SQL Write #
Syntax #
INSERT { INTO | OVERWRITE } table_identifier [ part_spec ] [ column_list ] { value_expr | query };
For more information, please check the syntax document:
INSERT INTO #
Use INSERT INTO
to apply records and changes to tables.
INSERT INTO my_table SELECT ...
INSERT INTO
supports both batch and streaming mode. In Streaming mode, by default, it will also perform compaction,
snapshot expiration, and even partition expiration in Flink Sink (if it is configured).
For multiple jobs to write the same table, you can refer to dedicated compaction job for more info.
Overwriting the Whole Table #
For unpartitioned tables, Paimon supports overwriting the whole table.
(or for partitioned table which disables dynamic-partition-overwrite
option).
Use INSERT OVERWRITE
to overwrite the whole unpartitioned table.
INSERT OVERWRITE my_table SELECT ...
Overwriting a Partition #
For partitioned tables, Paimon supports overwriting a partition.
Use INSERT OVERWRITE
to overwrite a partition.
INSERT OVERWRITE my_table PARTITION (key1 = value1, key2 = value2, ...) SELECT ...
Dynamic Overwrite #
Flink’s default overwrite mode is dynamic partition overwrite (that means Paimon only deletes the partitions
appear in the overwritten data). You can configure dynamic-partition-overwrite
to change it to static overwritten.
-- MyTable is a Partitioned Table
-- Dynamic overwrite
INSERT OVERWRITE my_table SELECT ...
-- Static overwrite (Overwrite whole table)
INSERT OVERWRITE my_table /*+ OPTIONS('dynamic-partition-overwrite' = 'false') */ SELECT ...
Truncate tables #
You can use INSERT OVERWRITE
to purge tables by inserting empty value.
INSERT OVERWRITE my_table /*+ OPTIONS('dynamic-partition-overwrite'='false') */ SELECT * FROM my_table WHERE false;
TRUNCATE TABLE my_table;
Purging Partitions #
Currently, Paimon supports two ways to purge partitions.
-
Like purging tables, you can use
INSERT OVERWRITE
to purge data of partitions by inserting empty value to them. -
Method #1 does not support to drop multiple partitions. In case that you need to drop multiple partitions, you can submit the drop_partition job through
flink run
.
-- Syntax
INSERT OVERWRITE my_table /*+ OPTIONS('dynamic-partition-overwrite'='false') */
PARTITION (key1 = value1, key2 = value2, ...) SELECT selectSpec FROM my_table WHERE false;
-- The following SQL is an example:
-- table definition
CREATE TABLE my_table (
k0 INT,
k1 INT,
v STRING
) PARTITIONED BY (k0, k1);
-- you can use
INSERT OVERWRITE my_table /*+ OPTIONS('dynamic-partition-overwrite'='false') */
PARTITION (k0 = 0) SELECT k1, v FROM my_table WHERE false;
-- or
INSERT OVERWRITE my_table /*+ OPTIONS('dynamic-partition-overwrite'='false') */
PARTITION (k0 = 0, k1 = 0) SELECT v FROM my_table WHERE false;
Updating tables #
Important table properties setting:
- Only primary key table supports this feature.
- MergeEngine needs to be deduplicate or partial-update to support this feature.
- Do not support updating primary keys.
Currently, Paimon supports updating records by using UPDATE
in Flink 1.17 and later versions. You can perform UPDATE
in Flink’s batch
mode.
-- Syntax
UPDATE table_identifier SET column1 = value1, column2 = value2, ... WHERE condition;
-- The following SQL is an example:
-- table definition
CREATE TABLE my_table (
a STRING,
b INT,
c INT,
PRIMARY KEY (a) NOT ENFORCED
) WITH (
'merge-engine' = 'deduplicate'
);
-- you can use
UPDATE my_table SET b = 1, c = 2 WHERE a = 'myTable';
Deleting from table #
Important table properties setting:
- Only primary key tables support this feature.
- If the table has primary keys, MergeEngine needs to be deduplicate to support this feature.
- Do not support deleting from table in streaming mode.
-- Syntax
DELETE FROM table_identifier WHERE conditions;
-- The following SQL is an example:
-- table definition
CREATE TABLE my_table (
id BIGINT NOT NULL,
currency STRING,
rate BIGINT,
dt String,
PRIMARY KEY (id, dt) NOT ENFORCED
) PARTITIONED BY (dt) WITH (
'merge-engine' = 'deduplicate'
);
-- you can use
DELETE FROM my_table WHERE currency = 'UNKNOWN';