presto-redis/src/main/java/io/prestosql/plugin/redis/RedisMetadata.java/RedisMetadata/getTableMetadata
class RedisMetadata:    @Nullable
    private ConnectorTableMetadata getTableMetadata(SchemaTableName schemaTableName)
    {
        RedisTableDescription table = getDefinedTables().get(schemaTableName);
        if (table == null) {
            return null;
        }

        ImmutableList.Builder<ColumnMetadata> builder = ImmutableList.builder();

        appendFields(builder, table.getKey());
        appendFields(builder, table.getValue());

        for (RedisInternalFieldDescription fieldDescription : RedisInternalFieldDescription.values()) {
            builder.add(fieldDescription.getColumnMetadata(hideInternalColumns));
        }

        return new ConnectorTableMetadata(schemaTableName, builder.build());
    }