DB Tools Database Transaction VI

Owning Palette: Utility VIs

Requires: Database Connectivity Toolkit

Begins, commits, or rolls back a transaction for any type of reference. Wire data to the reference input to determine the polymorphic instance to use or manually select the instance.

Example

Connection

	connection reference specifies a reference to an ADO Connection object.
	operation specifies the operation you want to perform on the transaction. begin Starts a transaction. commit Commits the transaction to the database. rollback Discards the changes made to the database and restores the state of the database to the point when the transaction began.
	isolation level specifies the isolation level used for the transaction. You only need to set isolation level if other transactions might be pending at this same time. chaos Transactions can overwrite each other. read committed This transaction cannot see changes made by other transactions until they are committed. Dirty reads are not possible, but non-repeatable reads and phantom reads are possible. read uncommitted You cannot see uncommitted records from another transaction. Dirty reads, non-repeatable reads, and phantom reads are all possible. repeatable read You cannot see any changes in records without requerying the database. Dirty reads and non-repeatable reads are not possible, but phantom reads are possible. serializable The transaction occurs in complete isolation. Dirty reads, non-repeatable reads, and phantom reads are not possible.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	connection reference out returns a reference to an ADO Connection object.
	error out contains error information. This output provides standard error out functionality.

Command (C)

	command reference specifies a reference to an ADO Command object.
	operation specifies the operation you want to perform on the transaction. begin Starts a transaction. commit Commits the transaction to the database. rollback Discards the changes made to the database and restores the state of the database to the point when the transaction began.
	isolation level specifies the isolation level used for the transaction. You only need to set isolation level if other transactions might be pending at this same time. chaos Transactions can overwrite each other. read committed This transaction cannot see changes made by other transactions until they are committed. Dirty reads are not possible, but non-repeatable reads and phantom reads are possible. read uncommitted You cannot see uncommitted records from another transaction. Dirty reads, non-repeatable reads, and phantom reads are all possible. repeatable read You cannot see any changes in records without requerying the database. Dirty reads and non-repeatable reads are not possible, but phantom reads are possible. serializable The transaction occurs in complete isolation. Dirty reads, non-repeatable reads, and phantom reads are not possible.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	command reference out returns a reference to an ADO Command object.
	error out contains error information. This output provides standard error out functionality.

Command (CR)

	command-recordset reference specifies a reference that combines an ADO Command object and an ADO Recordset object.
	operation specifies the operation you want to perform on the transaction. begin Starts a transaction. commit Commits the transaction to the database. rollback Discards the changes made to the database and restores the state of the database to the point when the transaction began.
	isolation level specifies the isolation level used for the transaction. You only need to set isolation level if other transactions might be pending at this same time. chaos Transactions can overwrite each other. read committed This transaction cannot see changes made by other transactions until they are committed. Dirty reads are not possible, but non-repeatable reads and phantom reads are possible. read uncommitted You cannot see uncommitted records from another transaction. Dirty reads, non-repeatable reads, and phantom reads are all possible. repeatable read You cannot see any changes in records without requerying the database. Dirty reads and non-repeatable reads are not possible, but phantom reads are possible. serializable The transaction occurs in complete isolation. Dirty reads, non-repeatable reads, and phantom reads are not possible.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	command-recordset reference out returns a reference that combines an ADO Command object and an ADO Recordset object.
	error out contains error information. This output provides standard error out functionality.

Example

Refer to the Database Transaction VI in the labview\examples\database directory for an example of using the DB Tools Database Transaction VI.