AVEVA™ Production Management

OLE-DB variable properties

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OLE-DB variable properties

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Last UpdatedSep 06, 2023
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Refer to the following tables for the key configurable properties of OLE-DB variable.

Data properties

Property	Description	Valid values
LastSample	The last sample written to the historical stream of samples.
SampleTypeCode	The data type of the sample stream for the variable. The data type must be compatible with the data type of the returning SQL query.	Boolean, DateTime, Double, Event, Int32, Int64, Single, String.
Value	The value of the last sample written to the historical stream of samples. You can also use this property to directly change the value.

Property

Description

Valid values

LastSample

The last sample written to the historical stream of samples.

SampleTypeCode

The data type of the sample stream for the variable.

The data type must be compatible with the data type of the returning SQL query.

Boolean, DateTime, Double, Event, Int32, Int64, Single, String.

Value

The value of the last sample written to the historical stream of samples. You can also use this property to directly change the value.

SampleTypeCode options

Data Type	Description
Boolean	The Boolean data type is an unsigned value that is interpreted as either True or False.
DateTime	12:00:00 midnight, January 1, 0001 A.D. to 11:59:59 P.M., December 31, 9999 A.D.
Double	Double variables have an approximate range of ±5.0 × 10^-324 to ±1.7 × 10^308 to a precision of 15-16 significant digits.
Event	An event data stream records the time that important events occurred.
Int32	Integer variables are stored as signed 32-bit (4-byte) ranging from -2,147,483, 647 through 2,147,483,647.
Int64	Long variables are stored as signed 64-bit (8-byte) integers ranging in value from -9,223,372,036,854,775,808 through 9,223,372,036,854,775,807.
Single	Single variables have an approximate range of ±1.5 × 10^-45 to ±3.4 × 10^38 to a precision of 7 digits.
String	String values are used for storing text as Unicode characters.

Miscellaneous properties

Property	Description	Valid values
Address	Defines the SQL Select statement that AVEVA™ Production Management uses to query the database to obtain the value for the variable. This is the format of the Select statement: SELECT <SelectValue> FROM <TableName> WHERE <WhereCondition> Example For the Select statement SELECT orderid FROM orders WHERE orderid=10300, the variable results in a value of 10300. AVEVA Production Management updates the value of the running OleDbVariable item every time the OleDbDataSource item polls the OLE DB provider according to the PollInterval property setting of the OleDbDataSource item and the database connection settings of the OleDbConnection item.	A valid SQL Select statement
Samples	The stream of historical samples. Each sample contains a value, a quality, and a time stamp.	Sample stream

Property

Description

Valid values

Address

Defines the SQL Select statement that AVEVA™ Production Management uses to query the database to obtain the value for the variable.

This is the format of the Select statement:

SELECT <SelectValue> FROM <TableName> WHERE <WhereCondition>

Example

For the Select statement SELECT orderid FROM orders WHERE orderid=10300, the variable results in a value of 10300.

AVEVA Production Management updates the value of the running OleDbVariable item every time the OleDbDataSource item polls the OLE DB provider according to the PollInterval property setting of the OleDbDataSource item and the database connection settings of the OleDbConnection item.

A valid SQL Select statement

Samples

The stream of historical samples. Each sample contains a value, a quality, and a time stamp.

Sample stream

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