public void ShouldCreateConcatExpression()
{
var factory = new DbExpressionFactory();
var expression = factory.Concat(factory.Constant("DummyExpression"),
factory.Constant("AnotherDummyExpression"));
Assert.IsNotNull(expression.LeftExpression);
Assert.IsNotNull(expression.RightExpression);
Assert.IsTrue(expression.ExpressionType == DbExpressionType.Concat);
}
/// <summary>
/// Specifies the tables, views, derived tables, and joined tables used in DELETE, SELECT, and UPDATE statements.
/// </summary>
/// <param name="query">The target <see cref="DbQuery{TQueryExpression}"/></param>
/// <param name="expression">A <see cref="DbExpression"/> that represents the from clause.</param>
/// <returns><see cref="DbQuery{TQueryExpression}"/></returns>
public static DbQuery <TQueryExpression> From <TQueryExpression>(this DbQuery <TQueryExpression> query, DbExpression expression)
where TQueryExpression : DbQueryExpression, new()
{
var dbExpression = expression;
if (!query.QueryExpression.FromExpression.IsNull())
{
if (dbExpression.ExpressionType == DbExpressionType.Join)
{
dbExpression = DbExpressionFactory.Concat(query.QueryExpression.FromExpression, dbExpression);
}
else
{
dbExpression = DbExpressionFactory.List(new[] { query.QueryExpression.FromExpression, expression });
}
}
query.QueryExpression.FromExpression = dbExpression;
return(query);
}
public void ShouldCreateConcatExpression()
{
var factory = new DbExpressionFactory();
var expression = factory.Concat(factory.Constant("DummyExpression"),
factory.Constant("AnotherDummyExpression"));
Assert.IsNotNull(expression.LeftExpression);
Assert.IsNotNull(expression.RightExpression);
Assert.IsTrue(expression.ExpressionType == DbExpressionType.Concat);
}
