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Use DBCC SQLPerf (logspace) to monitor and optimize database performance in SQL Server. Would you want to know how to use DBCC SQLPerf (logspace)? Check all the details in below article:
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Data Recovery : Page level restore in SQL Server
Data Recovery : Page level restore in SQL Server
In this article, we shall discuss the importance of understanding the internals of the page restoration for a database administrator. Most of the time, performing a page-level restore suffices for database availability. A good backup strategy is a key to recovery or restoration, and SQL Server provides us with an option to fix database pages at a granular level. Performing a page level restore in…
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Sql Server Error - a Quick Overview
Why Almost Everything You've Learned About Sql Server Error Is Wrong
In case the query touches less data it'll be less inclined to encounter the issue. Problem is going to be resolved after following the above mentioned measures. The issue needs to be resolved. The issue with the error log file is that there's so much data collected it is occasionally tough to figure out where the real errors lie.
Everything beyond is thought of as an error To have the ability to use an apostrophe in a string, it must be escaped, so that it's not regarded as a string delimiter. Occasionally you will notice an error stating that the database can't be recovered and it's marked suspect. For example, the next error points out that we would have to restore our database or endeavor to rebuild the log. Now it doesn't even wish to me register and throwing the exact same 18452 error. In the event the above mentioned manual solutions to repair the error do not do the job, then it may be that the database may have corrupt. If you come across a severity 22 error, you'll need to run DBCC CHECKDB to figure out the magnitude of the damage.
Now you're seeing errors on-screen, but in a manufacturing environment, you don't acquire such flexibility. The error can be encountered at the right time of upgrading SQL server to some other version. Accordingly, so as to receive your critical data back, you will need to understand how to fix SQL server error 823. The error that's captured in the SQL Server error log can be a result of different factors. The error 823 can cause severe data loss circumstances. SetWindowText returns success and there's no runtime error, but the text doesn't appear. All the data are kept in a database in the shape of MDF and NDF files. In addition, it is going to continue to keep the data safe means with no loss. The real data is stored in the remaining part of the pages.
The Chronicles of Sql Server Error
You should inspect the error log daily to make sure that all prospective issues are investigated as speedily as possible. Also by default, the latest error log is named ERRORLOG and it does not have any extension. The very first step to receive it resolve is to look at the SQL Server error log.
The Argument About Sql Server Error
Make it part of your routine database maintenance. SQL Server service was paused. It is trying to intialize SSL support but it cannot find the requisite information.
Sql Server Error - What Is It?
Your default database may be missing. When a query is run, SQL attempts to allocate the optimum quantity of memory in order for it to run efficiently. Thus, for optimum compatibility, it's suggested that you use anytime you run queries returning more than 1 result even if the specific driver you're using allows you to do otherwise. System databases are made automatically if we install MS SQL Server. When seeking to log in, the database might not be prepared to accept the connection. The entire database will be impacted.
The server wasn't found or wasn't accessible. It enables easy storage and retrieval of data from application running on the same computer or other computers residing in the same network. SQLEXPRESS'' folders, you have to install SQL Server. SQL Server deliberately hides the character of the authentication error and provides State 1. It cannot roll committed transactions forward because it has no room on the disk. Begin your SQL Server instance and you may then connect to SQL Server utilizing the SA login.
In MS SQL Server, two forms of databases are readily available. Testdb database is going to be created as shown in the subsequent snapshot. Therefore, backing up database regularly is a great practice that aids in restoring data is true of disaster. The AdventureWorks 2014 sample database is utilized via the report.
New Questions About Sql Server Error
If you are working to connect using Windows Authentication, verify that you're properly logged into the proper domain. Your login may not be authorized to connect. The login was created. It failed for user is one of the most common error which everyone might have seen at least once. As a consequence the user doesn't have permission to use SQL database. Therefore, users are continuously querying about the reason for the same i.e. exact cause of the SQL Server operating system error 3. So, they will understand the causes and prevent Server from the future disaster.
You're unlikely ever to should alter the processor affinity defaults if you don't encounter performance issues but it's still worthwhile understanding what they are and the way in which they work. A Unix socket file is used if you don't specify a host name or whenever you Sql Server Error specify the particular host name localhost. Since you can see above that LOG folder consists of many files. The absolute most current error log file is known as ERRORLOG.
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ACPM 1st Batch (Advanced Certificate in Project Management) is only BDT 800.
ACPM কোর্স PMBoK Guide এর আদলে সাজানো হয়েছে।মাত্র ৮০০ টাকায় করে নিতে পারেন আপনার কাঙ্খিত কোর্স। সময় লাগবে ০১ মাস। মোট ১০ টি মডিউল থাকবে। এসাইনমেন্টভিত্তিক এসেসমেন্ট।
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When your first 2 weeks on the job includes fun with SQL Server Enterprise Manager, DBCC IND and DBCC Page... in that order.
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How SQL Stores Data Internally - SQL 8KB Page | SQL Data Page | SQL IAM Page | SQL Index Page
Q01. What is the 8KB page concept of SQL? Q02. What is Extent in SQL? Q03. What is Page Split in SQL? When does a page split happen? Q04. What is Fragmentation in SQL? Q05. How does SQL Server store the data internally? Q06. What are Page Header and Row Offset in SQL? Q07. What is IAM Page in SQL? How many IAM pages can be there for a table? Q08. Why the max size of the VARCHAR data type is only 8000? Q09. Why the max size of the NVARCHAR data type is only 4000? Q10. How a VARCHAR(MAX) or NVARCHAR(Max) data stores on the 8KB page? Q11. Why index can not be created on VARCHAR(MAX) or NVARCHAR(Max) data type columns? Q12. What is the maximum data row size that can be stored in a single page? Q13. What is the In-row page mean? Q14. What is the DBCC IND SQL command? Q15. What is the DBCC PAGE SQL command?
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New Post has been published on SONGWRITER NEWS
New Post has been published on https://songwriternews.co.uk/2021/05/nexus-six-feat-dick-reckard/
Nexus Six (feat. Dick Reckard)
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Migrating SQL Server to Amazon RDS using native backup and restore
Running Microsoft SQL Server on Amazon Relational Database Service (Amazon RDS) automates time-consuming administration tasks such as installation, disk provisioning and management, patching, minor and major version upgrades, and backup and recovery of your SQL Server databases. Amazon RDS also offers high availability using a Multi-AZ solution, replicating data synchronously across different Availability Zones. Currently, you can migrate self-managed SQL server to Amazon RDS for SQL Server using any of the following methods: Using AWS Database Migration Service (AWS DMS). For more information, see Migrating your SQL Server database to Amazon RDS for SQL Server using AWS DMS Using SQL Server transactional replication. For more information, see migrate to Amazon RDS for SQL Server using transactional replication Using SQL Server backup and restore features In this post, we demonstrate how to use the SQL Server backup and restore features to migrate to Amazon RDS for SQL Server. This involves performing a full backup followed by differential and log backups on the source instance and restoring the same backups to the target RDS for SQL Server instance. With the help of differential and log backup, we significantly reduce application cutover time during the migration process. On Amazon RDS for SQL Server, the native backup and restore functionality is supported with the help of stored procedures. For this post, we use a self-managed SQL Server database that runs on the following backup schedule: Full backup every Saturday at 9:00 PM Differential backup every 4 hours Transaction log backup every 30 mins The following diagram illustrates this architecture. The migration process can be described with the following high-level steps: Restore a full backup to Amazon RDS for SQL Server. Restore a differential backup to Amazon RDS for SQL Server. Because differential backups are cumulative, we restore the most recent differential backup since the last full backup. Restore subsequent transaction log backups to the latest point in time. Validate and cut over. As of this writing, differential and log restores are not supported on Multi-AZ instances. We suggest creating a single Availability Zone RDS instance for migration purposes and modifying it to Multi-AZ at a later point. Restoring a full backup to Amazon RDS for SQL Server The backup files need to be in Amazon Simple Storage Service (Amazon S3) so they can be restored on Amazon RDS for SQL Server. To copy the files to Amazon S3, use the Amazon S3 console or the AWS Command Line Interface (AWS CLI). When the files are available on Amazon S3, you create an AWS Identity and Access Management (IAM) role to provide Amazon RDS access to the S3 bucket with the backup files. Creating an IAM policy and role We have included a sample policy in this post for reference. Create a new role with this policy and add trust for Amazon RDS to assume this role. { "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": [ "s3:ListBucket", "s3:GetBucketLocation" ], "Resource": "arn:aws:s3:::bucket_name" }, { "Effect": "Allow", "Action": [ "s3:GetObject", "s3:PutObject", "s3:ListMultipartUploadParts", "s3:AbortMultipartUpload" ], "Resource": "arn:aws:s3:::bucket_name/*" } ] } Adding trust for Amazon RDS to assume the role When you create an IAM role, you attach a trust relationship and a permissions policy. The trust relationship allows Amazon RDS to assume this role. See the following code: { "Version": "2012-10-17", "Statement": [{ "Effect": "Allow", "Principal": {"Service": "rds.amazonaws.com"}, "Action": "sts:AssumeRole" }] } Adding an option group for backup and restore Option groups in Amazon RDS provide flexibility to manage additional features. In this post, we add an option for native backup and restore. For a full list of available options, see Options for the Microsoft SQL Server database engine. You can create a new option group if it doesn’t exist and then add an option SQLSERVER_BACKUP_RESTORE to that option group. Complete the following steps: On the Amazon RDS console, choose Option Groups in the navigation pane. Choose Create Group. Enter the name, description, engine, and engine version of your server. Choose Create. Select the option group that you created, and choose Add Option. Choose SQLSERVER_BACKUP_RESTORE. Choose the IAM Role created in the earlier step. Choose Immediately. Choose Add Option. Associate the option group with the DB instance by choosing Databases in the navigation pane. Choose the target RDS SQL Server instance On the Actions menu, choose Modify. Under Database Options, choose the option group that you created. Choose Continue. Choose Apply Immediately. Review the information and choose Modify DB Instance. This option group modification has no downtime because an instance reboot is not required. Restoring the full backup to Amazon RDS After setting up the IAM role and option group, you can start the restore process. With the backup schedule scenario defined earlier, this is a backup taken on Saturday at 9:00 PM. Amazon S3 has a size limit of 5 TB per file. For native backups of larger databases, you can use a multi-file backup on the source instance. Run the following Amazon RDS restore procedures in SQL Server Management Studio: use master go exec msdb.dbo.rds_restore_database @restore_db_name='mydatabase', @s3_arn_to_restore_from='arn:aws:s3:::bucketname/sqlserverbackups/mydb_full-1.bak', @with_norecovery=1, @type='FULL'; go The preceding restore task uses the NORECOVERY option by specifying @with_norecovery=1. The database is left in the RESTORING state, allowing for subsequent differential or log restores. You can check the status of the restore task with the following code: use master go select * from msdb.dbo.rds_fn_task_status(null,0) go The restore process is complete when the lifecycle shows SUCCESS and percentage complete is 100. Restoring differential backups to Amazon RDS for SQL Server Differential backups have all the changes since the last full backup. Because differential backups are cumulative, use the latest differential backup file to restore. For our use case, we use a differential backup that was taken Sunday at 5:00 AM. See the following code: use master go exec msdb.dbo.rds_restore_database @restore_db_name='mydatabase', @s3_arn_to_restore_from='arn:aws:s3:::bucketname/sqlserverbackups/mydb_diff-1.bak', @type='DIFFERENTIAL', @with_norecovery=1; go Restoring subsequent transaction log backups to Amazon RDS for SQL Server Transaction logs record all the database modifications made by each transaction. You must create at least one full backup before you can create any log backups. The sequence of transaction log backups (called a log chain) is independent of data backups. If you want to restore a database to a certain point, restore the full backup followed by the latest differential backup and all subsequent transaction logs up to that restore point. For our use case, we restore the differential backup taken Sunday at 5:00 AM, so we need to restore all transaction log backups taken after 5:00 AM. We must apply log backups in the sequence in which they were created, without any gaps in the log chain. To minimize the cutover time, you may want to consider taking one final manual log backup. Restore all the log backups except the last one by specifying @with_norecovery=1: use master go exec msdb.dbo.rds_restore_log @restore_db_name='mydatabase', @s3_arn_to_restore_from='arn:aws:s3:::bucketname/sqlserverbackup/mydb_log_n.trn', @with_norecovery=1; go Before running a final log backup on the source database, issue a checkpoint to persist data pages located in the buffer pool to database files. Also, while making a final log backup, update the status of the source database to be read-only to avoid any database changes on the source instance during cutover. Ensure there are no active transactions using DBCC OPENTRAN. See the following code: -- source database GO ALTER DATABASE source_database SET SINGLE_USER WITH ROLLBACK IMMEDIATE GO ALTER DATABASE source_database SET READ_ONLY WITH ROLLBACK IMMEDIATE GO ALTER DATABASE source_database SET MULTI_USER GO When the database in read-only mode, we proceed with the final log backup on the source instance and restore it on Amazon RDS for SQL Server: use master go exec msdb.dbo.rds_restore_log @restore_db_name='mydatabase', @s3_arn_to_restore_from='arn:aws:s3:::bucketname/sqlserverbackup/mydb_log_final.trn', @with_norecovery=0; go We restore the final log backup by specifying @with_norecovery=0. This brings the database state to online after the restore task completion. Validating and cutting over In the target RDS instance, check if all restore tasks completed successfully in Amazon RDS SQL for Server: use master go select * from msdb.dbo.rds_fn_task_status(null,0) go The following screenshot shows the results. Additionally, you can build in data validation to compare record count and data records between the source and target for key tables using linked servers. For instructions, see Implement Linked Servers with Amazon RDS for Microsoft SQL Server. After successfully completing restore tasks and data validation, modify the RDS instance to enable Multi-AZ. When this is complete, update the endpoint in the application to point to the RDS for SQL Server instance. This completes the migration process to Amazon RDS for SQL Server. Summary This post covered how to migrate self-managed SQL Server to Amazon RDS for SQL Server using native backup and restore functionality. With a successful migration to Amazon RDS, you can focus on what matters to your organization’s business, such as optimizing database design, capacity sizing, and performance tuning. If you have any questions or suggestions, please leave us a comment. About the Authors Veerendra Nayak is a Senior Database Solution Architect with Amazon Web Services. Sam Selvan is a Senior Database Solution Architect with Amazon Web Services. https://aws.amazon.com/blogs/database/migrating-sql-server-to-amazon-rds-using-native-backup-and-restore/
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DBCC revises revenue, disbursement estimates – The Manila Times This screengrab shows Budget Secretary Wendel Avisado speaking during a Development Budget Coordination Committee briefing on Dec. 3, 2020. (Screengrab from the Department of Budget and Management Facebook page) The country’s economic manage... https://trendingph.net/dbcc-revises-revenue-disbursement-estimates-the-manila-times/?feed_id=30600&_unique_id=5fcc9a510a09b #dbcc #disbursement #estimates #manila #philippinenews #philippinesnews #revenue #revises #times #trendingph
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SQL Server 中的空值位图掩码（NULL bitmap mask），深入理解 SQL Server 中NULL值
前段时间公司的一些底层数据进行了调整和梳理，为了保证各个电商平台数据的统一性，我们对和我们对接的爬虫组定了很多对应的接口表，有一天突然有人问到我这样的问题：接口表里面的一些字段可能只在 ALI 、JD 等一些平台上有但在另外一些平台上是没有的，那这些平台对应接口表里面的这些字段都是空着的，每天那么多数据会不会占用大量的空间？
这是对 SQL Server 中NULL值 存储方式不了解导致的，空值位图掩码是在SQL Server 数据中列是否存储NULL值时存储引擎层进行的编码。它是一个简单的位图掩码，如果值是1的话，表示这列有NULL值，如果是0的话，表示这列有具体的值（非NULL值，包含空白值）。
首先看一张从网上偷来的一张数据行的组合结构图，它可以帮我们可以很清楚的理解存储引擎用来在磁盘上存储记录的结构。
这个格式被称为定长变量格式（FixedVar format），因为SQL Server总是先存储定长列（像INT，CHAR），再存储变长列（像VARCHAR)。从图中我们可以看到，SQL Server以存储2 bytes的状态位开始，接着用2 bytes存储由行头到定长列结尾长度（包含所有定长列数据）。然后用2 bytes存储列个数，紧随其他的就是真正的空值位图掩码（NULL bitmap mask）。
看完图你可能会问 ：为什么SQL Server在每条数据行里存储具体的列数？对于每条数据行，列数都不是一样的么？为什么SQL Server要存储这些冗余的数据？
第1个答案是非常简单和有逻辑性的：SQL Server需要列数来计算用作实际空值位图掩码（NULL bitmap mask）的字节数。小于等于8列的表需要1 byte，9到16列需要 2 bytes，17到24列需要3 bytes，以此类推。明白了么？但在表里每条记录的列数必须是一样的！
我们来看第2个用实例分析的技术性正确答案：首先，你要知道空值位图掩码（NULL bitmap mask）是用在数据引擎级别，即当前记录中的列数。这就是说SQL Server在物理行可以存储不同数量的列。额，好像说的有点含糊不清…………物理数据行列数和表元数据层（sys.dolumns）里列数并不一致。这些也是SQL Server内部的真正不同层级。
因此在什么情况下这些层级间会彼此不相等呢？很简单：当你往表里增加列的时候！如果你加的列是NULL还是NOT NULL，SQL Server会作出完全不同的区别。当你增加一个新的NULL列到表时，SQL Server只更新表元数据层，一点也不接触到存储引擎层。也就是说当你增加一个NULL列时，所有的记录物理存储上不发生任何改变。另一方面，当你增加一个NOT NULL列时，SQL Server会更新表元数据层，同时也会更新存储引擎层，这就是说，SQL Server会接触并重写表里的每一条记录，在那里你增加了一个NOT NULL列。这会带来性能上的巨大区别！因此SQL Server需要在每条数据记录里存储具体的列数，因为这里的列数不能和表元数据层的列数同步。
我们来拿具体的例子来详细分析下。这个例子我们创建了一个简单的含8列的表，SQL Server需要使用1 bytes来作为空值位图掩码（NULL bitmap mask）。
CREATE TABLE TestTable ( Column1 INT IDENTITY(1, 1) NOT NULL, Column2 CHAR(600) NOT NULL, Column3 CHAR(600) NOT NULL, Column4 CHAR(600) NOT NULL, Column5 CHAR(600) NOT NULL, Column6 VARCHAR(600) NOT NULL, Column7 VARCHAR(600) NOT NULL, Column8 VARCHAR(600) NOT NULL ) GO
然后，我们往表里插入2条记录:
INSERT INTO TestTable VALUES ( REPLICATE('2', 600), REPLICATE('3', 600), REPLICATE('4', 600), REPLICATE('5', 600), REPLICATE('6', 600), REPLICATE('7', 600), REPLICATE('8', 600) ), ( REPLICATE('2', 600), REPLICATE('3', 600), REPLICATE('4', 600), REPLICATE('5', 600), REPLICATE('6', 600), REPLICATE('7', 600), REPLICATE('8', 600) ) GO
我们通过DBCC PAGE命令查看下具体的数据页：
DBCC IND(ALLOCATIONDB, TestTable, -1) GO
DBCC TRACEON(3604) GO DBCC PAGE(ALLOCATIONDB, 1, 24993, 1) GO
DBCC TRACEON(3604) GO DBCC PAGE(ALLOCATIONDB, 1, 24995, 1) GO
可以看到，每条记录的长度是 4129 bytes（4204 bytes 数据+ 7 bytes 行开销+ 2 bytes 变长列个数 + 3 * 2 bytes 每个变长列结束位置的偏移量）。
现在我们往表里加一个新的NULL列：
ALTER TABLE TestTable ADD Column9 CHAR(600) NULL
GO
这是表里的第9列，也就是说SQL Server对于这个列数需要2 bytes。但是 SQL Server并不在存储引擎层改变物理数据行，因为我们只加了一个NULL列。SQL Server不需要在存储引擎层做任何处理。我们可以通过查看数据页来验证下：
记录还是同样4219 bytes的长度，但是我们逻辑上已经在表上加了1列。现在我们来更新表的1条记录，这样的话，新加列就有具体值了：
UPDATE TestTable SET Column9 = REPLICATE('9', 600) WHERE Column1 = 1 GO
当你查看表里第2条记录的数据页时，记录大小还是原来的4219 bytes。
DBCC TRACEON(3604) GO DBCC PAGE(ALLOCATIONDB, 1, 24995, 1) GO
你现在创建了一个场景：SQL Server在数据行内部存储了不同长度的空值位图掩码（NULL bitmap mask）。这就是说你有定长列的表，在存储引擎级别，却有不同长度的行大小！很有趣，是不是？
现在我们删除表并重建，继续往表里插入2条记录：
DROP TABLE dbo.TestTable
CREATE TABLE TestTable ( Column1 INT IDENTITY(1, 1) NOT NULL, Column2 CHAR(600) NOT NULL, Column3 CHAR(600) NOT NULL, Column4 CHAR(600) NOT NULL, Column5 CHAR(600) NOT NULL, Column6 VARCHAR(600) NOT NULL, Column7 VARCHAR(600) NOT NULL, Column8 VARCHAR(600) NOT NULL ) GO
INSERT INTO TestTable VALUES ( REPLICATE('2', 600), REPLICATE('3', 600), REPLICATE('4', 600), REPLICATE('5', 600), REPLICATE('6', 600), REPLICATE('7', 600), REPLICATE('8', 600) ), ( REPLICATE('2', 600), REPLICATE('3', 600), REPLICATE('4', 600), REPLICATE('5', 600), REPLICATE('6', 600), REPLICATE('7', 600), REPLICATE('8', 600) ) GO
现在我们往表里增加一个NOT NULL列：
ALTER TABLE TestTable ADD Column9 CHAR(600) NOT NULL DEFAULT REPLICATE('9', 600) GO
现在，SQL Server需要在存储引擎层改变每条记录，因为新列的默认值必须被增加（当你表里已经有记录存储时，新加列必须要定义一个默认值），而且SQL Server需要扩展空值位图掩码（NULL bitmap mask）。
DBCC IND(ALLOCATIONDB, TestTable, -1) GO
DBCC TRACEON(3604) GO DBCC PAGE(ALLOCATIONDB, 1, 24993, 1) GO
DBCC TRACEON(3604) GO DBCC PAGE(ALLOCATIONDB, 1, 24995, 1) GO
当你处理大表，给表增加NOT NULL列时，这个现象会导致严重的性能问题。想象下我们往表里插入100万条记录。当我们增加NULL列时，SQL Server只需要几毫秒，因为只进行元数据修改操作。但当我们往表里增加NOT NULL列时，SQL Server待ALTER TABLE操作完成需要花费40秒！在处理大表，往表里增加NOT NULL列，这的确是个非常严重的性能降级！！
希望你现在已经理解了为什么SQL Server在存储引擎层对每条记录存储具体的列数，还有在SQL Server里，当你往大表里增加NOT NULL列，会出现严重的性能问题。
参考文章：
https://www.sqlpassion.at/archive/2011/06/29/the-mystery-of-the-null-bitmap-mask/
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Eid e Miladunnabi may bring happiness, justice, prosperity and freedom for all.
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SQL Server - Reset the numeric counter (seed) of an Identity column
If you came across this article, you probably need to reset the numeric value (seed counter) of an identity column used by a table in your SQL Server database. The method described here works with all versions of SQL Server : SQL Server 2002, SQL Server 2005, SQL Server 2008, SQL Server 2008R2, SQL Server 2012, SQL Server 2014, SQL Server 2016, up to the most recent SQL Server 2017.
Arguments
table_name: Is the name of the table for which to check the current identity value. The table specified must contain an identity column. Table names must follow the rules for identifiers. Two or three part names must be delimited, such as 'Person.AddressType' or . NORESEED: Specifies that the current identity value shouldn't be changed. RESEED: Specifies that the current identity value should be changed. new_reseed_value: Is the new value to use as the current value of the identity column. WITH NO_INFOMSGS: Suppresses all informational messages.
Example
For example, the following command: Will reset to 1 the identity column value of Table1. Once executed, the command will output the following confirmation message: Identity information control: current Identity value '1', current column value '1. DBCC execution completed. If DBCC error messages were displayed, contact your system administrator.
References
If you need additional info, you can also take a look to the dedicated DBCC CHECKIDENT page available on the official SQL Server 2017 documentation. Read the full article
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DatabaseRestore: Open Source Database Restore Stored Procedure
Welcome to the DatabaseRestore documentation page.
We were looking for a script that restores a database including the transaction log chain using the backup files in a folder. We also wanted it to be able to continue applying transaction log backups. In other words, we were looking for a custom Log Shipping solution. We could roll our own, but why reinvent the wheel if something already exists? We tried a couple of scripts, but GregWhiteDBA‘s DatabaseRestore stored procedure fit our needs and didn’t need a lot of modifications.
DatabaseRestore is an MIT-licensed open-source stored procedure that restores backups that were created using Ola Hallengren‘s DatabaseBackup solution. Thanks GregWhiteDBA for making it open source! If you aren’t using Ola’s solution for your database backups, you could modify DatabaseRestore to support native backups or another backup solution. That exercise is left to the reader.
The following modifications were made to DatabaseRestore:
Removed code that assumed that the FULL backups are copy-only backups
Removed @BackupPath parameter and added @BackupPathFull and @BackupPathLog in case the files are stored in different base paths
Removed @LogToTable parameter as it wasn’t used in the code
Added @RunRecovery and @ContinueLogs in case the user needed to restore more LOG backups
Changed the data types of the input parameters to match system data types or to use the smallest data type
Added columns to the table variables that store the output of RESTORE FILELISTONLY and RESTORE HEADERONLY since SQL Server 2016 has more columns in the output
Added code to read the LSN information from the LOG backup and compare it to the LSN from the newest FULL backup so that it doesn’t fail when it tries to restore a LOG backup that is too early
Added code to read the LSN information from the restored database and compare it to the LSN from the LOG backups when @ContinueLogs = 1 so that it can figure out which LOG file to restore and not throw an error for the LOG backups that were already restored
Cleaned up the code to have consistency between upper and lower cases of variables
DatabaseRestore may fail if you are not using SQL Server 2016 due to the extra columns that were added to @Headers and @FileListParameters to support the new columns returned by RESTORE HEADERONLY and RESTORE FILELISTONLY commands. It’s a simple enough fix but is not included in our code at this time.
INPUT PARAMETERS
@Database NVARCHAR(128) – name of the source database
@RestoreDatabaseName NVARCHAR(128), default=NULL – name of the restored database, can leave off or set to NULL if the restored name will be the source database’s name
@BackupPathFull NVARCHAR(MAX) – full path with ending backslash where the FULL backups are stored
@BackupPathLog NVARCHAR(MAX) – full path with ending backslash where the LOG backups are stored
@MoveFiles BIT, default=0 – whether or not you want to use a different location for the database files than what was used on the source server, leave off or set to 0 if using the same path as the source
@MoveDataDrive NVARCHAR(260), default=NULL – new location for the data file(s), used when @MoveFiles=1
@MoveLogDrive NVARCHAR(260), default=NULL – new location for the log file, used when @MoveFiles=1
@TestRestore BIT, default=0 – whether or not you are testing restores, if set to 1 then it drops the database at the end
@RunCheckDB BIT, default=0 – whether or not you want it to run DBCC CHECKDB after the restore, it assumes you are using Ola’s DatabaseIntegrityCheck stored procedure
@ContinueLogs, default=0 – whether or not you are continuing to restore logs after the database has already been restored without recovering it
@RunRecovery BIT, default=0 – whether or not to recover the database (RESTORE DATABASE WITH RECOVERY so that it is now usable)
SAMPLE CALLS
Restore the newest FULL backup and all LOG backups and then recover the database so that it can be used:
EXEC dbo.DatabaseRestore @Database = 'LogShipMe', @BackupPathFull = 'D:\Backup\SQL2016PROD1A\LogShipMe\FULL\', @BackupPathLog = 'D:\Backup\SQL2016PROD1A\LogShipMe\LOG\', @ContinueLogs = 0, @RunRecovery = 1;
Restore the newest FULL backup and all LOG backups but keep it in the NORECOVERY state so that more LOG backups can be applied:
EXEC dbo.DatabaseRestore @Database = 'LogShipMe', @BackupPathFull = 'D:\Backup\SQL2016PROD1A\LogShipMe\FULL\', @BackupPathLog = 'D:\Backup\SQL2016PROD1A\LogShipMe\LOG\', @ContinueLogs = 0, @RunRecovery = 0;
Restore more LOG backups but keep it in the NORECOVERY state so that more LOG backups can be applied:
EXEC dbo.DatabaseRestore @Database = 'LogShipMe', @BackupPathFull = 'D:\Backup\SQL2016PROD1A\LogShipMe\FULL\', @BackupPathLog = 'D:\Backup\SQL2016PROD1A\LogShipMe\LOG\', @ContinueLogs = 1, @RunRecovery = 0;
Restore more LOG backups, if any, and then recover the database so that it can be used:
EXEC dbo.DatabaseRestore @Database = 'LogShipMe', @BackupPathFull = 'D:\Backup\SQL2016PROD1A\LogShipMe\FULL\', @BackupPathLog = 'D:\Backup\SQL2016PROD1A\LogShipMe\LOG\', @ContinueLogs = 1, @RunRecovery = 1;
To get your hands on DatabaseRestore, download our free First Responder Kit.
Brent says: and this week during Google Cloud Next, you’ll learn about the Google Compute Engine project where Tara used this script. Stay tuned…
Pick the next GroupBy session lineup: voting is open now.
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