Manage OR REPLACE cases in VIEW creation

Signed-off-by: Alejandro García Montoro <alejandro.garciamontoro@gmail.com>

Author: agarciamontoro

sql/parse/views.go

@@ -53,6 +53,11 @@ func parseCreateView(ctx *sql.Context, s string) (sql.Node, error) {
 		return nil, ErrMalformedViewName.New(strings.Join(scopedName, "."))
 	}
 
+	// TODO(agarciamontoro): Add support for explicit column names
+	if len(columns) != 0 {
+		return nil, ErrUnsupportedSyntax.New("the view creation must not specify explicit column names")
+	}
+
 	if len(scopedName) == 1 {
 		viewName = scopedName[0]
 	}
@@ -79,6 +84,6 @@ func parseCreateView(ctx *sql.Context, s string) (sql.Node, error) {
 	subqueryAlias := plan.NewSubqueryAlias(viewName, subqueryNode)
 
 	return plan.NewCreateView(
-		sql.UnresolvedDatabase(databaseName), viewName, columns, subqueryAlias,
+		sql.UnresolvedDatabase(databaseName), viewName, columns, subqueryAlias, isReplace,
 	), nil
 }

sql/plan/create_view.go

@@ -13,20 +13,23 @@ type CreateView struct {
 	Name     string
 	Columns  []string
 	Catalog  *sql.Catalog
+	IsReplace bool
 }
 
 func NewCreateView(
 	database sql.Database,
 	name string,
 	columns []string,
 	definition *SubqueryAlias,
+	isReplace bool,
 ) *CreateView {
 	return &CreateView{
 		UnaryNode{Child: definition},
 		database,
 		name,
 		columns,
 		nil,
+		isReplace,
 	}
 }
 
@@ -45,6 +48,10 @@ func (create *CreateView) Resolved() bool {
 func (create *CreateView) RowIter(ctx *sql.Context) (sql.RowIter, error) {
 	view := sql.View{create.Name, create.Child}
 
+	if create.IsReplace {
+		_ = create.Catalog.ViewRegistry.Delete(create.database.Name(), view.Name)
+	}
+
 	return sql.RowsToRowIter(), create.Catalog.ViewRegistry.Register(create.database.Name(), view)
 }