Docs: MIgrate user version when encrypting existing databases

Author: simolus3

docs/lib/snippets/modular/many_to_many/json.drift.dart

@@ -174,8 +174,6 @@ class $ShoppingCartsTable extends i3.ShoppingCarts
  requiredDuringInsert: false,
  defaultConstraints:
  i0.GeneratedColumn.constraintIsAlways('PRIMARY KEY AUTOINCREMENT'));
- static const i0.VerificationMeta _entriesMeta =
- const i0.VerificationMeta('entries');
  @override
  late final i0.GeneratedColumnWithTypeConverter<i3.ShoppingCartEntries, String>
  entries = i0.GeneratedColumn<String>('entries', aliasedName, false,
@@ -198,7 +196,6 @@ class $ShoppingCartsTable extends i3.ShoppingCarts
  if (data.containsKey('id')) {
  context.handle(_idMeta, id.isAcceptableOrUnknown(data['id']!, _idMeta));
  }
- context.handle(_entriesMeta, const i0.VerificationResult.success());
  return context;
  }
 

docs/lib/snippets/platforms/encryption.dart

@@ -78,10 +78,18 @@ void databases() {
 
  if (await existing.exists() && !await encrypted.exists()) {
  // We have an existing database to migrate.
- sqlite3.open(existingDatabasePath)
+ final plaintextDb = sqlite3.open(existingDatabasePath)
  ..execute("ATTACH DATABASE '${escapeString(encryptedDatabasePath)}' "
  "AS encrypted KEY '${escapeString(yourKey)}';")
- ..execute("SELECT sqlcipher_export('encrypted');")
+ ..execute("SELECT sqlcipher_export('encrypted');");
+
+ // sqlcipher_export doesn't apply the user_version pragma used by drift
+ // to implement migrations. The version of the encrypted database must
+ // match the previous state.
+ final userVersion =
+ plaintextDb.select('PRAGMA user_version;').first.columnAt(0) as int;
+ plaintextDb
+ ..execute('PRAGMA encrypted.user_version = $userVersion;')
  ..execute('DETACH DATABASE encrypted;')
  ..dispose();