Preserve conditional uniqueness in Oracle filtered indexes

docs/_src/content.py

@@ -324,7 +324,7 @@ def page(group, slug, title, summary, *sections, source="src/Migrator/Framework/
 ''', '''
 migration.Delete.Index("IX_Users_Name").FromTable("Users");
 ''')),
-    section("Provider options", '<p>Index definitions also expose IncludeColumns, FilterItems and Clustered. SQL Server (2008+), PostgreSQL and SQLite support filters on any table column, including columns outside KeyColumns. EqualTo or NotEqualTo with null (or DBNull.Value) becomes IS NULL or IS NOT NULL. GetIndexes(table), also available as Schema.Table(table).Indexes() in fluent migrations, reads back the keys, included columns, flags and supported FilterItems. Filters preserve null checks and escaped string values.</p><p>UnsupportedFilterBehavior defaults to UnsupportedIndexFilterBehavior.Throw. Set it to Ignore, or append OnUnsupportedFilter(UnsupportedIndexFilterBehavior.Ignore) in fluent code, to create an unfiltered index on a provider that cannot apply the filters. For unique indexes this enforces uniqueness across all rows. This option only affects unsupported filters; it does not suppress other invalid options or execution failures.</p><p>Oracle retains its limited non-unique, key-column expression emulation and cannot read those expressions back as FilterItems; non-key filters and unique filtered indexes use the chosen unsupported behavior. Oracle rejects included and clustered index requests; SQLite reconstruction rejects existing index SQL with explicit COLLATE clauses.</p><p>The fallback policy is an authoring option and is not stored in database metadata. Preview handles simple indexes and rejects filtered indexes even in Ignore mode.</p>'),
+    section("Provider options", '<p>Index definitions also expose IncludeColumns, FilterItems and Clustered. SQL Server (2008+), PostgreSQL and SQLite support filters on any table column, including columns outside KeyColumns. EqualTo or NotEqualTo with null (or DBNull.Value) becomes IS NULL or IS NOT NULL. GetIndexes(table), also available as Schema.Table(table).Indexes() in fluent migrations, reads back the keys, included columns, flags and supported FilterItems. Filters preserve null checks and escaped string values.</p><p>UnsupportedFilterBehavior defaults to UnsupportedIndexFilterBehavior.Throw. Set it to Ignore, or append OnUnsupportedFilter(UnsupportedIndexFilterBehavior.Ignore) in fluent code, to create an unfiltered index on a provider that cannot apply the filters. For unique indexes this enforces uniqueness across all rows. This option only affects unsupported filters; it does not suppress other invalid options or execution failures.</p><p>Oracle supports filtered unique indexes through functional expressions: every key column uses CASE WHEN with the complete filter predicate, so non-matching rows produce all-NULL keys and are omitted. Filters may reference non-key columns. Oracle retains its limited non-unique, key-column expression emulation and cannot read functional expressions back as FilterItems. Oracle rejects included and clustered index requests; SQLite reconstruction rejects existing index SQL with explicit COLLATE clauses.</p><p>The fallback policy is an authoring option and is not stored in database metadata. Preview handles simple indexes and rejects filtered indexes even in Ignore mode.</p>'),
     section("Unique index or unique constraint?", '<p>Use UniqueConstraint for a table-level invariant and an Index with Unique for an index definition. Do not infer ownership from a generated name. SQLite RemoveAllIndexes preserves declared table UNIQUE constraints; remove those through the constraint APIs. Check query plans and data cardinality when choosing index keys.</p>'), source="src/Migrator/Framework/Index.cs")
 
 page("Schema basics", "constraints", "Keys and constraints", "Declare table invariants independently of column attributes.",