To define Vision parameters and trace file options, press the "Vision options. . ." button when defining data source names in the AcuODBC Setup dialog box. A dialog box displays.
In this box, you can set the Vision file parameters: Max. Files, Max. Locks, Locks Per File, and Buffers. You can also request Vision and AcuODBC trace files for debugging purposes, define parameters for use with the AcuServer remote file server, and/or activate transaction management logging. Complete the fields as instructed below.
Vision Parameters
Max. Files
This parameter equates to the MAX-FILES variable in the runtime configuration file. It sets the maximum number of files that can be opened by AcuODBC. The default is "32". Keeping this value small conserves memory.
Max. Locks
This parameter equates to the MAX-LOCKS variable in the runtime configuration file. It sets the maximum number of record locks that can be held by AcuODBC for all of the files together. The default matches the setting of "Max. Files," in this case "32". The maximum value is "8191" for Vision files. Setting this variable to its maximum value can waste resources and is not recommended.
Locks Per File
This parameter equates to the LOCKS-PER-FILE variable in the runtime configuration file. It sets the maximum number of record locks that can be held on a file when an SQL transaction has been issued by the Windows application. This value affects only the files that are maintaining multiple record locks. Typically, all read records for updating or deleting transaction data are locked. The field lets you increase the number of locks per file so you can manage large transactions. The default setting is "10". The maximum value is "8191" for Vision files. Setting this variable to its maximum value can waste resources and is not recommended.
Buffers
This variable equates to the V-BUFFERS variable in the runtime configuration file. It lets you set the number of indexed block buffers to allocate. These buffers are used to improve the performance of indexed files. Each buffer is 512 bytes plus some overhead. Setting this number larger will generally improve file performance. Setting it smaller will save memory. The value can range from "0" (no buffering) to "256". The default is "32".
AcuServer Parameters
Default Timeout
Use this field to specify a timeout for use when connecting to a remote Vision file via AcuServer. Enter the length of time in seconds that AcuODBC should wait for a response from AcuServer before timing out.
Server Port
Enter the port number assigned to the AcuServer host if it is different from the default port number, "6523". This field is useful for redirecting additional instances of AcuServer or for working around a firewall.
Debug Options
Vision Trace
This field lets you turn Vision file tracing on and off. Possible values are from "0" to "9"; the higher the number, the more detailed the trace file. A value of "0" or "-1" turns file tracing off. The Vision trace file lists all the Vision file operations attempted by AcuODBC. By default, the trace file is placed in the root directory of the AcuODBC client under the name, "visionn.log" where n is a number that increments each time a log file is created.
AcuODBC Trace
This field lets you turn AcuODBC tracing on and off. Possible values are from "0" to "2"; the higher the number, the more detailed the trace file. A value of "0" or "-1" turns AcuODBC tracing off. The trace file lists all the SQL command operations attempted by AcuODBC. By default, the trace file is placed in the root directory of the AcuODBC client under the name, "acuodbcn.log" where n is a number that increments each time a log file is created.
| 0
| no trace
|
| 1
| SQL trace
|
| 2
| SQL trace plus a message box with some error (e.g., "File not found!") |
Select this checkbox to enable or disable transaction support in AcuODBC. If you are in a transaction processing environment, enable this feature to begin transaction management, logging, locking, and other key functions. Disable this feature to turn off the transaction system in order to complete very complex SQL operations on expansive transactions.
Transaction Parameters
LogFile
This identifies the name of the log file to be used for transaction management logging. (Activate transaction management logging by selecting the "Logging" checkbox.) When logging is on, the log file is opened at the beginning of the first transaction encountered with AcuODBC. If the file does not exist, one is created.
You may store your transaction log file on a remote machine if your system utilizes AcuServer. To specify a remote filename for LogFile, use remote name notation in this field.
Remote name notation has the following format:
@server-name:path-name/file-name
Log files prepended with "@server-name:path-name" are routed to AcuServer on the host specified by server-name, and stored in the directory specified by path-name.
LogDir
This variable allows you to specify a directory to be used for holding the temporary files generated by the transaction management system. The value of LogDir is treated as a prefix. If no directory is specified, temporary files are placed in the current directory.
LogBufferSize
This sets the maximum buffer size, in bytes, for the transaction log file. Acceptable values are from "0" to "32767". LogBufferSize is examined before each write to the log file. Its default value is "512". If LogBufferSize is set to "0", then writes to the log file are synchronous (unbuffered).
Logging
Select/deselect this checkbox to enable/disable transaction management logging. When this box is checked, file updates are logged to the transaction log file specified in the "LogFile" field. By default, logging is off.
LogEncryption
If this box is checked, record images are encrypted before they are written to the transaction log file. By default, log encryption is off.
LogDevice
Selecting this box causes the transaction management system to assume that the log file is actually a device, rather than a file. This means that a special device locking method will be used on the log file. It also guarantees that the log file will be opened "append" and that no seeks will be performed on it. This allows for the use of a tape device for the log file on many systems. By default, this option is turned off.