presto-redis/src/main/java/io/prestosql/plugin/redis/RedisRecordCursor.java/RedisRecordCursor/setScanParms
class RedisRecordCursor:    private ScanParams setScanParms()
    {
        if (split.getKeyDataType() == RedisDataType.STRING) {
            ScanParams scanParms = new ScanParams();
            scanParms.count(redisJedisManager.getRedisConnectorConfig().getRedisScanCount());

            // when Redis key string follows "schema:table:*" format
            // scan command can efficiently query tables
            // by returning matching keys
            // the alternative is to set key-prefix-schema-table to false
            // and treat entire redis as single schema , single table
            // redis Hash/Set types are to be supported - they can also be
            // used to filter out table data

            // "default" schema is not prefixed to the key

            if (redisJedisManager.getRedisConnectorConfig().isKeyPrefixSchemaTable()) {
                String keyMatch = "";
                if (!split.getSchemaName().equals("default")) {
                    keyMatch = split.getSchemaName() + Character.toString(redisJedisManager.getRedisConnectorConfig().getRedisKeyDelimiter());
                }
                keyMatch = keyMatch + split.getTableName() + Character.toString(redisJedisManager.getRedisConnectorConfig().getRedisKeyDelimiter()) + "*";
                scanParms.match(keyMatch);
            }
            return scanParms;
        }

        return null;
    }