DataWorks:ClickHouse data source

Configure a single-table offline sync task

• For more information about the procedure, see Configure a task in the codeless UI and Configure a task in the code editor.

• For more information about all parameters and script examples in code editor mode, see Appendix: Script demo and parameter descriptions.

Configure full-database offline read sync

For more information about the procedure, see Configure a real-time full database synchronization task.

Configure a batch synchronization task by using the code editor

If you want to configure a batch synchronization task by using the code editor, you must configure the related parameters in the script based on the unified script format requirements. For more information, see Configure a task in the code editor. The following information describes the parameters that you must configure for data sources when you configure a batch synchronization task by using the code editor.

Reader script demo

{
    "type": "job",
    "version": "2.0",
    "steps": [
        {
            "stepType": "clickhouse", // Plug-in name.
            "parameter": {
                "fetchSize":1024,// Number of records fetched per batch from the database server.
                "datasource": "example",
                "column": [   // Column names.
                    "id",
                    "name"
                ],
                "where": "",    // Filter condition.
                "splitPk": "",  // Shard key.
                "table": ""    // Table name.
            },
            "name": "Reader",
            "category": "reader"
        },
        {
            "stepType": "clickhouse",
            "parameter": {
                "postSql": [
                    "update @table set db_modify_time = now() where db_id = 1"
                ],
                "datasource": "example",    // Data source.
                "batchByteSize": "67108864",
                "column": [
                    "id",
                    "name"
                ],
                "writeMode": "insert",
                "encoding": "UTF-8",
                "batchSize": 1024,
                "table": "ClickHouse_table",
                "preSql": [
                    "delete from @table where db_id = -1"
                ]
            },
            "name": "Writer",
            "category": "writer"
        }
    ],
    "setting": {
        "executeMode": null,
        "errorLimit": {
            "record": "0"  // Maximum number of error records allowed during sync.
        },
        "speed": {
         "throttle":true,// When throttle is false, mbps is ignored (no throttling). When throttle is true, throttling is enabled.
            "concurrent":1 // Job concurrency.
            "mbps":"12",// Throttling rate. 1 mbps = 1 MB/s.
        }
    },
    "order": {
        "hops": [
            {
                "from": "Reader",
                "to": "Writer"
            }
        ]
    }
}

Reader script parameters

Writer script demo

{
    "type":"job",
    "version":"2.0",// Version number.
    "steps":[
        {
            "stepType":"stream",
            "parameter":{},
            "name":"Reader",
            "category":"reader"
        },
        {
            "stepType":"clickhouse",// Plug-in name.
            "parameter":{
                "username": "",
                "password": "",
                "column": [// Fields.
                    "id",
                    "name"
                ],
                "connection": [
                    {
                        "table": [// Table name.
                            "ClickHouse_table"
                        ],
                        "jdbcUrl": "jdbc:clickhouse://ip:port/database"
                    }
                ],
                "preSql": [ // SQL statement executed before the sync task runs.
                    "TRUNCATETABLEIFEXISTStablename"
                ],
                "postSql": [// SQL statement executed after the sync task runs.
                    "ALTERTABLEtablenameUPDATEcol1=1WHEREcol2=2"
                ],
                "batchSize": "1024",
                "batchByteSize": "67108864",
                "writeMode": "insert"
            },
            "name":"Writer",
            "category":"writer"
        }
    ],
    "setting":{
        "errorLimit":{
            "record":"0"// Number of error records.
        },
        "speed":{
            "throttle":true,// When throttle is false, mbps is ignored (no throttling). When throttle is true, throttling is enabled.
            "concurrent":1, // Job concurrency.
            "mbps":"12"// Throttling rate. 1 mbps = 1 MB/s.
        }
    },
    "order":{
        "hops":[
            {
                "from":"Reader",
                "to":"Writer"
            }
        ]
    }
}

Writer script parameters