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    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

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