/// <summary>
 /// Constructs an SQLiteDataSourceFilterExpressionVisitor providing an alternative literal emitter.
 /// </summary>
 /// <param name="literalEmitter">An alternative literal emitter to use.</param>
 public SQLiteDataSourceFilterExpressionVisitor(TableMapping mappings, ISQLiteLiteralEmitter literalEmitter)
     : this(mappings)
 {
     _literalEmitter = literalEmitter;
 }
 /// <summary>
 /// Constructs an SQLiteDataSourceFilterExpressionVisitor.
 /// </summary>
 public SQLiteDataSourceFilterExpressionVisitor(TableMapping mappings)
 {
     _mappings       = mappings;
     _literalEmitter = new DefaultSQLiteLiteralEmitter();
     _sb             = new StringBuilder();
 }