If one or more transaction log files are missing, the log file is rebuilt. If the log files are available, the Database Engine uses those files instead of rebuilding the log files. This operation breaks the log backup chain. We recommend that a full database backup be performed after the operation is completed. For more information about attaching and detaching databases, see Database Detach and Attach.
The name can be a character or Unicode constant, or a regular or delimited identifier. For more information, see "Database Files and Filegroups" in the Remarks section.
Only one data file can be created on each raw partition. Data files should not be put on compressed file systems unless the files are read-only secondary files, or the database is read-only.
Log files should never be put on compressed file systems. The path up to the last folder must exist, and the last folder must not exist. When size is not supplied for the primary file, the Database Engine uses the size of the primary file in the model database.
When a secondary data file or log file is specified, but size is not specified for the file, the Database Engine makes the file 8 MB beginning with SQL Server The size specified for the primary file must be at least as large as the primary file of the model database. The default is MB. Specify a whole number; do not include a decimal. Size is an integer value. For values greater than , use larger units. It continues to grow until the disk is full. The size specified is rounded to the nearest 64 KB, and the minimum value is 64 KB.
Filegroup cannot be specified on a database snapshot. The name must comply with the rules for identifiers. For code samples that create a filegroup to store memory-optimized data, see Creating a Memory-Optimized Table and a Natively Compiled Stored Procedure. Database snapshot names must be unique within an instance of SQL Server and comply with the rules for identifiers.
For the snapshot to work, all the data files must be specified individually. However, log files are not allowed for database snapshots.
The snapshot and source database must be on the same instance. For more information, see Database Snapshots in the Remarks section. The master database should be backed up whenever a user database is created, modified, or dropped. Each database has an owner that can perform special activities in the database.
The owner is the user that creates the database. Some database features depend on features or capabilities present in the file system for full functionality of a database. Some examples of features that depend on file system feature set include:. Every database has at least two files, a primary file and a transaction log file , and at least one filegroup. A maximum of 32, files and 32, filegroups can be specified for each database. When you create a database, make the data files as large as possible based on the maximum amount of data you expect in the database.
A database snapshot is transactionally consistent with the source database as it existed at the time when the snapshot was created. A source database can have multiple snapshots. If creating a database snapshot fails, the snapshot becomes suspect and must be deleted. For more information, see Database Snapshots.
Several database options are automatically set whenever you create a database. All user-defined objects in the model database are copied to all newly created databases. You can add any objects, such as tables, views, stored procedures, data types, and so on, to the model database to be included in all newly created databases.
For example, the database option auto shrink is set to true in model and in any new databases you create. If you change the options in the model database, these new option settings are used in any new databases you create. Changing operations in the model database does not affect existing databases. You can use catalog views, system functions, and system stored procedures to return information about databases, files, and filegroups.
For more information, see System Views. To maintain control over disk use on an instance of SQL Server, permission to create databases is typically limited to a few login accounts. In SQL Server, certain permissions are set on the data and log files of each database. Rolling up multiple rows into a single row and column for SQL Server data.
How to tell what SQL Server versions you are running. Resolving could not open a connection to SQL Server errors. Ways to compare and find differences for SQL Server tables and data. Searching and finding a string value in all columns in a SQL Server table. Sergey Gigoyan is a database professional with more than 10 years of experience, with a focus on database design, development, performance tuning, optimization, high availability, BI and DW design.
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Privacy policy. When you bulk import into a SQL Server table or bulk export data from a table, you can use a format file to a flexible system for writing data files that requires little or no editing to comply with other data formats or to read data files from other software programs. However, we recommend that you use the XML syntax for new format files because they provide several advantages over non-XML format files.
The version of the bcp utility Bcp. For example, SQL Server This topic describes how to use the bcp utility to create a format file for a particular table. The format file is based on the data-type option specified -n , -c , -w ,or -N and the table or view delimiters. To use a bcp command to create a format file, specify the format argument and use nul instead of a data-file path. The format option also requires the -f option, such as:. To distinguish a non-XML format file, we recommend that you use.
This section contains the following examples that show how to use bcp commands to create a non-XML format file:. You can not use block blobs for SQL Server data files.
Use page blobs. Estimating the cost of using Azure Services is an important matter in the decision making and planning process. This also results in transaction costs per database file, such as. Use the information on the Azure Pricing page to help estimate the monthly costs associated with the use of Azure Storage and Azure Virtual Machines. For each container used by a data or a log file, create a SQL Server credential whose name matches the container path.
The following example assumes that an Azure storage container has been created, and a policy has been created with read, write, and list rights. Creating a policy on a container generates a SAS key, which is safe to keep unencrypted in memory and needed by SQL Server to access the blob files in the container. If there are any active references to data files in a container, attempts to delete the corresponding SQL Server credential fails.
When creating a container for the Azure Blob storage service, we recommend that you set the access to private. When you set the access to private, container and blob data can be read by the Azure account owner only.
When storing SQL Server database files in Azure Storage, you need to use a shared access signature, a URI that grants restricted access rights to containers, blobs, queues, and tables. By using a shared access signature, you can enable SQL Server to access resources in your storage account without sharing your Azure storage account key. In addition, we recommend that you continue implementing the traditional on-premises security practices for your databases.
Other types of blob storage such as block blobs or Azure Data Lake Storage are not supported. In the current release of this feature, storing FileStream data in Azure Storage is not supported. You can store FileStream data in a database that also contains data files stored in Azure Storage, but all FileStream data files must be stored on local storage.
Since the FileStream data must reside on local storage, it cannot be moved between machines using Azure Storage, therefore we recommend that you continue using the traditional techniques to move the data associated with FileStream between different machines. If a storage account is geo-replicated and a geo-failover happened, database corruption could occur. For capacity limitations, see Introduction to Blob storage. Always On availability groups are supported as long as you do not add new database files to the database on the primary replica.
If a database operation requires a new file to be created in the database on the primary replica, first disable availability groups in the secondary node. Then, perform the database operation on the database and backup the database in the primary replica.
Next, restore the database to the secondary replica. After you finish, re-enable Always On availability groups in the secondary node.
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