View name override

lib/src/powersync_database.dart

@@ -31,7 +31,7 @@ import 'sync_status.dart';
 /// or not. Once connected, the changes are uploaded.
 class PowerSyncDatabase with SqliteQueries implements SqliteConnection {
   /// Schema used for the local database.
-  final Schema schema;
+  Schema schema;
 
   /// The underlying database.
   ///
@@ -123,6 +123,19 @@ class PowerSyncDatabase with SqliteQueries implements SqliteConnection {
     statusStream = _statusStreamController.stream;
     await database.initialize();
     await migrations.migrate(database);
+    await updateSchema(schema);
+  }
+
+  /// Replace the schema with a new version.
+  /// This is for advanced use cases - typically the schema should just be
+  /// specified once in the constructor.
+  ///
+  /// Cannot be used while connected - this should only be called before [connect].
+  Future<void> updateSchema(Schema schema) async {
+    if (_disconnecter != null) {
+      throw AssertionError('Cannot update schema while connected');
+    }
+    this.schema = schema;
     await updateSchemaInIsolate(database, schema);
   }
 
@@ -144,6 +157,8 @@ class PowerSyncDatabase with SqliteQueries implements SqliteConnection {
   ///
   /// Status changes are reported on [statusStream].
   connect({required PowerSyncBackendConnector connector}) async {
+    await initialize();
+
     // Disconnect if connected
     await disconnect();
     final disconnector = AbortController();
@@ -259,19 +274,23 @@ class PowerSyncDatabase with SqliteQueries implements SqliteConnection {
   ///
   /// The database can still be queried after this is called, but the tables
   /// would be empty.
-  Future<void> disconnectAndClear() async {
+  ///
+  /// To preserve data in local-only tables, set [clearLocal] to false.
+  Future<void> disconnectAndClear({bool clearLocal = true}) async {
     await disconnect();
 
     await writeTransaction((tx) async {
-      await tx.execute('DELETE FROM ps_oplog WHERE 1');
-      await tx.execute('DELETE FROM ps_crud WHERE 1');
-      await tx.execute('DELETE FROM ps_buckets WHERE 1');
+      await tx.execute('DELETE FROM ps_oplog');
+      await tx.execute('DELETE FROM ps_crud');
+      await tx.execute('DELETE FROM ps_buckets');
 
+      final tableGlob = clearLocal ? 'ps_data_*' : 'ps_data__*';
       final existingTableRows = await tx.getAll(
-          "SELECT name FROM sqlite_master WHERE type='table' AND name GLOB 'ps_data_*'");
+          "SELECT name FROM sqlite_master WHERE type='table' AND name GLOB ?",
+          [tableGlob]);
 
       for (var row in existingTableRows) {
-        await tx.execute('DELETE FROM "${row['name']}" WHERE 1');
+        await tx.execute('DELETE FROM ${quoteIdentifier(row['name'])}');
       }
     });
   }

lib/src/schema.dart

@@ -13,7 +13,7 @@ class Schema {
 
 /// A single table in the schema.
 class Table {
-  /// The table name, as used in queries.
+  /// The synced table name, matching sync rules.
   final String name;
 
   /// List of columns.
@@ -28,6 +28,9 @@ class Table {
   /// Whether this is an insert-only table.
   final bool insertOnly;
 
+  /// Override the name for the view
+  final String? _viewNameOverride;
+
   /// Internal use only.
   ///
   /// Name of the table that stores the underlying data.
@@ -42,33 +45,90 @@ class Table {
   /// Create a synced table.
   ///
   /// Local changes are recorded, and remote changes are synced to the local table.
-  const Table(this.name, this.columns, {this.indexes = const []})
-      : localOnly = false,
-        insertOnly = false;
+  const Table(this.name, this.columns,
+      {this.indexes = const [], String? viewName, this.localOnly = false})
+      : insertOnly = false,
+        _viewNameOverride = viewName;
 
   /// Create a table that only exists locally.
   ///
   /// This table does not record changes, and is not synchronized from the service.
-  const Table.localOnly(this.name, this.columns, {this.indexes = const []})
+  const Table.localOnly(this.name, this.columns,
+      {this.indexes = const [], String? viewName})
       : localOnly = true,
-        insertOnly = false;
+        insertOnly = false,
+        _viewNameOverride = viewName;
 
   /// Create a table that only supports inserts.
   ///
   /// This table records INSERT statements, but does not persist data locally.
   ///
   /// SELECT queries on the table will always return 0 rows.
-  const Table.insertOnly(this.name, this.columns)
+  const Table.insertOnly(this.name, this.columns, {String? viewName})
       : localOnly = false,
         insertOnly = true,
-        indexes = const [];
+        indexes = const [],
+        _viewNameOverride = viewName;
 
   Column operator [](String columnName) {
     return columns.firstWhere((element) => element.name == columnName);
   }
 
   bool get validName {
-    return !invalidSqliteCharacters.hasMatch(name);
+    return !invalidSqliteCharacters.hasMatch(name) &&
+        (_viewNameOverride == null ||
+            !invalidSqliteCharacters.hasMatch(_viewNameOverride!));
+  }
+
+  /// Check that there are no issues in the table definition.
+  void validate() {
+    if (invalidSqliteCharacters.hasMatch(name)) {
+      throw AssertionError("Invalid characters in table name: $name");
+    } else if (_viewNameOverride != null &&
+        invalidSqliteCharacters.hasMatch(_viewNameOverride!)) {
+      throw AssertionError(
+          "Invalid characters in view name: $_viewNameOverride");
+    }
+
+    Set<String> columnNames = {"id"};
+    for (var column in columns) {
+      if (column.name == 'id') {
+        throw AssertionError(
+            "$name: id column is automatically added, custom id columns are not supported");
+      } else if (columnNames.contains(column.name)) {
+        throw AssertionError("Duplicate column $name.${column.name}");
+      } else if (invalidSqliteCharacters.hasMatch(column.name)) {
+        throw AssertionError(
+            "Invalid characters in column name: $name.${column.name}");
+      }
+
+      columnNames.add(column.name);
+    }
+    Set<String> indexNames = {};
+
+    for (var index in indexes) {
+      if (indexNames.contains(index.name)) {
+        throw AssertionError("Duplicate index $name.${index.name}");
+      } else if (invalidSqliteCharacters.hasMatch(index.name)) {
+        throw AssertionError(
+            "Invalid characters in index name: $name.${index.name}");
+      }
+
+      for (var column in index.columns) {
+        if (!columnNames.contains(column.column)) {
+          throw AssertionError(
+              "Column $name.${column.column} not found for index ${index.name}");
+        }
+      }
+
+      indexNames.add(index.name);
+    }
+  }
+
+  /// Name for the view, used for queries.
+  /// Defaults to the synced table name.
+  String get viewName {
+    return _viewNameOverride ?? name;
   }
 }
 

lib/src/schema_logic.dart

@@ -16,10 +16,10 @@ String createViewStatement(Table table) {
 
   if (table.insertOnly) {
     final nulls = table.columns.map((column) => 'NULL').join(', ');
-    return 'CREATE VIEW ${quoteIdentifier(table.name)}("id", $columnNames) AS SELECT NULL, $nulls WHERE 0 $_autoGenerated';
+    return 'CREATE VIEW ${quoteIdentifier(table.viewName)}("id", $columnNames) AS SELECT NULL, $nulls WHERE 0 $_autoGenerated';
   }
   final select = table.columns.map(mapColumn).join(', ');
-  return 'CREATE VIEW ${quoteIdentifier(table.name)}("id", $columnNames) AS SELECT "id", $select FROM ${quoteIdentifier(table.internalName)} $_autoGenerated';
+  return 'CREATE VIEW ${quoteIdentifier(table.viewName)}("id", $columnNames) AS SELECT "id", $select FROM ${quoteIdentifier(table.internalName)} $_autoGenerated';
 }
 
 String mapColumn(Column column) {
@@ -32,6 +32,7 @@ List<String> createViewTriggerStatements(Table table) {
   } else if (table.insertOnly) {
     return createViewTriggerStatementsInsert(table);
   }
+  final viewName = table.viewName;
   final type = table.name;
   final internalNameE = quoteIdentifier(table.internalName);
 
@@ -46,16 +47,16 @@ List<String> createViewTriggerStatements(Table table) {
   // Names in alphabetical order
   return [
     """
-CREATE TRIGGER ${quoteIdentifier('ps_view_delete_$type')}
-INSTEAD OF DELETE ON ${quoteIdentifier(type)}
+CREATE TRIGGER ${quoteIdentifier('ps_view_delete_$viewName')}
+INSTEAD OF DELETE ON ${quoteIdentifier(viewName)}
 FOR EACH ROW
 BEGIN
   DELETE FROM $internalNameE WHERE id = OLD.id;
   INSERT INTO ps_crud(tx_id, data) SELECT current_tx, json_object('op', 'DELETE', 'type', ${quoteString(type)}, 'id', OLD.id) FROM ps_tx WHERE id = 1;
 END""",
     """
-CREATE TRIGGER ${quoteIdentifier('ps_view_insert_$type')}
-INSTEAD OF INSERT ON ${quoteIdentifier(type)}
+CREATE TRIGGER ${quoteIdentifier('ps_view_insert_$viewName')}
+INSTEAD OF INSERT ON ${quoteIdentifier(viewName)}
 FOR EACH ROW
 BEGIN
   SELECT CASE
@@ -76,8 +77,8 @@ BEGIN
   INSERT OR REPLACE INTO ps_buckets(name, pending_delete, last_op, target_op) VALUES('\$local', 1, 0, $maxOpId);
 END""",
     """
-CREATE TRIGGER ${quoteIdentifier('ps_view_update_$type')}
-INSTEAD OF UPDATE ON ${quoteIdentifier(type)}
+CREATE TRIGGER ${quoteIdentifier('ps_view_update_$viewName')}
+INSTEAD OF UPDATE ON ${quoteIdentifier(viewName)}
 FOR EACH ROW
 BEGIN
   SELECT CASE
@@ -102,7 +103,7 @@ END"""
 }
 
 List<String> createViewTriggerStatementsLocal(Table table) {
-  final type = table.name;
+  final viewName = table.viewName;
   final internalNameE = quoteIdentifier(table.internalName);
 
   final jsonFragment = table.columns
@@ -112,23 +113,23 @@ List<String> createViewTriggerStatementsLocal(Table table) {
   // Names in alphabetical order
   return [
     """
-CREATE TRIGGER ${quoteIdentifier('ps_view_delete_$type')}
-INSTEAD OF DELETE ON ${quoteIdentifier(type)}
+CREATE TRIGGER ${quoteIdentifier('ps_view_delete_$viewName')}
+INSTEAD OF DELETE ON ${quoteIdentifier(viewName)}
 FOR EACH ROW
 BEGIN
   DELETE FROM $internalNameE WHERE id = OLD.id;
 END""",
     """
-CREATE TRIGGER ${quoteIdentifier('ps_view_insert_$type')}
-INSTEAD OF INSERT ON ${quoteIdentifier(type)}
+CREATE TRIGGER ${quoteIdentifier('ps_view_insert_$viewName')}
+INSTEAD OF INSERT ON ${quoteIdentifier(viewName)}
 FOR EACH ROW
 BEGIN
   INSERT INTO $internalNameE(id, data)
     SELECT NEW.id, json_object($jsonFragment);
 END""",
     """
-CREATE TRIGGER ${quoteIdentifier('ps_view_update_$type')}
-INSTEAD OF UPDATE ON ${quoteIdentifier(type)}
+CREATE TRIGGER ${quoteIdentifier('ps_view_update_$viewName')}
+INSTEAD OF UPDATE ON ${quoteIdentifier(viewName)}
 FOR EACH ROW
 BEGIN
   SELECT CASE
@@ -144,15 +145,16 @@ END"""
 
 List<String> createViewTriggerStatementsInsert(Table table) {
   final type = table.name;
+  final viewName = table.viewName;
 
   final jsonFragment = table.columns
       .map((column) =>
           "${quoteString(column.name)}, NEW.${quoteIdentifier(column.name)}")
       .join(', ');
   return [
     """
-CREATE TRIGGER ${quoteIdentifier('ps_view_insert_$type')}
-INSTEAD OF INSERT ON ${quoteIdentifier(type)}
+CREATE TRIGGER ${quoteIdentifier('ps_view_insert_$viewName')}
+INSTEAD OF INSERT ON ${quoteIdentifier(viewName)}
 FOR EACH ROW
 BEGIN
   INSERT INTO ps_crud(tx_id, data) SELECT current_tx, json_object('op', 'PUT', 'type', ${quoteString(type)}, 'id', NEW.id, 'data', json(powersync_diff('{}', json_object($jsonFragment)))) FROM ps_tx WHERE id = 1;
@@ -164,6 +166,10 @@ END"""
 ///
 /// Must be wrapped in a transaction.
 void updateSchema(sqlite.Database db, Schema schema) {
+  for (var table in schema.tables) {
+    table.validate();
+  }
+
   _createTablesAndIndexes(db, schema);
 
   final existingViewRows = db.select(
@@ -172,8 +178,6 @@ void updateSchema(sqlite.Database db, Schema schema) {
   Set<String> toRemove = {for (var row in existingViewRows) row['name']};
 
   for (var table in schema.tables) {
-    assert(table.validName, "Invalid characters in table name: ${table.name}");
-
     toRemove.remove(table.name);
 
     var createViewOp = createViewStatement(table);