rmoff / flink-iceberg-hive

Apache Flink writing to Apache Iceberg on S3 (MinIO) using Apache Hive Metastore

Launch stack

docker compose build
docker compose up

Run SQL Client

docker compose exec -it flink ./bin/sql-client.sh

Do SQL Stuff

CREATE CATALOG c_iceberg_hive WITH (
        'type' = 'iceberg',
        'catalog-type'='hive',
        'warehouse' = 's3a://warehouse',
        'hive-conf-dir' = './conf');

CREATE DATABASE `c_iceberg_hive`.`db01`;

USE `c_iceberg_hive`.`db01`;

CREATE TABLE t_foo (c1 varchar, c2 int);

INSERT INTO t_foo VALUES ('a',42);

SET 'execution.runtime-mode' = 'batch';
SET 'sql-client.execution.result-mode' = 'tableau';

-- Wait a few moments; running this straightaway often doesn't show
-- the results
SELECT * FROM t_foo;

Poke around

Flink Dashboard: http://localhost:8081/

MinIO (login admin/password): http://localhost:9001/browser/warehouse/

Logs from Flink

docker compose exec -t flink bash -c "tail -f log/*"

MinIO Contents

❯ docker compose exec mc bash -c "mc ls -r minio/warehouse/"
[2024-02-02 21:30:22 UTC]   608B STANDARD db01.db/t_foo/data/00000-0-41e6f635-3859-46ef-a57e-de5f774203fa-00001.parquet
[2024-02-02 21:30:08 UTC]   957B STANDARD db01.db/t_foo/metadata/00000-109580b8-77eb-45d5-b2a7-bd63bd239c99.metadata.json
[2024-02-02 21:30:23 UTC] 2.1KiB STANDARD db01.db/t_foo/metadata/00001-e5705f33-a446-4614-ba66-80a40e176318.metadata.json
[2024-02-02 21:30:23 UTC] 6.5KiB STANDARD db01.db/t_foo/metadata/3485210c-2c99-4c72-bb36-030c8e0a4a90-m0.avro
[2024-02-02 21:30:23 UTC] 4.2KiB STANDARD db01.db/t_foo/metadata/snap-125388589100921283-1-3485210c-2c99-4c72-bb36-030c8e0a4a90.avro

If you have DuckDB available locally you can run:

$ docker compose exec mc bash -c \
        "mc cat minio/warehouse/db_rmoff.db/t_foo/data/00000-0-41e6f635-3859-46ef-a57e-de5f774203fa-00001.parquet" \
        > /tmp/data.parquet && \
        duckdb :memory: "SELECT * FROM read_parquet('/tmp/data.parquet')"
┌─────────┬───────┐
│   c1    │  c2   │
│ varchar │ int32 │
├─────────┼───────┤
│ a       │    42 │
└─────────┴───────┘

(replace 00000-0-41e6f635-3859-46ef-a57e-de5f774203fa-00001.parquet with the actual filename)

Metastore

Copy the DerbyDB and launch ij:

docker compose exec -it hive-metastore bash -c "cp -r /tmp/metastore_db/ /tmp/metastore_db2 && rlwrap ./db-derby-10.14.2.0-bin/bin/ij"

Connect to the copy of the DB:

connect 'jdbc:derby:/tmp/metastore_db2/';

Query it

ij> select * from dbs;
DB_ID  |DESC                   |DB_LOCATION_URI           |NAME        |OWNER_NAME |OWNER_TYPE|CTLG_NAME
--------------------------------------------------------------------------------------------------------
1      |Default Hive database  |file:/user/hive/warehouse |default     |public     |ROLE      |hive
2      |NULL                   |s3a://warehouse/db01.db   |db01        |root       |USER      |hive


2 rows selected
ij>

ij> SELECT DB."NAME",
	       DB.DB_LOCATION_URI,
	       TB.TBL_NAME,
	       TBP.PARAM_VALUE
	FROM   APP.DBS DB
	       INNER JOIN APP.TBLS TB
	               ON DB.DB_ID = TB.DB_ID
	       INNER JOIN APP.TABLE_PARAMS TBP
	               ON TB.TBL_ID = TBP.TBL_ID
	WHERE  TBP.PARAM_KEY = 'metadata_location';

NAME    |DB_LOCATION_URI            |TBL_NAME|PARAM_VALUE                                                                                         |
--------+---------------------------+--------+----------------------------------------------------------------------------------------------------+
db_rmoff|s3a://warehouse/db_rmoff.db|t_foo   |s3a://warehouse/t_foo/metadata/00000-5946940a-04fa-4a60-9bc9-b83db818560a.metadata.json             |