public void ShouldCreateEmptyListExpression()
{
var factory = new DbExpressionFactory();
var expression =
factory.List();
Assert.IsTrue(expression.Count() == 0);
Assert.IsTrue(expression.ExpressionType == DbExpressionType.List);
}
public void ShouldCreateListExpression()
{
var factory = new DbExpressionFactory();
var expression =
factory.List(new DbExpression[] { factory.Column("SomeColumn"), factory.Column("SomeOtherColumn") });
Assert.IsTrue(expression.Count() == 2);
Assert.IsTrue(expression.ExpressionType == DbExpressionType.List);
}
/// <summary>
/// Specifies the column to be updated.
/// </summary>
/// <param name="dbUpdateQuery">The target <see cref="DbQuery{TQueryExpression}"/>.</param>
/// <param name="target">The <see cref="DbExpression"/> that represents the target table or view.</param>
/// <param name="valueExpression">The <see cref="DbExpression"/> that represents the new value.</param>
/// <returns><see cref="DbQuery{TQueryExpression}"/></returns>
public static DbQuery <DbUpdateExpression> Set(this DbQuery <DbUpdateExpression> dbUpdateQuery, DbExpression target, DbExpression valueExpression)
{
var dbExpression = (DbExpression)DbExpressionFactory.Assign(target, valueExpression);
if (!dbUpdateQuery.QueryExpression.SetExpression.IsNull())
{
dbExpression = DbExpressionFactory.List(new[] { dbUpdateQuery.QueryExpression.SetExpression, dbExpression });
}
dbUpdateQuery.QueryExpression.SetExpression = dbExpression;
return(dbUpdateQuery);
}
/// <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 ShouldCreateListExpression()
{
var factory = new DbExpressionFactory();
var expression =
factory.List(new DbExpression[] { factory.Column("SomeColumn"), factory.Column("SomeOtherColumn") });
Assert.IsTrue(expression.Count() == 2);
Assert.IsTrue(expression.ExpressionType == DbExpressionType.List);
}
public void ShouldCreateEmptyListExpression()
{
var factory = new DbExpressionFactory();
var expression =
factory.List();
Assert.IsTrue(expression.Count() == 0);
Assert.IsTrue(expression.ExpressionType == DbExpressionType.List);
}
/// <summary>
/// Specifies the projecton of the query.
/// </summary>
/// <param name="dbSelectQuery">The target <see cref="DbSelectQuery"/></param>
/// <param name="expressionSelector">A <see cref="Func{T,TResult}"/> used to specify the <see cref="DbExpression"/> that represents the projection.</param>
/// <returns></returns>
public static DbSelectQuery Select(this DbSelectQuery dbSelectQuery, params Func <DbExpressionFactory, DbExpression>[] expressionSelector)
{
return(Select(dbSelectQuery, DbExpressionFactory.List(expressionSelector.Select(e => e(DbExpressionFactory)))));
}
/// <summary>
/// Specifies the target columns.
/// </summary>
/// <param name="dbInsertQuery">The target <see cref="DbQuery{TQueryExpression}"/>.</param>
/// <param name="columnSelector">A function used to specify the target columns.</param>
/// <returns>A <see cref="DbInsertQuery"/> instance.</returns>
public static DbInsertQuery Columns(this DbInsertQuery dbInsertQuery, params Func <DbExpressionFactory, DbExpression>[] columnSelector)
{
return(Columns(dbInsertQuery, DbExpressionFactory.List(columnSelector.Select(e => e(DbExpressionFactory)))));
}
