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    MaxCompute:CDC (Invitational Preview)

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    MaxCompute:CDC (Invitational Preview)

    Last Updated:Mar 25, 2026

    Change Data Capture (CDC) records row-level inserts, updates, and deletes on Delta tables as an incremental event stream. Downstream systems can consume this stream for incremental computing, data synchronization, stream processing, and auditing — without scanning the full table on each run.

    CDC is currently in invitational preview. For usage instructions, see Incremental calculation overview.

    Use cases

    • Incremental computing: Consume change records to update materialized views without reprocessing the full table.

    • Stream processing: Feed CDC records into Flink jobs or other stream processors.

    • Multi-engine data synchronization: Propagate incremental changes across different compute engines.

    • Log auditing: Retain a complete record of all row-level operations for compliance and governance.

    Choose a CDC mode

    CDC supports two modes. Choose based on whether your workload requires real-time writes via Tunnel.

    Synchronous CDCAsynchronous CDC
    SQL DML operationsSupportedSupported
    Real-time writes via TunnelNot supportedSupported
    CDC data availabilityImmediately after the SQL operation completesAsynchronously, after the configured interval

    Enable CDC on a Delta table

    Synchronous CDC

    Add "acid.cdc.mode.enable"="true" when creating a Delta table.

    CREATE TABLE acid_with_cdc_tbl (pk BIGINT NOT NULL PRIMARY KEY, val BIGINT)
tblproperties ("transactional" = "true", "acid.cdc.mode.enable"="true");

    Optional properties:

    PropertyDescriptionDefault
    "cdc.insert.into.passthrough.enable"="true"Allows INSERT INTO statements on CDC-enabled tables. Written data appears as INSERT type only. Primary keys must be unique — rows with duplicate PKs cause query failures.Disabled
    "cdc.data.retain.hours"="24"Retention period for CDC data, in hours. Range: 1–168.24

    Asynchronous CDC

    Add "acid.cdc.mode.enable"="true", "acid.cdc.build.async"="true", and "acid.cdc.build.interval" when creating a Delta table.

    CREATE TABLE acid_with_cdc_build_tbl (pk BIGINT NOT NULL PRIMARY KEY, val BIGINT)
tblproperties ("transactional" = "true",
               "acid.cdc.mode.enable"="true",
               "acid.cdc.build.async"="true",
               "acid.cdc.build.interval"="300");

    Properties:

    PropertyRequiredDescriptionRange
    "acid.cdc.mode.enable"="true"YesEnables CDC for the Delta table.—
    "acid.cdc.build.async"="true"YesEnables asynchronous CDC building. Supports real-time writes via Tunnel. CDC data for SQL DML operations is also generated asynchronously.—
    "acid.cdc.build.interval"="300"YesInterval for asynchronous CDC building, in seconds.60–3540
    "odps.storage.orc.enable.memcmp.sort.key"="true"NoProject-level or session-level property that improves asynchronous CDC build and query performance.—

    Query CDC data

    Use the table_changes function to query CDC change records by version or timestamp range.

    Syntax

    SELECT * FROM table_changes('<table_name>', <start> [, <end>]);

    Parameters

    ParameterRequiredTypeDescription
    table_nameYes—The Delta table to query.
    startYesBIGINT or STRINGStarting version for the CDC data query. Find version numbers with SHOW HISTORY FOR TABLE <table_name>. For STRING, use yyyy-mm-dd hh:mi:ss.
    endNoBIGINT or STRINGEnding version for the CDC data query. Defaults to the latest version if omitted. For STRING, use yyyy-mm-dd hh:mi:ss.

    Return columns

    In addition to the table's data columns, table_changes returns three system columns:

    ColumnDescription
    __meta_timestampSystem time when the row was written.
    __meta_op_typeOperation type: 1 = INSERT, 0 = DELETE.
    __meta_is_updateWhether the row is part of an UPDATE: 1 = yes, 0 = no.

    Combine __meta_op_type and __meta_is_update to identify the full operation:

    __meta_op_type__meta_is_updateOperation
    10New row from an INSERT
    11Post-update value (the new value after UPDATE)
    01Pre-update value (the original value before UPDATE)
    00Deleted row

    Example

    Step 1: Create a CDC-enabled table.

    CREATE TABLE acid_cdc_table(id1 STRING NOT NULL, id2 STRING NOT NULL, key1 BIGINT, key2 BIGINT, PRIMARY KEY(id1, id2))
tblproperties("transactional" = "true", "acid.cdc.mode.enable"="true");

    Step 2: Insert data.

    -- Data insertion time 2025-04-07 11:56:57
INSERT INTO acid_cdc_table VALUES ('1', '1006', 1006, 1006);
-- Data insertion time 2025-04-07 12:15:00
INSERT INTO acid_cdc_table VALUES ('1', '1008', 1008, 1008);
-- Data insertion time 2025-04-07 13:24:00
INSERT INTO acid_cdc_table VALUES ('1', '1032', 1032, 1032);
-- Data insertion time 2025-04-07 14:00:00
INSERT INTO acid_cdc_table VALUES ('1', '1045', 1045, 1045);
-- Data insertion time 2025-04-07 14:47:00
INSERT INTO acid_cdc_table VALUES ('1', '1045', 1045, 1045);

    Step 3: Find table versions.

    SHOW HISTORY FOR TABLE acid_cdc_table;

    Output:

    ObjectType      ObjectId                                ObjectName              VERSION(LSN)            Time                    Operation
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000001        2025-04-07 11:55:59     CREATE
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000002        2025-04-07 11:56:57     APPEND
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000003        2025-04-07 12:00:13     MINOR_COMPACT
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000004        2025-04-07 12:15:32     APPEND
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000005        2025-04-07 12:30:02     MINOR_COMPACT
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000006        2025-04-07 13:24:47     APPEND
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000007        2025-04-07 13:30:02     MINOR_COMPACT
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000008        2025-04-07 14:00:41     APPEND
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000009        2025-04-07 14:15:15     MINOR_COMPACT
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000010        2025-04-07 14:47:46     APPEND
TABLE           a4a78d3f6af04d85a57a90deff884021        acid_cdc_table          0000000000000011        2025-04-07 15:00:11     MINOR_COMPACT

    Step 4: Query CDC records.

    Query all changes after 2025-04-07 12:00:00 (equivalent to version 3):

    SELECT * FROM table_changes('acid_cdc_table', '2025-04-07 12:00:00');
-- Equivalent to
SELECT * FROM table_changes('acid_cdc_table', 3);

    Output:

    +------------+------------+------------+------------+------------------+----------------+------------------+
| id1        | id2        | key1       | key2       | __meta_timestamp | __meta_op_type | __meta_is_update |
+------------+------------+------------+------------+------------------+----------------+------------------+
| 1          | 1045       | 1045       | 1045       | 2025-04-07 14:00:34 | 1           | 0                |
| 1          | 1008       | 1008       | 1008       | 2025-04-07 12:15:28 | 1           | 0                |
| 1          | 1032       | 1032       | 1032       | 2025-04-07 13:24:43 | 1           | 0                |
| 2          | 1045       | 1045       | 1045       | 2025-04-07 14:47:41 | 1           | 0                |
+------------+------------+------------+------------+------------------+----------------+------------------+

    Query changes within a specific range (2025-04-07 12:00:00 to 13:30:00, equivalent to versions 3–6):

    SELECT * FROM table_changes('acid_cdc_table', '2025-04-07 12:00:00', '2025-04-07 13:30:00');
-- Equivalent to
SELECT * FROM table_changes('acid_cdc_table', 3, 6);

    Output:

    +------------+------------+------------+------------+------------------+----------------+------------------+
| id1        | id2        | key1       | key2       | __meta_timestamp | __meta_op_type | __meta_is_update |
+------------+------------+------------+------------+------------------+----------------+------------------+
| 1          | 1008       | 1008       | 1008       | 2025-04-07 12:15:28 | 1           | 0                |
| 1          | 1032       | 1032       | 1032       | 2025-04-07 13:24:43 | 1           | 0                |
+------------+------------+------------+------------+------------------+----------------+------------------+

    Consume CDC data with a Stream

    A Stream object tracks a read offset into a Delta table's CDC history. Create a Stream with "read_mode"="cdc" to consume CDC data incrementally.

    For full Stream documentation, see Stream object.

    Syntax

    CREATE STREAM [IF NOT EXISTS] <stream_name>
ON TABLE <delta_table_name> VERSION AS OF <v>
strmproperties ("read_mode"="cdc")

    The "read_mode"="cdc" property sets the Stream to consume CDC data based on the query version range.

    Example

    -- Create the source table with CDC enabled.
CREATE TABLE acid_with_cdc_stream (id1 BIGINT NOT NULL PRIMARY KEY, id2 BIGINT)
tblproperties ("transactional" = "true", "acid.cdc.mode.enable"="true","cdc.insert.into.passthrough.enable"="true");

-- Insert data.
INSERT INTO acid_with_cdc_stream VALUES (1, 1006), (2, 1008), (3, 1032);

-- Create a Stream starting at version 1.
CREATE STREAM delta_table_stream ON TABLE acid_with_cdc_stream VERSION AS OF 1 strmproperties ("read_mode"="cdc");

-- Inspect the Stream.
DESC STREAM delta_table_stream;

    Output:

    Name                                    delta_table_stream
Project                                 yunqi_y****
Schema                                  default
Create Time                             2024-12-03 11:13:12
Last Modified Time                      2024-12-03 11:13:12
Offset Version                          1
Reference Table Project                 yunqi_y****
Reference Table Schema                  default
Reference Table Name                    acid_with_cdc_stream
Reference Table Id                      b89ec113f50944d5b8e52ce6a00c****
Reference Table Version                 2
Parameters                              {"read_mode": "cdc"}

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