ISqlQueryBuilder.Select(ISqlBuilder sqlBuilder) Method

.NET Standard 2.x

Adds a column (which is returned by a subquery specified by an ISqlBuilder object) to the select list of a SELECT clause. It uses the name property of the ISqlBuilder object as the alias for this column by default.

Namespace: SnapObjects.Data

Assembly: SnapObjects.Data.dll

Syntax

  ISqlQueryBuilder Select(ISqlBuilder sqlBuilder);

Parameters

sqlBuilder SnapObjects.Data.ISqlBuilder

An ISqlBuilder object which represents a SQL subquery.

Returns

SnapObjects.Data.ISqlQueryBuilder

Returns the current ISqlQueryBuilder object.

Examples

The following code example demonstrates how to use the Select(ISqlBuilder sqlBuilder) method. The column is selected using a subquery.

using SnapObjects.Data;
using System;

namespace Appeon.ApiDoc.ISqlQueryBuilderExamples
{
    public class SelectExample
    {
        private SchoolContext _context;

        public SelectExample(SchoolContext dataContext)
        {
            // Sets Data Context.
            _context = dataContext;
        }

        public void Example1()
        {

            // Declares SqlQueryBuilder.
            var subsqlbuilder = new SqlQueryBuilder();
            var sqlbuilder = new SqlQueryBuilder();

            // Defines a subquery SQL statement and associates the Department table with the Course table 
            // using the WHERE condition: Department.departmentid = course.departmentid.
            subsqlbuilder.Select("name")
                .From("Department")
                .Where("departmentid", "c.departmentid");

            // Defines a SQL statement to retrieve Title values from the "Course" table, 
            // and Name values from the "Department" table.
            sqlbuilder.Select("title")
                .Select(subsqlbuilder)
                .From("course", "c");

            // Converts to raw SQL for the database corresponding to the data context.
            string sql = sqlbuilder.ToSqlString(_context);

            Console.WriteLine(sql);
            
            /*This code produces the following output:
            
            SELECT
            [title],
            (SELECT
            [name]
            FROM [Department]
            WHERE ([departmentid] = [c].[departmentid]))
            FROM [course] AS [c]
            */
        }
    }
}

Applies to

.NET Standard

2.x