Implement word search

lib/_data_ingestion/sql_writable.dart

@@ -1,5 +1,11 @@
+/// Interface for objects which are meant to be written to a table in a SQL database.
 abstract class SQLWritable {
   const SQLWritable();
 
+  /// Returns a map of the object's properties and their values.
+  /// 
+  /// Note that there might be properties in the object which is meant to be
+  /// inserted into a different table. These properties will/should be excluded
+  /// from this map.
   Map<String, Object?> get sqlValue;
 }