/// <summary>
/// Translates the <paramref name="deleteExpression"/> into a string representation.
/// </summary>
/// <param name="deleteExpression">The <see cref="DbDeleteExpression"/> to translate.</param>
/// <returns><see cref="string"/></returns>
protected override DbExpression VisitDeleteExpression(DbDeleteExpression deleteExpression)
{
var sb = new StringBuilder();
if (deleteExpression.FromExpression.IsNull())
{
sb.AppendFormat("DELETE FROM {0} ", Visit(deleteExpression.Target));
}
else
{
var aliasExpression = deleteExpression.FromExpression.Find <DbAliasExpression>(ae => ae.Target.Equals(deleteExpression.Target)).FirstOrDefault();
if (aliasExpression.IsNull())
{
sb.AppendFormat("DELETE {0} ", Visit(deleteExpression.Target));
}
else
{
sb.AppendFormat("DELETE {0} ", aliasExpression.Alias);
}
sb.AppendLine();
sb.AppendLine("FROM ");
sb.AppendFormat(1, "{0} ", Visit(deleteExpression.FromExpression));
}
if (!deleteExpression.WhereExpression.IsNull())
{
sb.AppendLine();
sb.AppendLine("WHERE ");
sb.AppendFormat(1, "{0} ", Visit(deleteExpression.WhereExpression));
}
return(ExpressionFactory.Sql(sb.ToString().Trim()));
}
/// <summary>
/// Translates the <paramref name="deleteExpression"/> into a string representation.
/// </summary>
/// <param name="deleteExpression">The <see cref="DbDeleteExpression"/> to translate.</param>
/// <returns><see cref="DbExpression"/></returns>
protected virtual DbExpression VisitDeleteExpression(DbDeleteExpression deleteExpression)
{
var targetExpression = Visit(deleteExpression.Target);
var fromExpression = Visit(deleteExpression.FromExpression);
var whereExpression = Visit(deleteExpression.WhereExpression);
if (!ReferenceEquals(targetExpression, deleteExpression.Target) ||
!ReferenceEquals(fromExpression, deleteExpression.FromExpression) ||
!ReferenceEquals(whereExpression, deleteExpression.WhereExpression))
{
return(ExpressionFactory.Delete(targetExpression, fromExpression, whereExpression));
}
return(deleteExpression);
}
/// <summary>
/// Translates the <paramref name="deleteExpression"/> into a string representation.
/// </summary>
/// <param name="deleteExpression">The <see cref="DbDeleteExpression"/> to translate.</param>
/// <returns><see cref="string"/></returns>
protected override DbExpression VisitDeleteExpression(DbDeleteExpression deleteExpression)
{
var sb = new StringBuilder();
if (deleteExpression.FromExpression.IsNull())
{
sb.AppendFormat("DELETE FROM {0} ", Visit(deleteExpression.Target));
}
else
{
var aliasExpression = deleteExpression.FromExpression.Find<DbAliasExpression>(ae => ae.Target.Equals(deleteExpression.Target)).FirstOrDefault();
if (aliasExpression.IsNull())
sb.AppendFormat("DELETE {0} ", Visit(deleteExpression.Target));
else
sb.AppendFormat("DELETE {0} ", aliasExpression.Alias);
sb.AppendLine();
sb.AppendLine("FROM ");
sb.AppendFormat(1, "{0} ", Visit(deleteExpression.FromExpression));
}
if (!deleteExpression.WhereExpression.IsNull())
{
sb.AppendLine();
sb.AppendLine("WHERE ");
sb.AppendFormat(1, "{0} ", Visit(deleteExpression.WhereExpression));
}
return ExpressionFactory.Sql(sb.ToString().Trim());
}
/// <summary>
/// Creates a new <see cref="DbDeleteExpression"/> that represents delete statement.
/// </summary>
/// <param name="target">The <see cref="DbExpression"/> that represents the delete target.</param>
/// <param name="fromExpression">The <see cref="DbExpression"/> that represents the 'FROM' clause of the query.</param>
/// <param name="whereExpression">the <see cref="DbExpression"/> that represents the 'WHERE' clause of the query.</param>
/// <returns>A <see cref="DbDeleteExpression"/> instance.</returns>
public DbDeleteExpression Delete(DbExpression target, DbExpression fromExpression, DbExpression whereExpression)
{
var dbDeleteExpression = new
DbDeleteExpression
{
Target = target,
FromExpression = fromExpression,
WhereExpression = whereExpression
};
return dbDeleteExpression;
}
/// <summary>
/// Translates the <paramref name="deleteExpression"/> into a string representation.
/// </summary>
/// <param name="deleteExpression">The <see cref="DbDeleteExpression"/> to translate.</param>
/// <returns><see cref="DbExpression"/></returns>
protected virtual DbExpression VisitDeleteExpression(DbDeleteExpression deleteExpression)
{
var targetExpression = Visit(deleteExpression.Target);
var fromExpression = Visit(deleteExpression.FromExpression);
var whereExpression = Visit(deleteExpression.WhereExpression);
if (!ReferenceEquals(targetExpression,deleteExpression.Target) ||
!ReferenceEquals(fromExpression,deleteExpression.FromExpression) ||
!ReferenceEquals(whereExpression,deleteExpression.WhereExpression))
{
return ExpressionFactory.Delete(targetExpression, fromExpression, whereExpression);
}
return deleteExpression;
}
