Sum

This method is used to compute the sum value of the target field.

Code Snippets

Below is the sample code that gets the sum value of column Value from the [dbo].[Sales] table for a specific customer since yesterday.

using (var connection = new SqlConnection(connectionString))
{
    var customerExpenses = connection.Sum<Sales>(e => e.Value,
        e => e.CustomerId == 10045 && e.DateInsertedUtc >= DateTime.UtcNow.Date.AddDays(-1));
}

Targeting a Table

You can also target a specific table by passing the literal table and field name like below.

using (var connection = new SqlConnection(connectionString))
{
    var customerExpenses = connection.Sum("[dbo].[Sales]",
        Field.From("Value"), new { State = "Michigan" });
}

Or, use the QueryGroup or QueryField if you are to enhance the WHERE expressions.

using (var connection = new SqlConnection(connectionString))
{
    var where = new []
    {
        new QueryField("CustomerId", 10045),
        new QueryField("DateInsertedUtc", Operation.GreaterThanOrEqual, DateTime.UtcNow.Date.AddDays(-1))
    }
    var customerExpenses = connection.Sum("[dbo].[Sales]", Field.From("Value"), where: where);
}

Table Hints

To pass a hint, simply write the table-hints and pass it in the hints argument.

using (var connection = new SqlConnection(connectionString))
{
    var customerExpenses = connection.Sum<Sales>(e => e.Value,
        e => e.CustomerId == 10045 && e.DateInsertedUtc >= DateTime.UtcNow.Date.AddDays(-1),
        hints: "WITH (NOLOCK)");
}

Or, you can use the SqlServerTableHints class.

using (var connection = new SqlConnection(connectionString))
{
    var customerExpenses = connection.Sum<Sales>(
        e => e.CustomerId == 10045 && e.DateInsertedUtc >= DateTime.UtcNow.Date.AddDays(-1),
        hints: SqlServerTableHints.NoLock);
}