Modified create_views to support materialized views (#538)

Co-authored-by: Barry Daniels <[email protected]>
Amsterdam · Jan 12, 2024 · 4cf51d9 · 4cf51d9
1 parent 065c44e
commit 4cf51d9
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Showing 3 changed files with 13 additions and 11 deletions.
diff --git a/CHANGES.md b/CHANGES.md
@@ -1,3 +1,7 @@
+# 2024-01-12 (5.23.0)
+
+* Modified create_views functions to support materialized views
+
 # 2024-01-10 (5.22.0)
 
 * Add `enable_export` column to the `dataset` model to be able

diff --git a/setup.cfg b/setup.cfg
@@ -1,6 +1,6 @@
 [metadata]
 name = amsterdam-schema-tools
-version = 5.22.0
+version = 5.23.0
 url = https://github.com/amsterdam/schema-tools
 license = Mozilla Public 2.0
 author = Team Data Diensten, van het Dataplatform onder de Directie Digitale Voorzieningen (Gemeente Amsterdam)

diff --git a/src/schematools/contrib/django/management/commands/create_views.py b/src/schematools/contrib/django/management/commands/create_views.py
@@ -34,11 +34,6 @@ def _is_valid_sql(view_sql: str, view_name: str, write_role_name: str) -> bool:
                     )
                 )
 
-                cursor.execute(
-                    sql.SQL("DROP VIEW IF EXISTS {view_name} CASCADE").format(
-                        view_name=sql.Identifier(view_name)
-                    )
-                )
                 cursor.execute(view_sql)
             transaction.savepoint_rollback(sid)
     except Exception as e:  # noqa: F841
@@ -135,7 +130,6 @@ def create_views(
         for table in dataset.schema.tables:
             if table.is_view:
                 command.stdout.write(f"* Creating view {table.db_name}")
-
                 # Generate the write role name
                 write_role_name = f"write_{table._parent_schema.db_name}"
 
@@ -200,11 +194,15 @@ def create_views(
                             )
 
                             # Remove the view if it exists
-                            cursor.execute(
-                                sql.SQL("DROP VIEW IF EXISTS {view_name} CASCADE").format(
-                                    view_name=sql.Identifier(table.db_name)
+                            # Due to the large costs of recreating materialized views, we only create
+                            # and not drop them. When changes are made to the materialized view the view
+                            # must be droped manually.
+                            if "materialized" not in view_sql.lower():
+                                cursor.execute(
+                                    sql.SQL("DROP VIEW IF EXISTS {view_name} CASCADE").format(
+                                        view_name=sql.Identifier(table.db_name)
+                                    )
                                 )
-                            )
 
                             # Create the view
                             cursor.execute(view_sql)