2.2.16. ADO Parameter object

发布时间 :2025-10-25 12:23:20 UTC      

Parameter object

ADO Parameter object provides information about a single parameter thatis used in a stored procedure or query.

Parameter object is added to the Parameters gather around. Parameters set with a specific Command object associated with Command object uses this collection to pass parameters inside and outside stored procedures and queries.

Parameters are used to create parameterized commands. These commands (after they have been defined and stored) use parameters to change some of the details of the command before it is executed. For example, SQL SELECT statement can be defined using parameters WHERE clause, while another parameter is used to define SORT BY the name of the column of the clause.

There are four types of parameters: input parameters, output parameters, input/output parameters and return parameters.

Grammar

objectname.property objectname.method

Attribute

Attribute

Description

Attributes

Sets or returns the properties of a Parameter object.

Direction

Sets or returns how a parameter is passed to or back from the stored procedure.

Name

Sets or returns the name of a Parameter object.

NumericScale

Sets or returns the number to the right of the decimal point of the numeric value of a Parameter object.

Precision

Sets or returns the maximum number of numbers allowed when representing a numeric value in a parameter.

Size

Sets or returns the maximum size, in bytes or characters, of the value in the Parameter object.

Type

Sets or returns the type of a Parameter object.

Value

Sets or returns the value of a Parameter object.

Method

Method

Description

AppendChunk

Appends long binary or character data to a Parameter object.

Delete

Removes an object from the Parameters collection.

Principles, Technologies, and Methods of Geographic Information Systems  102

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