ISqlHavingBuilder.Having(string left, ISqlParameter parameter) Method
.NET Standard 2.x
Creates a HAVING
clause, and adds a search condition to the HAVING
clause. You can specify a SQL expression on the left of the operator and a SQL parameter on the right of the operator. The operator is '='.
Namespace: SnapObjects.Data
Assembly: SnapObjects.Data.dll
Syntax
ISqlHavingAndOr Having(string left, ISqlParameter parameter);
Parameters
condition
System.String
A SQL expression on the left of the operator.
parameter
SnapObjects.Data.ISqlParameter
An ISqlParameter
object which represents a SQL parameter on the right of the operator.
It can be created by calling the SqlBuilder.Parameter method.
Returns
SnapObjects.Data.ISqlHavingAndOr
Returns the ISqlHavingAndOr
object which can be used to add more search conditions to the current HAVING
clause.
Examples
The following code example demonstrates how to use the Having method to specify the HAVING condition for groups.
using SnapObjects.Data;
using System;
namespace Appeon.ApiDoc.ISqlHavingBuilderExamples
{
public class HavingExample
{
private readonly SchoolContext _context;
public HavingExample(SchoolContext dataContext)
{
// Sets the data context.
_context = dataContext;
}
public void Example1()
{
var sqlQueryBuilder = new SqlQueryBuilder();
// Groups "StudentGrade" table by StudentID and CourseID, and gets the sum of Grade of each group.
// Specifies the HAVING condition for group to: StudentID equal to the input parameter.
// The value of input parameter is specified when SQL is executed.
sqlQueryBuilder
.Select("StudentID")
.Select("sum(Grade)")
.From("StudentGrade")
.GroupBy("StudentID, CourseID")
.Having("StudentID", SqlBuilder.Parameter<int>("studentid"));
// Converts to raw SQL for the database corresponding to the data context.
string sql = sqlQueryBuilder.ToSqlString(_context);
Console.WriteLine(sql);
// Executes the SQL and specifies "6" for the input parameter.
var studentGrade = _context.SqlExecutor.Select<DynamicModel>(sql, 6);
/*This code example produces the following output:
SELECT
[StudentID],
sum(Grade)
FROM [StudentGrade]
GROUP BY
[StudentID],
[CourseID]
HAVING ([StudentID] = @studentid)
*/
}
}
}
Applies to
.NET Standard
2.x