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Owning Palette: Database Writing VIs

Installed With: DSC Module

Opens a trace in a Citadel database to allow writing. Use the Close Trace VI to close the reference opened by this VI.

You must manually select the polymorphic instance to use. If you do not wire the database URL parameter, the VI writes data to the database associated with the default LabVIEW Datalogging and Supervisory Control (DSC) Module process. This VI returns an error if there is already an active writer for the selected trace.

Use the pull-down menu to select an instance of this VI.

Select an instance Open Trace (Numeric)Open Trace (Logical)Open Trace (String)Open Trace (Bit Array)Open Trace (Variant)

Open Trace (Numeric)

	value precision is the precision with which Citadel stores numeric values. Citadel truncates values to the given precision when compressing data points for storage. Truncating values might help reduce the size of the database on disk. Use a precision value of 0 to store uncompressed values. The default precision is 0.01.
	timeout limits the time that the writer waits when contacting the Citadel database. The default is 30 seconds. A timeout value of less than or equal to 0 indicates no timeout, and the writer waits indefinitely until the data is returned.
	database URL is the computer name and the database name where the Citadel database resides. Enter the database URL in the format \\computer\database_name. For example, if you have a copy of the LabVIEW Datalogging and Supervisory Control (DSC) Module and Citadel service installed on a computer named datalogger and the name of the database on that computer is data, you can access the data on datalogger from another computer by using the path \\datalogger\data. If you provide a database name only, the DSC Module searches for the database on the local computer. If you do not wire database URL, the VI reads data from the database associated with the default DSC Module process.
	process name is the name of the group to which this trace belongs. This parameter must be a string of numbers and letters without spaces.
	trace name is the name of the Citadel trace. If a trace with this name does not exist in the target database, the DSC Module creates a new trace. Otherwise, Citadel appends data to the end of the existing trace.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	trace attributes contains information about trace attributes. time precision is the precision with which Citadel stores timestamps. Citadel truncates timestamps to the given precision when compressing data points for storage, which might reduce the size of the database on disk. Use a precision value of 0 to store an uncompressed timestamp with each data point. The default time precision is 1 millisecond.
	step value determines the default line style used to display data points in the NI HyperTrend control. If this parameter is FALSE (default), the NI HyperTrend control draws smooth lines between points. If this parameter is TRUE, the NI HyperTrend control draws discrete steps between points.
	trace reference is the refnum associated with the open writer. If this VI fails, trace reference returns Not A Refnum.
	database URL out returns the computer name and the database name to specify where the Citadel database resides. The format is \\computer\database_name.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

Open Trace (Logical)

	timeout limits the time that the writer waits when contacting the Citadel database. The default is 30 seconds. A timeout value of less than or equal to 0 indicates no timeout, and the writer waits indefinitely until the data is returned.
	database URL is the computer name and the database name where the Citadel database resides. Enter the database URL in the format \\computer\database_name. For example, if you have a copy of the LabVIEW Datalogging and Supervisory Control (DSC) Module and Citadel service installed on a computer named datalogger and the name of the database on that computer is data, you can access the data on datalogger from another computer by using the path \\datalogger\data. If you provide a database name only, the DSC Module searches for the database on the local computer. If you do not wire database URL, the VI reads data from the database associated with the default DSC Module process.
	process name is the name of the group to which this trace belongs. This parameter must be a string of numbers and letters without spaces.
	trace name is the name of the Citadel trace. If a trace with this name does not exist in the target database, the DSC Module creates a new trace. Otherwise, Citadel appends data to the end of the existing trace.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	trace attributes contains information about trace attributes. time precision is the precision with which Citadel stores timestamps. Citadel truncates timestamps to the given precision when compressing data points for storage, which might reduce the size of the database on disk. Use a precision value of 0 to store an uncompressed timestamp with each data point. The default time precision is 1 millisecond.
	trace reference is the refnum associated with the open writer. If this VI fails, trace reference returns Not A Refnum.
	database URL out returns the computer name and the database name to specify where the Citadel database resides. The format is \\computer\database_name.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

Open Trace (String)

	timeout limits the time that the writer waits when contacting the Citadel database. The default is 30 seconds. A timeout value of less than or equal to 0 indicates no timeout, and the writer waits indefinitely until the data is returned.
	database URL is the computer name and the database name where the Citadel database resides. Enter the database URL in the format \\computer\database_name. For example, if you have a copy of the LabVIEW Datalogging and Supervisory Control (DSC) Module and Citadel service installed on a computer named datalogger and the name of the database on that computer is data, you can access the data on datalogger from another computer by using the path \\datalogger\data. If you provide a database name only, the DSC Module searches for the database on the local computer. If you do not wire database URL, the VI reads data from the database associated with the default DSC Module process.
	process name is the name of the group to which this trace belongs. This parameter must be a string of numbers and letters without spaces.
	trace name is the name of the Citadel trace. If a trace with this name does not exist in the target database, the DSC Module creates a new trace. Otherwise, Citadel appends data to the end of the existing trace.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	trace attributes contains information about trace attributes. time precision is the precision with which Citadel stores timestamps. Citadel truncates timestamps to the given precision when compressing data points for storage, which might reduce the size of the database on disk. Use a precision value of 0 to store an uncompressed timestamp with each data point. The default time precision is 1 millisecond.
	trace reference is the refnum associated with the open writer. If this VI fails, trace reference returns Not A Refnum.
	database URL out returns the computer name and the database name to specify where the Citadel database resides. The format is \\computer\database_name.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

Open Trace (Bit Array)

	timeout limits the time that the writer waits when contacting the Citadel database. The default is 30 seconds. A timeout value of less than or equal to 0 indicates no timeout, and the writer waits indefinitely until the data is returned.
	database URL is the computer name and the database name where the Citadel database resides. Enter the database URL in the format \\computer\database_name. For example, if you have a copy of the LabVIEW Datalogging and Supervisory Control (DSC) Module and Citadel service installed on a computer named datalogger and the name of the database on that computer is data, you can access the data on datalogger from another computer by using the path \\datalogger\data. If you provide a database name only, the DSC Module searches for the database on the local computer. If you do not wire database URL, the VI reads data from the database associated with the default DSC Module process.
	process name is the name of the group to which this trace belongs. This parameter must be a string of numbers and letters without spaces.
	trace name is the name of the Citadel trace. If a trace with this name does not exist in the target database, the DSC Module creates a new trace. Otherwise, Citadel appends data to the end of the existing trace.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	trace attributes contains information about trace attributes. time precision is the precision with which Citadel stores timestamps. Citadel truncates timestamps to the given precision when compressing data points for storage, which might reduce the size of the database on disk. Use a precision value of 0 to store an uncompressed timestamp with each data point. The default time precision is 1 millisecond.
	trace reference is the refnum associated with the open writer. If this VI fails, trace reference returns Not A Refnum.
	database URL out returns the computer name and the database name to specify where the Citadel database resides. The format is \\computer\database_name.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

Open Trace (Variant)

	timeout limits the time that the writer waits when contacting the Citadel database. The default is 30 seconds. A timeout value of less than or equal to 0 indicates no timeout, and the writer waits indefinitely until the data is returned.
	database URL is the computer name and the database name where the Citadel database resides. Enter the database URL in the format \\computer\database_name. For example, if you have a copy of the LabVIEW Datalogging and Supervisory Control (DSC) Module and Citadel service installed on a computer named datalogger and the name of the database on that computer is data, you can access the data on datalogger from another computer by using the path \\datalogger\data. If you provide a database name only, the DSC Module searches for the database on the local computer. If you do not wire database URL, the VI reads data from the database associated with the default DSC Module process.
	process name is the name of the group to which this trace belongs. This parameter must be a string of numbers and letters without spaces.
	trace name is the name of the Citadel trace. If a trace with this name does not exist in the target database, the DSC Module creates a new trace. Otherwise, Citadel appends data to the end of the existing trace.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	trace attributes contains information about trace attributes. time precision is the precision with which Citadel stores timestamps. Citadel truncates timestamps to the given precision when compressing data points for storage, which might reduce the size of the database on disk. Use a precision value of 0 to store an uncompressed timestamp with each data point. The default time precision is 1 millisecond.
	trace reference is the refnum associated with the open writer. If this VI fails, trace reference returns Not A Refnum.
	database URL out returns the computer name and the database name to specify where the Citadel database resides. The format is \\computer\database_name.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.