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    IQueryAndOrBuilder<TModel>.AndWhereIsNotNull(string left) Method

    .NET Standard 2.x

    Adds the AND logical operator and a search condition to the WHERE clause; and uses IS NOT NULL operator to search for values that are not null.

    Namespace: SnapObjects.Data

    Assembly: SnapObjects.Data.dll

    Syntax

      IQueryAndOrBuilder<TModel> AndWhereIsNotNull(string left);
    

    Parameters

    left System.String

    A SQL expression on the left of the IS NOT NULL operator.

    Returns

    IQueryAndOrBuilder<TModel>

    Returns anIQueryAndOrBuilder<TModel> object which can be used to add more search conditions to the current WHERE clause.

    Examples

    The following code example demonstrates how to use the AndWhereIsNotNull method to add an AND IS NOT NULL condition to the WHERE clause. In this example, the IS NOT NULL condition specifies that the HireDate value cannot be null.

    using Appeon.ApiDoc.Models.School;
    using SnapObjects.Data;
    using System;
    using System.Threading.Tasks;
    
    namespace Appeon.ApiDoc.IQueryAndOrBuilderExamples
    {
        public class AndWhereIsNotNullExample
        {
            private SchoolContext _context;
            
            public AndWhereIsNotNullExample(SchoolContext dataContext)
            {
                // Sets Data Context
                _context = dataContext;
            }
    
            public async Task<int> Example() 
            {
                // Get a QueryBuilder.
                var Builder = _context.SqlModelMapper.GetQueryBuilder<Person>();
                
                // Defines a WHERE condition that the column of EnrollmentDate is not empty.
                Builder.WhereIsNotNull("EnrollmentDate")
                       .AndWhereIsNotNull("HireDate");
                
                var result = (await Builder.LoadAsync()).FirstOrDefault();
                
                if (result != null) 
                {
                    Console.WriteLine("PersonID:    {0}", result.PersonID);
                    Console.WriteLine("FirstName:   {0}", result.FirstName);
                    Console.WriteLine("LastName:    {0}", result.LastName);
                    Console.WriteLine("HireDate:    {0}", result.HireDate);
                    Console.WriteLine("EnrollmentDate:  {0}", result.EnrollmentDate);
                    Console.WriteLine("Discriminator:   {0}", result.Discriminator);
                    
                    return result.PersonID;
                }
                else 
                {
                    Console.WriteLine("Not found!");
                    
                    return 0;
                }
                
                /*This code example produces the following output:   
                
                    PersonID:    3015
                    FirstName:   Chen
                    LastName:    Ward
                    HireDate:    10/12/1997 12:00:00 AM
                    EnrollmentDate:  1/1/2019 12:00:00 AM
                    Discriminator:   Student
                */
            }
        }
    }
    

    Example Refer To

    Model Class: Person

    Applies to

    .NET Standard

    2.x

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