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    DataWorks:DM (Dameng)

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    DataWorks:DM (Dameng)

    Last Updated:Mar 26, 2026

    DataWorks Data Integration supports DM (Dameng) as both a source and a destination for offline batch synchronization. Use DM Reader to extract data from DM databases and DM Writer to load data into them.

    Capabilities

    Capability DM Reader DM Writer
    Offline (batch) sync Yes Yes
    Read from views Yes —
    Column pruning Yes —
    Column reordering Yes —
    Parallel read (splitPk) Yes (integer columns only) —
    Incremental sync (where) Yes —
    Pre SQL execution Yes Yes
    Post SQL execution — Yes
    Serverless resource groups Yes Yes
    Exclusive resource groups for Data Integration Yes Yes

    Supported field types

    DM Reader and DM Writer support most common relational database data types. The following table lists the DM data types that DM Reader can convert. Unsupported types cause a read error—verify your schema before configuring a sync task.

    Category DM data types
    Integer INT, TINYINT, SMALLINT, BIGINT
    Floating-point REAL, FLOAT, DOUBLE, NUMBER, DECIMAL
    String CHAR, VARCHAR, LONGVARCHAR, TEXT
    Date and time DATE, DATETIME, TIMESTAMP, TIME
    Boolean BIT
    Binary BINARY, VARBINARY, BLOB

    Configure a sync task

    Single-table offline sync

    Configure a task using either the codeless UI or the code editor:

    For the full script reference and parameter descriptions, see Script reference.

    Entire-database offline sync

    See Configure a real-time sync task for an entire database.

    Script reference

    When configuring a batch synchronization task in the code editor, use the unified script format. The following sections cover the DM-specific parameters for Reader and Writer.

    Reader

    Script example

    {
  "type": "job",
  "version": "2.0",
  "order": {
    "hops": [
      { "from": "Reader", "to": "Writer" }
    ]
  },
  "setting": {
    "errorLimit": { "record": "0" },
    "speed": {
      "throttle": true,
      "concurrent": 1,
      "mbps": "12"
    }
  },
  "steps": [
    {
      "category": "reader",
      "name": "Reader",
      "stepType": "dm",
      "parameter": {
        "datasource": "dm_datasource",
        "table": "table",
        "column": ["*"],
        "preSql": ["delete from XXX;"],
        "fetchSize": 2048
      }
    },
    {
      "category": "writer",
      "name": "Writer",
      "stepType": "stream",
      "parameter": {}
    }
  ]
}

    Reader parameters

    Parameter Required Default Description
    datasource Yes — Name of the DM data source. See Configure a DM data source.
    table Yes — Table to read data from.
    column Yes — Columns to sync, as a JSON array. Use ["*"] for all columns. Supports column pruning, column reordering, and constants (integer, string, null, function expression, floating-point, Boolean).
    splitPk No Empty Column used to split data for parallel reads. Set this to the primary key for even distribution and to avoid data hot spots. Only integer columns are supported—floating-point, string, date, and other types cause an error. If not set, the table is read with a single channel.
    where No — SQL filter condition appended to the query—for example, gmt_create>$bizdate for incremental sync, or limit 10 for testing. If not set, all rows are read.
    querySql No — Custom SQL query—for example, select a,b from table_a join table_b on table_a.id = table_b.id. When set, the column, table, and where parameters are ignored.
    fetchSize No 1,024 Number of rows fetched per batch. Higher values reduce network round-trips and improve throughput. Values above 2,048 may cause an out-of-memory (OOM) error.
    preSql No — SQL statement executed before the sync task starts. Only one statement is supported.

    Writer

    Script example

    {
  "type": "job",
  "version": "2.0",
  "order": {
    "hops": [
      { "from": "Reader", "to": "Writer" }
    ]
  },
  "setting": {
    "errorLimit": { "record": "" },
    "speed": {
      "throttle": true,
      "concurrent": 2,
      "mbps": "12"
    }
  },
  "steps": [
    {
      "category": "reader",
      "name": "Reader",
      "stepType": "oracle",
      "parameter": {
        "datasource": "aaa",
        "column": ["PROD_ID", "name"],
        "where": "",
        "splitPk": "",
        "encoding": "UTF-8",
        "table": "PENGXI.SALES"
      }
    },
    {
      "category": "writer",
      "name": "Writer",
      "stepType": "dm",
      "parameter": {
        "datasource": "dm_datasource",
        "table": "table",
        "column": ["id", "name"],
        "preSql": ["delete from XXX;"]
      }
    }
  ]
}

    Writer parameters

    Parameter Required Default Description
    datasource Yes — Name of the DM data source. See Configure a DM data source.
    table Yes — Destination table. If the table's schema differs from the username in the data source configuration, use the schema.table format.
    column Yes — Destination columns to write to, separated by commas. Do not use the default column settings.
    preSql No — SQL statement executed before the sync task starts—for example, to purge old data. Only one statement is supported; multiple statements disable transaction support.
    postSql No — SQL statement executed after the sync task completes—for example, to add a timestamp. Only one statement is supported; multiple statements disable transaction support.
    batchSize No 1,024 Number of rows written per batch. Higher values reduce network interactions and improve throughput. Values that are too large may cause an OOM error.

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