doris 2.1.6 关于bloom_filter_columns

Viewed 28

CREATE TABLE dwd_ess_cell_inc (
time datetime NOT NULL COMMENT '采集时间戳',
namespace_code varchar(64) NOT NULL COMMENT '项目英文名',
device_instance_property_code varchar(64) NOT NULL COMMENT '属性英文名',
device_instance_code varchar(64) NOT NULL COMMENT '唯一映射key (instanceCode)',
value varchar(64) NULL COMMENT '值',
create_time datetime NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间'
) ENGINE=OLAP
UNIQUE KEY(time, namespace_code, device_instance_property_code, device_instance_code)
COMMENT 'DWD|储能数仓|电芯数据明细表'
PARTITION BY RANGE(time)()
DISTRIBUTED BY HASH(time, namespace_code, device_instance_property_code, device_instance_code) BUCKETS 10
PROPERTIES (
"replication_allocation" = "tag.location.default: 3",
"min_load_replica_num" = "-1",
"bloom_filter_columns" = "namespace_code",
"is_being_synced" = "false",
"dynamic_partition.enable" = "true",
"dynamic_partition.time_unit" = "MONTH",
"dynamic_partition.time_zone" = "Asia/Shanghai",
"dynamic_partition.start" = "-36",
"dynamic_partition.end" = "3",
"dynamic_partition.prefix" = "p",
"dynamic_partition.replication_allocation" = "tag.location.default: 3",
"dynamic_partition.buckets" = "36",
"dynamic_partition.create_history_partition" = "true",
"dynamic_partition.history_partition_num" = "36",
"dynamic_partition.hot_partition_num" = "0",
"dynamic_partition.reserved_history_periods" = "NULL",
"dynamic_partition.storage_policy" = "",
"dynamic_partition.start_day_of_month" = "1",
"storage_medium" = "hdd",
"storage_format" = "V2",
"inverted_index_storage_format" = "V1",
"enable_unique_key_merge_on_write" = "false",
"light_schema_change" = "true",
"disable_auto_compaction" = "false",
"enable_single_replica_compaction" = "false",
"group_commit_interval_ms" = "10000",
"group_commit_data_bytes" = "134217728"
);

这种表结构下,bloom_filter_columns有没有起到有效索引作用,会不会增加写入压力

1 Answers

一般不会增加写入压力;
可以通过profile的RowsBloomFilterFiltered属性进行确定:Query Profile