND [Transaction Name]='DELETE'
AND CONVERT(NVARCHAR(11),[Begin Time]) BETWEEN @Date_From AND @Date_To)
GROUP BY [Description],[Slot ID],[AllocUnitId],Context
UNION
SELECT [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
INNER JOIN sys.partitions partitions ON (allocunits.type IN (1, 3)
AND partitions.hobt_id = allocunits.container_id) OR (allocunits.type = 2
AND partitions.partition_id = allocunits.container_id)
WHERE object_id=object_ID('' + @SchemaName_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 (SELECT DISTINCT [TRANSACTION ID] FROM sys.fn_dblog(NULL, NULL)
WHERE Context IN ('LCX_NULL') AND Operation in ('LOP_BEGIN_XACT')
And [Transaction Name]='DELETE'
And CONVERT(NVARCHAR(11),[Begin Time]) BETWEEN @Date_From AND @Date_To)
/****************************************/
OPEN Page_Data_Cursor
FETCH NEXT FROM Page_Data_Cursor INTO @ConsolidatedPageID, @Slotid,@AllocUnitID,@LCX_TEXT_MIX,@LinkID,@Context
WHILE @@FETCH_STATUS = 0
BEGIN
DECLARE @hex_pageid AS VARCHAR(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*/
SET @Fileid=SUBSTRING(@ConsolidatedPageID,0,CHARINDEX(':',@ConsolidatedPageID)) -- Seperate File ID from Page ID
SET @hex_pageid ='0x'+ SUBSTRING(@ConsolidatedPageID,CHARINDEX(':',@ConsolidatedPageID)+1,Len(@ConsolidatedPageID)) ---Seperate the page ID
SELECT @Pageid=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 integer
FROM (SELECT CASE substring(@hex_pageid, 1, 2) WHEN '0x' THEN 3 ELSE 0 END) AS t(pos)
IF @Context='LCX_PFS'
BEGIN
DELETE @temppagedata
INSERT INTO @temppagedata EXEC( 'DBCC PAGE(' + @DataBase_Name + ', ' + @fileid + ', ' + @pageid + ', 1) with tableresults,no_infomsgs;');
INSERT INTO @pagedata SELECT @ConsolidatedPageID,@fileid,@pageid,@AllocUnitID,[ParentObject],[Object],[Field] ,[Value] FROM @temppagedata
END
ELSE IF @Context='LCX_TEXT_MIX'
BEGIN
INSERT INTO @ModifiedRawData SELECT @ConsolidatedPageID,@fileid,@pageid,@Slotid,@AllocUnitID,NULL,0,CONVERT(INT,CONVERT(VARBINARY,REVERSE(SUBSTRING(@LCX_TEXT_MIX,11,2)))),@LCX_TEXT_MIX,@LinkID,0
END
FETCH NEXT FROM Page_Data_Cursor INTO @ConsolidatedPageID, @Slotid,@AllocUnitID,@LCX_TEXT_MIX,@LinkID,@Context
END
CLOSE Page_Data_Cursor
DEALLOCATE Page_Data_Cursor
DECLARE @Newhexstring VARCHAR(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 format
INSERT INTO @ModifiedRawData ([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((
SELECT
REPLACE(STUFF((SELECT REPLACE(SUBSTRING([Value],CHARINDEX(':',[Value])+1,CHARINDEX('†',[Value])-CHARINDEX(':',[Value])),'†','')
FROM @pagedata C WHERE B.[Page ID]= C.[Page ID] And Substring(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%' Order By '0x'+ LEFT([Value],CHARINDEX(':',[Value])-1)
FOR XML PATH('') ),1,1,'') ,' ','')
),1,20000) AS [Value]
,
Substring((
SELECT '0x' +REPLACE(STUFF((SELECT REPLACE(SUBSTRING([Value],CHARINDEX(':',[Value])+1,CHARINDEX('†',[Value])-CHARINDEX(':',[Value])),'†','')
FROM @pagedata C WHERE B.[Page ID]= C.[Page ID] And Substring(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%' Order By '0x'+ LEFT([Value],CHARINDEX(':',[Value])-1)
FOR XML PATH('') ),1,1,'') ,' ','')
),7,4) AS [Length]
From @pagedata B
Where [Object] Like '%Memory Dump%'
Group By [Page ID],[FILE IDS],[PAGE IDS],[ParentObject],[AllocUnitId]--,[Current LSN]
Order By [Slot ID]
UPDATE @ModifiedRawData SET [RowLog Len] = CONVERT(VARBINARY(8000),REVERSE(cast('' AS XML).value('xs:hexBinary(substring(sql:column("[RowLog Length]"),0))', 'varbinary(Max)')))
FROM @ModifiedRawData Where [LINK ID]=0
UPDATE @ModifiedRawData SET [RowLog Contents 0] =cast('' AS XML).value('xs:hexBinary(substring(sql:column("[RowLog Contents 0_var]"),0))', 'varbinary(Max)')
FROM @ModifiedRawData Where [LINK ID]=0
Update B Set B.[RowLog Contents 0] =
(CASE WHEN A.[RowLog Contents 0] IS NOT NULL AND C.[RowLog Contents 0] IS NOT NULL THEN A.[RowLog Contents 0]+C.[RowLog Contents 0]
WHEN A.[RowLog Contents 0] IS NULL AND C.[RowLog Contents 0] IS NOT NULL THEN C.[RowLog Contents 0]
WHEN A.[RowLog Contents 0] IS NOT NULL AND C.[RowLog Contents 0] IS NULL THEN A.[RowLog Contents 0]
END)
,B.[Update]=ISNULL(B.[Update],0)+1
from @ModifiedRawData B
LEFT Join @ModifiedRawData 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]
LEFT Join @ModifiedRawData 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] IS NOT NULL OR C.[RowLog Contents 0] IS NOT NULL)
Update B Set B.[RowLog Contents 0] =
(CASE WHEN A.[RowLog Contents 0] IS NOT NULL AND C.[RowLog Contents 0] IS NOT NULL THEN A.[RowLog Contents 0]+C.[RowLog Contents 0]
WHEN A.[RowLog Contents 0] IS NULL AND C.[RowLog Contents 0] IS NOT NULL THEN C.[RowLog Contents 0]
WHEN A.[RowLog Contents 0] IS NOT NULL AND C.[RowLog Contents 0] IS NULL THEN A.[RowLog Contents 0]
END)
--,B.[Update]=ISNULL(B.[Update],0)+1
from @ModifiedRawData B
LEFT Join @ModifiedRawData 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]=0
LEFT Join @ModifiedRawData 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]=0
Where (A.[RowLog Contents 0] IS NOT NULL OR C.[RowLog Contents 0] IS NOT NULL)
UPDATE @ModifiedRawData SET [RowLog Contents 0] =
(Case When [RowLog Len]>=8000 Then
Substring([RowLog Contents 0] ,15,[RowLog Len])
When [RowLog Len]<8000 Then
SUBSTRING([RowLog Contents 0],15+6,Convert(int,Convert(varbinary(max),REVERSE(Substring([RowLog Contents 0],15,6)))))
End)
FROM @ModifiedRawData Where [LINK ID]=0
UPDATE @ColumnNameAndData SET [hex_Value]=[RowLog Contents 0]
--,A.[Update]=A.[Update]+1
FROM @ColumnNameAndData A
INNER JOIN @ModifiedRawData B ON
Convert(int,Convert(Varbinary(Max),Reverse(Substring([hex_value],17,4))))=[PAGE IDS]
AND Convert(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] <>0
UPDATE @ColumnNameAndData SET [hex_Value]=
(CASE WHEN B.[RowLog Contents 0] IS NOT NULL AND C.[RowLog Contents 0] IS NOT NULL THEN B.[RowLog Contents 0]+C.[RowLog Contents 0]
WHEN B.[RowLog Contents 0] IS NULL AND C.[RowLog Contents 0] IS NOT NULL THEN C.[RowLog Contents 0]
WHEN B.[RowLog Contents 0] IS NOT NULL AND C.[RowLog Contents 0] IS NULL THEN B.[RowLog Contents 0]
END)
--,A.[Update]=A.[Update]+1
FROM @ColumnNameAndData A
LEFT JOIN @ModifiedRawData B ON
Convert(int,Convert(Varbinary(Max),Reverse(Substring([hex_value],5,4))))=B.[PAGE IDS] And B.[Link ID] =0
LEFT JOIN @ModifiedRawData C ON
Convert(int,Convert(Varbinary(Max),Reverse(Substring([hex_value],17,4))))=C.[PAGE IDS] And C.[Link ID] =0
Where [System_Type_Id] In (99,167,175,231,239,241,165,98) And (B.[RowLog Contents 0] IS NOT NULL OR C.[RowLog Contents 0] IS NOT NULL)
UPDATE @ColumnNameAndData SET [hex_Value]=[RowLog Contents 0]
--,A.[Update]=A.[Update]+1
FROM @ColumnNameAndData A
INNER JOIN @ModifiedRawData B ON
Convert(int,Convert(Varbinary(Max),Reverse(Substring([hex_value],9,4))))=[PAGE IDS]
And Convert(int,Substring([hex_value],3,2))=[Link ID]
Where [System_Type_Id] In (35,34,99) And [Link ID] <>0
UPDATE @ColumnNameAndData SET [hex_Value]=[RowLog Contents 0]
--,A.[Update]=A.[Update]+10
FROM @ColumnNameAndData A
INNER JOIN @ModifiedRawData B ON
Convert(int,Convert(Varbinary(Max),Reverse(Substring([hex_value],9,4))))=[PAGE IDS]
Where [System_Type_Id] In (35,34,99) And [Link ID] =0
UPDATE @ColumnNameAndData SET [hex_Value]=[RowLog Contents 0]
--,A.[Update]=A.[Update]+1
FROM @ColumnNameAndData A
INNER JOIN @ModifiedRawData B ON
Convert(int,Convert(Varbinary(Max),Reverse(Substring([hex_value],15,4))))=[PAGE IDS]
Where [System_Type_Id] In (35,34,99) And [Link ID] =0
Update @ColumnNameAndData set [hex_value]= 0xFFFE + Substring([hex_value],9,LEN([hex_value]))
--,[Update]=[Update]+1
Where [system_type_id]=241
CREATE TABLE [#temp_Data]
(
[FieldName] VARCHAR(MAX),
[FieldValue] NVARCHAR(MAX),
[Rowlogcontents] VARBINARY(8000),
[Row ID] int
)
INSERT INTO #temp_Data
SELECT NAME,
CASE
WHEN system_type_id IN (231, 239) THEN LTRIM(RTRIM(CONVERT(NVARCHAR(max),hex_Value))) --NVARCHAR ,NCHAR
WHEN system_type_id IN (167,175) THEN LTRIM(RTRIM(CONVERT(VARCHAR(max),hex_Value))) --VARCHAR,CHAR
WHEN system_type_id IN (35) THEN LTRIM(RTRIM(CONVERT(VARCHAR(max),hex_Value))) --Text
WHEN system_type_id IN (99) THEN LTRIM(RTRIM(CONVERT(NVARCHAR(max),hex_Value))) --nText
WHEN system_type_id = 48 THEN CONVERT(VARCHAR(MAX), CONVERT(TINYINT, CONVERT(BINARY(1), REVERSE (hex_Value)))) --TINY INTEGER
WHEN system_type_id = 52 THEN CONVERT(VARCHAR(MAX), CONVERT(SMALLINT, CONVERT(BINARY(2), REVERSE (hex_Value)))) --SMALL INTEGER
WHEN system_type_id = 56 THEN CONVERT(VARCHAR(MAX), CONVERT(INT, CONVERT(BINARY(4), REVERSE(hex_Value)))) -- INTEGER
WHEN system_type_id = 127 THEN CONVERT(VARCHAR(MAX), CONVERT(BIGINT, CONVERT(BINARY(8), REVERSE(hex_Value))))-- BIG INTEGER
WHEN system_type_id = 61 Then CONVERT(VARCHAR(MAX),CONVERT(DATETIME,CONVERT(VARBINARY(8000),REVERSE (hex_Value))),100) --DATETIME
WHEN system_type_id =58 Then CONVERT(VARCHAR(MAX),CONVERT(SMALLDATETIME,CONVERT(VARBINARY(8000),REVERSE(hex_Value))),100) --SMALL DATETIME
WHEN system_type_id = 108 THEN CONVERT(VARCHAR(MAX),CONVERT(NUMERIC(38,20), CONVERT(VARBINARY,CONVERT(VARBINARY(1),xprec)+CONVERT(VARBINARY(1),xscale))+CONVERT(VARBINARY(1),0) + hex_Value)) --- NUMERIC
WHEN system_type_id =106 THEN CONVERT(VARCHAR(MAX), CONVERT(DECIMAL(38,20), CONVERT(VARBINARY,Convert(VARBINARY(1),xprec)+CONVERT(VARBINARY(1),xscale))+CONVERT(VARBINARY(1),0) + hex_Value)) --- DECIMAL
WHEN system_type_id In(60,122) THEN CONVERT(VARCHAR(MAX),Convert(MONEY,Convert(VARBINARY(8000),Reverse(hex_Value))),2) --MONEY,SMALLMONEY
WHEN system_type_id = 104 THEN CONVERT(VARCHAR(MAX),CONVERT (BIT,CONVERT(BINARY(1), hex_Value)%2)) -- BIT
WHEN system_type_id =62 THEN RTRIM(LTRIM(STR(CONVERT(FLOAT,SIGN(CAST(CONVERT(VARBINARY(8000),Reverse(hex_Value)) AS BIGINT)) * (1.0 + (CAST(CONVERT(VARBINARY(8000),Reverse(hex_Value)) AS BIGINT) & 0x000FFFFFFFFFFFFF) * POWER(CAST(2 AS FLOAT), -52)) * POWER(CAST(2 AS FLOAT),((CAST(CONVERT(VARBINARY(8000),Reverse(hex_Value)) AS BIGINT) & 0x7ff0000000000000) / EXP(52 * LOG(2))-1023))),53,LEN(hex_Value)))) --- FLOAT
When system_type_id =59 THEN Left(LTRIM(STR(CAST(SIGN(CAST(Convert(VARBINARY(8000),REVERSE(hex_Value)) AS BIGINT))* (1.0 + (CAST(CONVERT(VARBINARY(8000),Reverse(hex_Value)) AS BIGINT) & 0x007FFFFF) * POWER(CAST(2 AS Real), -23)) * POWER(CAST(2 AS Real),(((CAST(CONVERT(VARBINARY(8000),Reverse(hex_Value)) AS INT) )& 0x7f800000)/ EXP(23 * LOG(2))-127))AS REAL),23,23)),8) --Real
WHEN system_type_id In (165,173) THEN (CASE WHEN CHARINDEX(0x,cast('' AS XML).value('xs:hexBinary(sql:column("hex_Value"))', 'VARBINARY(8000)')) = 0 THEN '0x' ELSE '' END) +cast('' AS XML).value('xs:hexBinary(sql:column("hex_Value"))', 'varchar(max)') -- BINARY,VARBINARY
WHEN system_type_id =34 THEN (CASE WHEN CHARINDEX(0x,cast('' AS XML).value('xs:hexBinary(sql:column("hex_Value"))', 'VARBINARY(8000)')) = 0 THEN '0x' ELSE '' END) +cast('' AS XML).value('xs:hexBinary(sql:column("hex_Value"))', 'varchar(max)') --IMAGE
WHEN system_type_id =36 THEN CONVERT(VARCHAR(MAX),CONVERT(UNIQUEIDENTIFIER,hex_Value)) --UNIQUEIDENTIFIER
WHEN system_type_id =231 THEN CONVERT(VARCHAR(MAX),CONVERT(sysname,hex_Value)) --SYSNAME
WHEN system_type_id =241 THEN CONVERT(VARCHAR(MAX),CONVERT(xml,hex_Value)) --XML
WHEN system_type_id =189 THEN (CASE WHEN CHARINDEX(0x,cast('' AS XML).value('xs:hexBinary(sql:column("hex_Value"))', 'VARBINARY(8000)')) = 0 THEN '0x' ELSE '' END) +cast('' AS XML).value('xs:hexBinary(sql:column("hex_Value"))', 'varchar(max)') --TIMESTAMP
WHEN system_type_id=98 THEN (CASE
WHEN CONVERT(INT,SUBSTRING(hex_Value,1,1))=56 THEN CONVERT(VARCHAR(MAX), CONVERT(INT, CONVERT(BINARY(4), REVERSE(Substring(hex_Value,3,Len(hex_Value)))))) -- INTEGER
WHEN CONVERT(INT,SUBSTRING(hex_Value,1,1))=108 THEN CONVERT(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)))) --- NUMERIC
WHEN CONVERT(INT,SUBSTRING(hex_Value,1,1))=167 THEN LTRIM(RTRIM(CONVERT(VARCHAR(max),Substring(hex_Value,9,Len(hex_Value))))) --VARCHAR,CHAR
WHEN CONVERT(INT,SUBSTRING(hex_Value,1,1))=36 THEN CONVERT(VARCHAR(MAX),CONVERT(UNIQUEIDENTIFIER,Substring((hex_Value),3,20))) --UNIQUEIDENTIFIER
WHEN CONVERT(INT,SUBSTRING(hex_Value,1,1))=61 THEN CONVERT(VARCHAR(MAX),CONVERT(DATETIME,CONVERT(VARBINARY(8000),REVERSE (Substring(hex_Value,3,LEN(hex_Value)) ))),100) --DATETIME
WHEN CONVERT(INT,SUBSTRING(hex_Value,1,1))=165 THEN '0x'+ SUBSTRING((CASE WHEN CHARINDEX(0x,cast('' AS XML).value('xs:hexBinary(sql:column("hex_Value"))', 'VARBINARY(8000)')) = 0 THEN '0x' ELSE '' END) +cast('' AS XML).value('xs:hexBinary(sql:column("hex_Value"))', 'varchar(max)'),11,LEN(hex_Value)) -- BINARY,VARBINARY
END)
END AS FieldValue
,[Rowlogcontents]
,[Row ID]
FROM @ColumnNameAndData ORDER BY nullbit
--Create the column name in the same order to do pivot table.
DECLARE @FieldName VARCHAR(max)
SET @FieldName = STUFF(
(
SELECT ',' + CAST(QUOTENAME([Name]) AS VARCHAR(MAX)) FROM syscolumns WHERE id=object_id('' + @SchemaName_n_TableName + '')
FOR XML PATH('')), 1, 1, '')
--Finally did pivot table and get the data back in the same format.
SET @sql = 'SELECT ' + @FieldName + ' FROM #temp_Data PIVOT (Min([FieldValue]) FOR FieldName IN (' + @FieldName + ')) AS pvt'
EXEC sp_executesql @sql
GO
--Execute the procedure like
--Recover_Deleted_Data_Proc 'Database Name','Schema.table name'
--EXAMPLE #1 : FOR ALL DELETED RECORDS
EXEC Recover_Deleted_Data_Proc 'test','dbo.Test_table'
GO
--EXAMPLE #2 : FOR ANY SPECIFIC DATE RANGE
EXEC Recover_Deleted_Data_Proc 'test','dbo.Test_Table' ,'2011/12/01','2012/01/30'
--It will give you the result of all deleted records.
解释：
它是如何工作的？让我们一步一步地看一下。该过程需要七个简单的步骤：
步骤1：
我们需要从sql server中获取已删除的记录。通过使用标准的 SQL Server 函数fn_blog，我们可以轻松获取所有事务日志（包括已删除的数据）。但是，我们只需要从事务日志中选定的已删除记录。因此我们包含了三个过滤器（Context、Operation 和AllocUnitName）。
Context ('LCX_MARK_AS_GHOST'and 'LCX_HEAP')
Operation ('LOP_DELETE_ROWS')
AllocUnitName('dbo.Student') –- Schema + table Name这是代码片段：
Select [RowLog Contents 0]
FROM sys.fn_dblog(NULL,NULL)
WHERE AllocUnitName ='dbo.Student' AND Context IN ('LCX_MARK_AS_GHOST', 'LCX_HEAP')
AND Operation in ('LOP_DELETE_ROWS')
该查询将返回提供不同信息的列数，但我们只需要选择“RowLog content o”列，即可获取删除的数据。
列“ RowLog content 0”将如下所示：
“0x300018000100000000000000006B000056492020590000000500E001002800426F62206A65727279”
第2步：
现在，我们已经删除了数据，但是是十六进制值，但是 SQL 将这些数据保留在特定的顺序中，以便我们可以轻松地恢复它。但是在恢复数据之前，我们需要了解格式。这种格式在Kalen Delaney 的《SQL Internal》一书中有详细定义。
- 1 个字节：状态位 A
- 1 个字节：状态位 B
- 2 字节：固定长度大小
- n 字节：固定长度数据
- 2 字节：总列数
- n Bytes : NULL 位图（每列 1 位，1 表示该列为空，0 表示该列不为空）
- 2 字节：可变长度列的数量
- n 字节：列偏移数组（2x 可变长度列）
- n 字节：可变长度列的数据
因此，十六进制数据“ RowLog内容0”等于：
“状态位 A + 状态位 B + 固定长度大小 + 固定长度数据 + 总列数 + NULL 位图 + 变长列数 + NULL 位图 + 变长列数 + 列偏移数组 + 变长列数据”。
步骤3：
现在，我们需要将RowLog Content o（删除数据的十六进制值）分解为上面定义的结构。[颜色代码仅供参考]
- [固定长度数据] = 子字符串（ RowLog内容 0，状态位 A +状态位 B + 1,2 字节）
- [总列数] = 子字符串（ RowLog内容 0, [固定长度数据] + 1,2 字节）
- [空位图长度] = 上限（[总列数] /8.0）
- [空字节]=子字符串（RowLog内容0，状态位A+状态位B + [固定长度数据] +1，[空位图长度]）
- 变量列总数=子字符串（ RowLog内容0，状态位A+状态位B + [固定长度数据] +1， [空位图长度] +2）
- 列偏移数组= 子字符串（RowLog内容 0，状态位 A+ 状态位 B + [固定长度数据] +1，[空位图长度] + 2，变量列总数*2）
- 变量列起始 =状态位 A+ 状态位 B + [固定长度数据] + [空位图长度] + 2+(变量列总数*2)
步骤4：
现在，我们也有了数据的分割，因此我们可以通过使用Null Bytes来查找哪一列值为 null 或不是 null 。要实现此目的，请将空字节（十六进制值）转换为二进制格式（如上所述，1 表示该列为空，0 表示有一些数据）。在此数据中，空位图值为 00000111。我们只有五列学生表（用作样本），空位图的前五个值为 00000。这意味着没有空值。
步骤5：
现在，我们有了主要数据分割（步骤 3）和空值（步骤 4）。之后，我们需要使用此代码片段来获取列数据，如列名称、列大小、精度、小数位数，最重要的是叶空位（以确保列是固定数据（<=-1）或可变数据大小） (>=1)) 的表。
Select * from sys.allocation_units allocunits INNER JOIN sys.partitions分区ON ( allocunits . type IN ( 1 , 3 ) AND分区. hobt_id = allocunits .container_id ) OR ( allocunits . type = 2 AND分区.partition_id = allocunits .container_id ) INNER JOIN sys.system_internals_partition_columns cols ON cols 。 partition_id =分区. partition_id LEFT OUTER JOIN syscolumns ON syscolumns 。 id =分区。object_id和syscolumns 。柯里德=柯斯.分区列id
并根据allocunits.[Allocation_Unit_Id]将其与我们收集的数据表（Step-1,2,3,4）连接起来。到目前为止，我们已经知道了表和数据的信息，因此我们需要利用这些数据将 [ RowLog Contents 0] 分解为表列数据，但为十六进制值。这里我们需要小心，因为数据要么是固定列大小，要么是可变列大小。 。
步骤6：
我们收集了每列的十六进制数据（第 5 步）。现在我们需要根据定义为 [ System_type_id ] 的数据类型转换数据。每种类型都有不同的 数据转换机制。
步骤7：
最后，我们对数据进行数据透视表，您将看到结果。删除的数据又回来了。
注：此数据仅供展示。它在您选择的表中不可用，但您可以将此数据插入到表中。
update:
下面内容来源
https://www.cnblogs.com/lyhabc/p/3683147.html
支持date类型 感谢园友 dwchaoyue
EXEC Recover_Deleted_Data_Proc 'sss','dbo.testdaterecover','2014-04-23','2014-10-23'
--DROP TABLE testdaterecover
CREATE TABLE testdaterecover(dd DATE,cc DATETIME)
GO
INSERT INTO [dbo].[testdaterecover]
( [dd], [cc] )
VALUES ( GETDATE(), -- dd - date
GETDATE() -- cc - datetime
)
SELECT CONVERT(VARCHAR(MAX),CONVERT(DATETIME, CONVERT(VARBINARY(8000),[cc])),120) FROM [dbo].[testdaterecover]
DELETE [dbo].[testdaterecover]
THEN CONVERT(VARCHAR(MAX), CONVERT(DATETIME, CONVERT(VARBINARY(8000), REVERSE(hex_Value))), 121) --DATETIME其它一些注意的地方，都可以参考上面的这篇博文。
本文系外文翻译，前往查看
如有侵权，请联系 cloudcommunity@tencent.com 删除。
本文系外文翻译，前往查看
如有侵权，请联系 cloudcommunity@tencent.com 删除。
评论
登录后参与评论
推荐阅读
相关产品与服务
云数据库 SQL Server
腾讯云数据库 SQL Server （TencentDB for SQL Server）是业界最常用的商用数据库之一，对基于 Windows 架构的应用程序具有完美的支持。TencentDB for SQL Server 拥有微软正版授权，可持续为用户提供最新的功能，避免未授权使用软件的风险。具有即开即用、稳定可靠、安全运行、弹性扩缩等特点。