Iceberg Catalog

使用限制

支持 Iceberg V1/V2 表格式。
V2 格式仅支持 Position Delete 方式，不支持 Equality Delete。
支持 Parquet 文件格式。

创建 Catalog

基于 Hive Metastore 创建 Catalog

和 Hive Catalog 基本一致，这里仅给出简单示例。其他示例可参阅 Hive Catalog。

CREATE CATALOG iceberg PROPERTIES (
    'type'='hms',
    'hive.metastore.uris' = 'thrift://172.21.0.1:7004',
    'hadoop.username' = 'hive',
    'dfs.nameservices'='your-nameservice',
    'dfs.ha.namenodes.your-nameservice'='nn1,nn2',
    'dfs.namenode.rpc-address.your-nameservice.nn1'='172.21.0.2:4007',
    'dfs.namenode.rpc-address.your-nameservice.nn2'='172.21.0.3:4007',
    'dfs.client.failover.proxy.provider.your-nameservice'='org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider'
);

基于 Iceberg API 创建 Catalog

使用 Iceberg API 访问元数据的方式，支持 Hadoop File System、Hive、REST、Glue、DLF 等服务作为 Iceberg 的 Catalog。

Hadoop Catalog

CREATE CATALOG iceberg_hadoop PROPERTIES (
    'type'='iceberg',
    'iceberg.catalog.type' = 'hadoop',
    'warehouse' = 'hdfs://your-host:8020/dir/key'
);

CREATE CATALOG iceberg_hadoop_ha PROPERTIES (
    'type'='iceberg',
    'iceberg.catalog.type' = 'hadoop',
    'warehouse' = 'hdfs://your-nameservice/dir/key',
    'dfs.nameservices'='your-nameservice',
    'dfs.ha.namenodes.your-nameservice'='nn1,nn2',
    'dfs.namenode.rpc-address.your-nameservice.nn1'='172.21.0.2:4007',
    'dfs.namenode.rpc-address.your-nameservice.nn2'='172.21.0.3:4007',
    'dfs.client.failover.proxy.provider.your-nameservice'='org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider'
);

Hive Metastore

CREATE CATALOG iceberg PROPERTIES (
    'type'='iceberg',
    'iceberg.catalog.type'='hms',
    'hive.metastore.uris' = 'thrift://172.21.0.1:7004',
    'hadoop.username' = 'hive',
    'dfs.nameservices'='your-nameservice',
    'dfs.ha.namenodes.your-nameservice'='nn1,nn2',
    'dfs.namenode.rpc-address.your-nameservice.nn1'='172.21.0.2:4007',
    'dfs.namenode.rpc-address.your-nameservice.nn2'='172.21.0.3:4007',
    'dfs.client.failover.proxy.provider.your-nameservice'='org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider'
);

AWS Glue

CREATE CATALOG glue PROPERTIES (
    "type"="iceberg",
    "iceberg.catalog.type" = "glue",
    "glue.endpoint" = "https://glue.us-east-1.amazonaws.com",
    "glue.access_key" = "ak",
    "glue.secret_key" = "sk"
);

Iceberg 属性详情参见 Iceberg Glue Catalog

阿里云 DLF

参见阿里云 DLF Catalog 配置

REST Catalog

该方式需要预先提供 REST 服务，用户需实现获取 Iceberg 元数据的 REST 接口。

CREATE CATALOG iceberg PROPERTIES (
    'type'='iceberg',
    'iceberg.catalog.type'='rest',
    'uri' = 'http://172.21.0.1:8181'
);

如果使用 HDFS 存储数据，并开启了高可用模式，还需在 Catalog 中增加 HDFS 高可用配置：

CREATE CATALOG iceberg PROPERTIES (
    'type'='iceberg',
    'iceberg.catalog.type'='rest',
    'uri' = 'http://172.21.0.1:8181',
    'dfs.nameservices'='your-nameservice',
    'dfs.ha.namenodes.your-nameservice'='nn1,nn2',
    'dfs.namenode.rpc-address.your-nameservice.nn1'='172.21.0.1:8020',
    'dfs.namenode.rpc-address.your-nameservice.nn2'='172.21.0.2:8020',
    'dfs.client.failover.proxy.provider.your-nameservice'='org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider'
);

Google Dataproc Metastore

CREATE CATALOG iceberg PROPERTIES (
    "type"="iceberg",
    "iceberg.catalog.type"="hms",
    "hive.metastore.uris" = "thrift://172.21.0.1:9083",
    "gs.endpoint" = "https://storage.googleapis.com",
    "gs.region" = "us-east-1",
    "gs.access_key" = "ak",
    "gs.secret_key" = "sk",
    "use_path_style" = "true"
);

hive.metastore.uris: Dataproc Metastore 服务开放的接口，在 Metastore 管理页面获取：Dataproc Metastore Services.

Iceberg On Object Storage

若数据存放在 S3 上，properties 中可以使用以下参数：

"s3.access_key" = "ak"
"s3.secret_key" = "sk"
"s3.endpoint" = "s3.us-east-1.amazonaws.com"
"s3.region" = "us-east-1"

数据存放在阿里云 OSS 上：

"oss.access_key" = "ak"
"oss.secret_key" = "sk"
"oss.endpoint" = "oss-cn-beijing-internal.aliyuncs.com"
"oss.region" = "oss-cn-beijing"

数据存放在腾讯云 COS 上：

"cos.access_key" = "ak"
"cos.secret_key" = "sk"
"cos.endpoint" = "cos.ap-beijing.myqcloud.com"
"cos.region" = "ap-beijing"

数据存放在华为云 OBS 上：

"obs.access_key" = "ak"
"obs.secret_key" = "sk"
"obs.endpoint" = "obs.cn-north-4.myhuaweicloud.com"
"obs.region" = "cn-north-4"

列类型映射

Iceberg Type	Doris Type
boolean	boolean
int	int
long	bigint
float	float
double	double
decimal(p,s)	decimal(p,s)
date	date
uuid	string
timestamp (Timestamp without timezone)	datetime(6)
timestamptz (Timestamp with timezone)	datetime(6)
string	string
fixed(L)	char(L)
binary	string
list	array
struct	不支持
map	不支持
time	不支持

Time Travel

支持读取 Iceberg 表指定的 Snapshot。

每一次对 iceberg 表的写操作都会产生一个新的快照。

默认情况下，读取请求只会读取最新版本的快照。

可以使用 FOR TIME AS OF 和 FOR VERSION AS OF 语句，根据快照 ID 或者快照产生的时间读取历史版本的数据。示例如下：

SELECT * FROM iceberg_tbl FOR TIME AS OF "2022-10-07 17:20:37";

SELECT * FROM iceberg_tbl FOR VERSION AS OF 868895038966572;

另外，可以使用 iceberg_meta 表函数查询指定表的 snapshot 信息。

使用限制​

创建 Catalog​

基于 Hive Metastore 创建 Catalog​

基于 Iceberg API 创建 Catalog​

Iceberg On Object Storage​

列类型映射​

Time Travel​