public void Execute(IEnumerable <DatabaseView> baseViews, IEnumerable <DatabaseView> compareViews)
{
bool first = false;
//find new views (in compare, but not in base)
foreach (var view in compareViews)
{
var name = view.Name;
var schema = view.SchemaOwner;
var match = baseViews.FirstOrDefault(t => t.Name == name && t.SchemaOwner == schema);
if (match != null)
{
continue;
}
var script = string.Empty;
if (!first)
{
first = true;
//CREATE VIEW cannot be combined with other statements in a batch, so be preceeded by and terminate with a "GO" (sqlServer) or "/" (Oracle)
if (_results.Count > 0)
{
script += _writer.RunStatements() + Environment.NewLine;
}
}
script += "-- NEW VIEW " + view.Name + Environment.NewLine +
_writer.AddView(view);
CreateResult(ResultType.Add, view, script);
}
//find dropped and existing views
foreach (var view in baseViews)
{
var name = view.Name;
var schema = view.SchemaOwner;
var match = compareViews.FirstOrDefault(t => t.Name == name && t.SchemaOwner == schema);
if (match == null)
{
CreateResult(ResultType.Delete, view,
"-- DROP VIEW " + view.Name + Environment.NewLine +
_writer.DropView(view));
continue;
}
//view may or may not have been changed
//we require the view Sql (otherwise we can't write it)
if (view.Sql == match.Sql)
{
continue; //the same
}
//a sanitized comparison
if (_writer.CompareView(view.Sql, match.Sql))
{
continue;
}
//in Oracle could be a CREATE OR REPLACE
var script = "-- ALTER VIEW " + view.Name + Environment.NewLine +
_writer.DropView(view) + Environment.NewLine +
_writer.AddView(match);
CreateResult(ResultType.Change, view, script);
}
}
