Session.ExecuteScalar(String, QueryParameterCollection) Method

Executes the specified SQL query and returns the first column of the first row in the result set returned by the query.

Namespace: DevExpress.Xpo

Assembly: DevExpress.Xpo.v24.2.dll

Declaration

C#

public object ExecuteScalar(
    string sql,
    QueryParameterCollection parameters
)

VB.NET

Public Function ExecuteScalar(
    sql As String,
    parameters As QueryParameterCollection
) As Object

Parameters

Name	Type	Description
sql	String	Specifies an SQL statement.
parameters	QueryParameterCollection	Specifies query parameter values.

Returns

Type	Description
Object	The first column of the first row in the query’s result set. A null reference (Nothing in Visual Basic) if the result set does not contain columns. DBNull.Value if the first column does not contain a value.

Remarks

Use the ExecuteScalar method to query data stores for a single or aggregate value, without having to retrieve a result set.

Use QueryParameterCollection to pass strongly-typed parameters. See examples here: Always Encrypted (SQL Server only).

The connection provider automatically generates sequential parameter names (p0, p1, p2 …). To specify custom parameter names, use the overloaded ExecuteScalar(String, String[], QueryParameterCollection) method.

To learn more about executing SQL statements in XPO, refer to Direct SQL Queries.

Note

The ExecuteScalar method sends statements directly, so the correct statement syntax and parameter names format depends on a particular database server.