index method
Adds a named index (executed as a separate statement after CREATE TABLE). Note: This generates a separate SQL statement, stored for later execution.
Implementation
String index(String name, List<String> columns) {
final cols = columns.map((c) => '"${Schema._sanitize(c)}"').join(', ');
return 'CREATE INDEX "${Schema._sanitize(name)}" ON "${Schema._sanitize(_table)}" ($cols)';
}