On-line access to data from depository databases
Depository databases on Sybase platform
The basic requirement for accessing the data from the depositories is the usage of Adaptive Server Anywhere in the version 7.x and higher. Network Server must be used in the application, because unlike Standalone Engine, is not limited in the number of databases opened in parallel.
For accessing the data, it is necessary to mount the depositories into the archive, which created them, using the TELL command MOUNT_TREZOR (unless the depository was automatically mounted if TrezorCompressOffline=0). The TELL command may be entered either from the process D2000 Application Manager or from the process D2000 Tell. The command contains only the parameter path\depository_name. The parameters define the path and name of the depository database that will be mounted. In this name, the characters '*' and '?' may be used for the mask definition. If more files match the entered mask, all these ones will be mounted. The first mounting of the new depository executes the analysis of data in the depository. Repeated mounting of the depository is very quickly. After mounting, the data are available to all users in such a way as the data from the on-line archive database. So, from D2000 HI environment - select the time interval when opening the graph, or when reading historical values into the table.
The parameter AutoMountPath may be given in the archive configuration. The parameter contains the path to the file. All the depositories from the given directory are to be mounted during the start of the process D2000 Archiv.
The TELL command DISMOUNT_TREZOR is used to dismount the used depository database. It may contain, as well as the command for mounting, the only parameter with the same properties and there is a possibility to dismount all depository databases - the parameter all. Data from the depositories, which was dismounted, are not available.
Note: The reading from depository databases Trezor.db and TrezorP.db,
which are placed
in subdirectories Trezor
and Trezor\Prev
of application
directory, is supported from the version D2000 7.02.008 Release 83 and later.
These depositories will be mounted when they are created or opened
and dismounted before they will be disconnected, transferred
and compressed. These depositories can be dismount by TELL command DISMOUNT_TREZOR
and then mount by TELL command MOUNT_TREZOR.
The mounting/dismounting relate only to reading from actual filled depositories
- the mounting and dismounting do not influence the writing into depositories.
The reading of actual filled depositories allows to configure the archive
object that have very low depth of archiving (e.g. 1 day - because of saving the
space in archive database). The archive values of these archive objects will be
always available at least with the time depth that is equal to the period of the
creating the depository databases (e.g. 2 weeks).
Depository databases on Oracle platform
For making depository database data available, you must mount the required
depository to the archive, that created them, using the TELL command
MOUNT_TREZOR (unless the depository was automatically mounted if TrezorCompressOffline=0).
The TELL command may be entered either from the process
D2000 Application Manager or from the process
D2000 Tell. The command takes one or two parameters.
You may enter either the depository database number (e.g.
14) or the depository database name (e.g. TEST_TS_TREZOR14). If
you enter two parameters, they must specify the numbers of depository databases
- begin and end of a sequence of depository databases. The sequence may include
depository databases that have been already mounted. User is responsible for the
right location of the depository databases' datafiles (if
they have been moved, user must either copy them to their original
locations or change their locations in the Oracle database using the command:
ALTER TABLESPACE RENAME
DATAFILE 'old_location' TO 'new_location').
After mounting, the data are available to all users in such a way as the data from
the on-line archive database. So, from D2000 HI environment
- select the time
interval when opening the graph, or
when reading historical values
into the table.
Note: When using of depository database segments, the Tell command MOUNT_TREZOR can contain two more parameters: SEGMENT seg, where seg is the number of the depository database segment. If the parameters SEGMENT seg are not specified, the process D2000 Archiv attempts to mount on all segments.
The TELL command DISMOUNT_TREZOR is used to dismount the used depository database. It may contain, as well as the command for mounting, one or two parameters with the same properties and there is also the possibility to dismount all depository databases - the parameter all. Data from the depositories that was dismounted are not available.
Note: When using depository database segments, the Tell command DISMOUNT_TREZOR can contain two more parameters: SEGMENT seg, where seg is the number of the depository database segment. If the parameters SEGMENT seg are not used, the process D2000 Archiv attempts to dismount all segments.
Depository databases on PostgreSQL platform
For making depository database data available, you must mount the required
depository to the archive, that created them, using the TELL command
MOUNT_TREZOR (unless the depository was automatically mounted if TrezorCompressOffline=0).
The TELL command may be entered either from the process
D2000 Application Manager or from the process
D2000 Tell. The command takes one or two parameters.
You may enter the depository database number (e.g. 14). If
you enter two parameters, they must specify the numbers of depository databases
- begin and end of a sequence of depository databases. The sequence may include
depository databases that have been already mounted. User is responsible for the
right location of the files and directories of depository databases (if they had been moved away previously), so that PostgreSQL
database server can open and access them.
After mounting, the data are available to all users in such a way as the data from
the on-line archive database. So, from D2000 HI environment
- select the time interval when opening the graph, or when reading historical values into the table.
Note: When using depository database segments, the Tell command MOUNT_TREZOR can contain two more parameters: SEGMENT seg, where seg is the number of the depository database segment. If the parameters SEGMENT seg are not specified, the process D2000 Archiv attempts to mount on all segments.
The TELL command DISMOUNT_TREZOR is used to dismount the used depository database. It may contain, as well as the command for mounting, one or two parameters with the same properties and there is also the possibility to dismount all depository databases - the parameter all. Data from the depositories that was dismounted are not available.
Note: When using depository database segments, the Tell command DISMOUNT_TREZOR can contain two more parameters: SEGMENT seg, where seg is the number of the depository database segment. If the parameters SEGMENT seg are not used, the process D2000 Archiv attempts to dismount all segments.
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