Microsoft Snapshot Viewer is a software program developed by Microsoft. The primary executable is named SNAPVIEW.EXE. The setup package is about 984.31 KB (1,007,935 bytes) when donwloaded. Relative to the overall usage of those who have this installed, most are running it on Windows 7 (SP1). Download snapshot viewer windows 7 32 bit for free. Photo & Graphics tools downloads - Snapshot Viewer for Microsoft Access by Microsoft and many more programs are available for instant and free download.
-->A database snapshot is a read-only, static view of a SQL Server database (the source database). The database snapshot is transactionally consistent with the source database as of the moment of the snapshot's creation. A database snapshot always resides on the same server instance as its source database. While database snapshots provide a read-only view of the data in the same state as when the snapshot was created, the size of the snapshot file grows as changes are made to the source database. For details, see the Feature Overview section below.
Multiple snapshots can exist on a given source database. Each database snapshot persists until it is explicitly dropped by the database owner.
Note
Database snapshots are unrelated to snapshot backups, snapshot isolation of transactions, or snapshot replication.
In this Topic:
Feature Overview
Database snapshots operate at the later in this topic.
If a source database becomes RECOVERY_PENDING, its database snapshots may become inaccessible. After the issue on the source database is resolved, however, its snapshots should become available again.
Reverting is unsupported for any NTFS read-only or NTFS compressed files in the database. Attempts to revert a database containing either of these types of filegroups will fail.
In a log shipping configuration, database snapshots can be created only on the primary database, not on a secondary database. If you switch roles between the primary server instance and a secondary server instance, you must drop all the database snapshots before you can set the primary database up as a secondary database.
Self immunity from damage for 3 turns.2. Seven knights best awakened heroes.
A database snapshot cannot be configured as a scalable shared database.
FILESTREAM filegroups are not supported by database snapshots. If FILESTREAM filegroups exist in a source database, they are marked as offline in its database snapshots, and the database snapshots cannot be used for reverting the database.
Note
A SELECT statement that is executed on a database snapshot must not specify a FILESTREAM column; otherwise, the following error message will be returned:
Could not continue scan with NOLOCK due to data movement.
When statistics on a read-only snapshot are missing or stale, the Database Engine creates and maintains temporary statistics in tempdb. For more information, see Statistics.
Disk Space Requirements
Database snapshots consume disk space. If a database snapshot runs out of disk space, it is marked as suspect and must be dropped. (The source database, however, is not affected; actions on it continue normally.) Compared to a full copy of a database, however, snapshots are highly space efficient. A snapshot requires only enough storage for the pages that change during its lifetime. Generally, snapshots are kept for a limited time, so their size is not a major concern.
The longer you keep a snapshot, however, the more likely it is to use up available space. The maximum size to which a sparse file can grow is the size of the corresponding source database file at the time of the snapshot creation. If a database snapshot runs out of disk space, it must be deleted (dropped).
Note
Except for file space, a database snapshot consumes roughly as many resources as a database.
Database Snapshots with Offline Filegroups
Offline filegroups in the source database affect database snapshots when you try to do any of the following:
- Create a snapshotWhen a source database has one or more offline filegroups, snapshot creation succeeds with the filegroups offline. Sparse files are not created for the offline filegroups.
- Take a filegroup offlineYou can take a file offline in the source database. However, the filegroup remains online in database snapshots if it was online when the snapshot was created. If the queried data has changed since snapshot creation, the original data page will be accessible in the snapshot. However, queries that use the snapshot to access unmodified data in the filegroup are likely to fail with input/output (I/O) errors.
- Bring a filegroup onlineYou cannot bring a filegroup online in a database that has any database snapshots. If a filegroup is offline at the time of snapshot creation or is taken offline while a database snapshot exists, the filegroup remains offline. This is because bringing a file back online involves restoring it, which is not possible if a database snapshot exists on the database.
- Revert the source database to the snapshotReverting a source database to a database snapshot requires that all of the filegroups are online except for filegroups that were offline when the snapshot was created.
Related Tasks
See Also
DIT Snapshot Viewer is an inspection tool for Active Directory database, ntds.dit. This tool connects to ESE (Extensible Storage Engine) and reads tables/records including hidden objects by low level C API.
The tool can extract ntds.dit file without stopping lsass.exe. When Active Directory Service is running, lsass.exe locks the file and does not allow to access to it. The snapshot wizard copies ntds.dit using VSS (Volume Shadow Copy Service) even if the file is exclusively locked. As copying ntds.dit may cause data inconsistency in ESE DB, the wizard automatically runs esentutil /repair command to fix the inconsistency.
The executable is available here.Download ditsnap.exe
Screenshots
Main Window
Detail Dialog
Interpreted Value
Interpreted Value column in Detail Dialog shows human-readable representaions of raw ESE column values. Here are the exmamples.
OBJECT_CATEGORY
The attribute is stored as a 32-bit integer in ESE, which points to DNT (Distinguished Name Tag) of another Active Directory object. Interpreted Value for the attribute shows RDN (Relative Distinguished Name) of the object.
OBJECT_CLASS
The attribute is stored as a multi-valued 32-bit integer column in ESE, which points to GOVERNS_ID of other objects. Interpreted Value for the attribute shows RDNs of the objects.
PWD_LAST_SET, LAST_LOGON, LAST_LOGOFF, ACCOUNT_EXPIRES
Those attributes are stored as 64-bit integers in ESE, which are treated as FILETIME in Active Directory. Interpreted Value column for the attributes shows it as a date format.
WHEN_CREATED, WHEN_CHANGED
Those attributes are stored as 64-bit integers in ESE, which are treated as shortened FILETIME (1/10000000 of the integer representation of FILETIME). Interpreted Value for those attributes shows it as a date format.
USER_ACCOUNT_CONTROL
The attribute is stored as a 32-bit integer in ESE, which are treated as flags that control the behavior of the user account. Interpreted Value for the attribute shows the list of flags.See https://msdn.microsoft.com/en-us/library/ms680832(v=vs.85).aspx.
EseDataAccess static library can be used for other ESE inspection applications. EseDataAccess.h contains C++ object-oriented representation of ESE C API. For example, ESE table is represented by EseTable class defined as below.