HP 3000 Manuals HP 3000 Manuals
What Is DBChange Plus?
DBChange Plus is a command-driven utility that allows you to perform many
necessary TurboIMAGE/XL database management system tasks. DBChange Plus
does a variety of changes and maintenance functions while preserving user
data. DBChange Plus does not have to unload and reload the data.
Table 1-1 describes some functions of DBChange Plus.
Table 1-1. DBChange Plus Functions
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| | |
| Function | Description |
| | |
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| | |
| Restructuring | Adding, deleting, reordering, renaming, and general |
| | management of data items, data sets, fields, sort items, and |
| | paths. Redefining primary paths. |
| | |
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| | |
| Copying | Copying a database within a group, across groups, and across |
| | accounts. |
| | |
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| | |
| Displaying structural | Reviewing information about data items, data sets, fields, |
| information | sort items, and paths. Printing the schema. |
| | |
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| | |
| Security management | Adding, deleting, and changing passwords and user class |
| | access. |
| | |
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| | |
| Maintenance and | Capacity management. Detail data set repacking to clean up |
| performance tuning | messy chains. Checking and fixing structural problems. |
| | Selective placement of data sets on specific disk classes. |
| | Smart reblocking. |
| | |
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| | |
| Erasing | Bulk erasing of data set entries. |
| | |
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DBChange Plus contains two programs: DBCPLUS and DBAPLUS.
The DBCPLUS program accepts and stores your requests in a change file.
The change file contains information about the database and also contains
requests for changes as specified by the DBChange Plus commands.
The DBAPLUS program performs the actual restructuring or maintenance of
the database. DBAPLUS can be invoked either from within the
DBCPLUS program by issuing a PERFORM COMMANDS, or it can be invoked
independently.
DBChange Plus Operation
You can use DBChange Plus either interactively or in batch mode. When
using DBChange Plus interactively, you are prompted for commands and
other input, and you receive error and information messages on your
terminal screen. DBChange Plus is usually used interactively for
non-repetitive tasks that require immediate attention. To use DBChange
Plus in batch mode, you send input to DBChange Plus from a text file
called a job file that contains DBChange Plus and MPE XL commands. Batch
mode is usually used for repetitive or time-consuming tasks.
You can also execute DBChange Plus commands from a text file called a
command file. Command files can either be used interactively or in batch
mode. Job files and command files are discussed later in this chapter
under, "Executing DBChange Plus Commands from a File."