SQLSERVER 拯救 某个 时间 点被误 删除 的 数据 http://blog.csdn.net/dba_huangzj/article/details/8491327 要 拯救 某个 时间 点被误 删除 的 数据 ，需要你在那个 时间 点之前有一个完整 数据 库备份。 而且，需要你的 数据 库恢复模式为：完整恢复模式
SQLSERVER拯救某个时间点被误删除的数据
http://blog.csdn.net/dba_huangzj/article/details/8491327
要拯救某个时间点被误删除的数据，需要你在那个时间点之前有一个完整数据库备份。
而且，需要你的数据库恢复模式为：“完整恢复模式”
如何查看你的数据库恢复模式为完整恢复模式，运行下面SQL
<span>1</span> <span>SELECT</span><span> recovery_model, recovery_model_desc </span><span>2</span> <span>FROM</span><span> sys.databases </span><span>3</span> <span>WHERE</span> name <span>=</span> <span>'</span><span>GPOSDB</span><span>'</span>
在创建完一个新数据库之后，强烈建议做一次数据库完整备份
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先创建测试表
<span> 1</span> <span>/*</span> <span> 2</span> <span>由于tempdb永远为简单恢复模式，所以不适合做案例。 </span><span> 3</span> <span>这里使用我的测试机器里的<strong>数据</strong>库GPOSDB </span><span> 4</span> <span>*/</span> <span> 5</span> <span>USE</span> <span>[</span><span>GPOSDB</span><span>]</span> <span> 6</span> <span>GO</span> <span> 7</span> <span>IF</span> <span>OBJECT_ID</span>(<span>'</span><span>testRestore</span><span>'</span>) <span>IS</span> <span>NOT</span> <span>NULL</span> <span> 8</span> <span>DROP</span> <span>TABLE</span><span> testRestore </span><span> 9</span> <span>GO</span> <span>10</span> <span>CREATE</span> <span>TABLE</span><span> testRestore </span><span>11</span> <span> ( </span><span>12</span> id <span>INT</span> <span>IDENTITY</span>(<span>1</span>, <span>1</span><span>) , </span><span>13</span> NAME <span>VARCHAR</span>(<span>50</span><span>) </span><span>14</span> );
插入测试数据
<span> 1</span> <span>--</span><span>插入测试<strong>数据</strong>： </span> <span> 2</span> <span>INSERT</span> <span>INTO</span><span> testRestore(Name) </span><span> 3</span> <span>SELECT</span> <span>'</span><span>test1</span><span>'</span> <span> 4</span> <span>UNION</span> <span>ALL</span> <span> 5</span> <span>SELECT</span> <span>'</span><span>test2</span><span>'</span> <span> 6</span> <span>UNION</span> <span>ALL</span> <span> 7</span> <span>SELECT</span> <span>'</span><span>test3</span><span>'</span> <span> 8</span> <span>UNION</span> <span>ALL</span> <span> 9</span> <span>SELECT</span> <span>'</span><span>test4</span><span>'</span> <span>10</span> <span>UNION</span> <span>ALL</span> <span>11</span> <span>SELECT</span> <span>'</span><span>test5</span><span>'</span> <span>12</span> <span>UNION</span> <span>ALL</span> <span>13</span> <span>SELECT</span> <span>'</span><span>test6</span><span>'</span> <span>14</span> <span>UNION</span> <span>ALL</span> <span>15</span> <span>SELECT</span> <span>'</span><span>test7</span><span>'</span> <span>16</span> <span>UNION</span> <span>ALL</span> <span>17</span> <span>SELECT</span> <span>'</span><span>test8</span><span>'</span>
<span>1</span> <span>SELECT</span> <span>*</span> <span>FROM</span> testRestore
先来一个数据库完整备份，在22:32的时候完整备份数据库
<span>1</span> <span>BACKUP</span> <span>DATABASE</span> <span>[</span><span>GPOSDB</span><span>]</span> <span>2</span> <span>TO</span> <span>DISK</span><span>=</span><span>'</span><span>D:\GPOSDB_FULLBACKUP2013-07-23.bak</span><span>'</span> <span>3</span> <span>WITH</span><span> INIT </span><span>4</span> <span>go</span>
模拟删除表数据，这里使用waitfor time，目的是使删除数据的时间准确一点，这里选择22:34的时候删除数据方便后面还原某个时间点之前的数据
<span>1</span> <span>USE</span> <span>[</span><span>GPOSDB</span><span>]</span> <span>2</span> <span>GO</span> <span>3</span> <span>WAITFOR</span> TIME <span>'</span><span>22:34</span><span>'</span> <span>4</span> <span>DELETE</span> <span>FROM</span> dbo.testRestore
查询一下数据是否删除
<span>1</span> <span>USE</span> <span>[</span><span>GPOSDB</span><span>]</span> <span>2</span> <span>GO</span> <span>3</span> <span>SELECT</span> <span>*</span> <span>FROM</span> dbo.testRestore
断开与GPOSDB数据库的连接，如果还有连接就kill掉连接，然后执行事务日志备份，在22:36的时候执行事务日志备份
<span> 1</span> <span>--</span><span><strong>删除</strong>了表中的<strong>数据</strong>之后最少要等3分钟才执行下面SQL语句，不然的话等一下还原事务日志的时候会报错</span> <span> 2</span> <span>--</span><span>必须断开所有与GPOSDB<strong>数据</strong>库的连接</span> <span> 3</span> <span>USE</span><span> master </span><span> 4</span> <span>GO</span> <span> 5</span> <span>BACKUP</span> <span>LOG</span> <span>[</span><span>GPOSDB</span><span>]</span> <span>TO</span> <span>DISK</span> <span>=</span> N<span>'</span><span>D:\GPOSDB_LOGBACKUP2013-07-23.bak</span><span>'</span> <span>WITH</span> NO_TRUNCATE , NOFORMAT, NAME <span>=</span> N<span>'</span><span>GPOSDB-事务日志备份</span><span>'</span>, SKIP, NORECOVERY , STATS <span>=</span> <span>10</span><span>, CHECKSUM </span><span> 6</span> <span>GO</span> <span> 7</span> <span>DECLARE</span> <span>@backupSetId</span> <span>AS</span> <span>INT</span> <span> 8</span> <span>SELECT</span> <span>@backupSetId</span> <span>=</span><span> position </span><span> 9</span> <span>FROM</span><span> msdb..backupset </span><span>10</span> <span>WHERE</span> database_name <span>=</span> N<span>'</span><span>GPOSDB</span><span>'</span> <span>AND</span> backup_set_id <span>=</span> ( <span>SELECT</span> <span>11</span> <span>MAX</span><span>(backup_set_id) </span><span>12</span> <span>FROM</span><span> msdb..backupset </span><span>13</span> <span>WHERE</span> database_name <span>=</span> N<span>'</span><span>GPOSDB</span><span>'</span> <span>14</span> <span> ) </span><span>15</span> <span>IF</span> <span>@backupSetId</span> <span>IS</span> <span>NULL</span> <span>--</span><span>这里是验证事务日志备份是否成功，如果没有断开与GPOSDB<strong>数据</strong>库的连接备份事务日志可能会失败</span> <span>16</span> <span>BEGIN</span> <span>17</span> <span>RAISERROR</span>(N<span>'</span><span>验证失败。找不到<strong>数据</strong>库“GPOSDB”的备份信息。</span><span>'</span>, <span>16</span>, <span>1</span><span>) </span><span>18</span> <span>END</span> <span>19</span> <span>RESTORE</span> VERIFYONLY <span>FROM</span> <span>DISK</span> <span>=</span> N<span>'</span><span>D:\GPOSDB_LOGBACKUP2013-07-23.bak</span><span>'</span> <span>WITH</span> <span>FILE</span> <span>=</span> <span>@backupSetId</span> <span>20</span> <span>GO</span>
<span>1</span> <span>--</span><span>查询是否备份成功</span> <span>2</span> <span>SELECT</span> <span>TOP</span> <span>10</span> <span>*</span> <span>FROM</span> msdb..backupset <span>ORDER</span> <span>BY</span> <span>[</span><span>backup_set_id</span><span>]</span> <span>DESC</span>
还原数据库完整备份
<span>1</span> <span>--</span><span><strong>数据</strong>库处于正在还原状态</span> <span>2</span> <span>RESTORE</span> <span>DATABASE</span> <span>[</span><span>GPOSDB</span><span>]</span> <span>FROM</span> <span>DISK</span><span>=</span><span>'</span><span>D:\GPOSDB_FULLBACKUP2013-07-23.bak</span><span>'</span> <span>WITH</span> <span>replace</span>, NORECOVERY
还原事务日志
<span>1</span> <span>--</span><span>因为<strong>删除</strong><strong>数据</strong>是在'22:34' 所以还原到22:33</span> <span>2</span> <span>RESTORE</span> <span>LOG</span> <span>[</span><span>GPOSDB</span><span>]</span> <span>FROM</span> <span>DISK</span><span>=</span><span>'</span><span>D:\GPOSDB_LOGBACKUP2013-07-23.bak</span><span>'</span> <span>WITH</span> RECOVERY ,STOPAT<span>=</span><span>'</span><span>2013-7-23 22:33</span><span>'</span>
如果事务日志还原失败的话，可以使用GUI界面
查看表中的数据
<span>1</span> <span>USE</span> <span>[</span><span>GPOSDB</span><span>]</span> <span>2</span> <span>GO</span> <span>3</span> <span>SELECT</span> <span>*</span> <span>FROM</span> dbo.testRestore
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要注意的两个地方：
（1）如果你发现误操作以后还有很多人做了操作，那么你还原成功后，别人的操作就会冲掉，所以发生误操作后，要马上停止别人对数据库的操作。
（2）这个方法要对数据库独占
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