Updated on 2024-08-30 GMT+08:00

From Hive

If the source link of a job is a Hive link, configure the source job parameters based on Table 1.

Table 1 Parameter description

Category

Parameter

Description

Example Value

Basic parameters

Database Name

Database name. Click the icon next to the text box. The dialog box for selecting the database is displayed.

default

Table Name

Hive table name. Click the icon next to the text box. The dialog box for selecting the table is displayed.

This parameter can be configured as a macro variable of date and time and a path name can contain multiple macro variables. When the macro variable of date and time works with a scheduled job, the incremental data can be synchronized periodically. For details, see Incremental Synchronization Using the Macro Variables of Date and Time.

NOTE:

If you have configured a macro variable of date and time and schedule a CDM job through DataArts Studio DataArts Factory, the system replaces the macro variable of date and time with (Planned start time of the data development jobOffset) rather than (Actual start time of the CDM jobOffset).

TBL_E

Read Mode

Two read modes are available: HDFS and JDBC. By default, the HDFS mode is used. If you do not need to use the WHERE condition to filter data or add new fields on the field mapping page, select the HDFS mode.

  • The HDFS mode shows good performance, but in this mode, you cannot use the WHERE condition to filter data or add new fields on the field mapping page.
  • The HDFS mode allows you to use the WHERE condition to filter data or add new fields on the field mapping page.

HDFS

Use SQL Statement

Whether you can use SQL statements to export data from a relational database

No

SQL Statement

When Use SQL Statement is set to Yes, enter an SQL statement here. CDM exports data based on the SQL statement.

NOTE:
  • SQL statements can only be used to query data. Join and nesting are supported, but multiple query statements are not allowed, for example, select * from table a; select * from table b.
  • With statements are not supported.
  • Comments, such as -- and /*, are not supported.
  • Addition, deletion, and modification operations are not supported, including but not limited to the following:
    • load data
    • delete from
    • alter table
    • create table
    • drop table
    • into outfile
  • If the SQL statement is too long, the request fails to be delivered. If you continue to create a job, the system displays an error message indicating that the request is incorrect. In this case, you need to simplify or clear the SQL statement and try again.

select id,name from sqoop.user;

Advanced attributes

Partition Values

This parameter is displayed when you select the HDFS read mode and click Show Advanced Attributes.

This parameter indicates extracting the partition of a specified value. The attribute name is the partition name. You can configure multiple values (separated by spaces) or a field value range. The time macro function is supported. For details, see Incremental Synchronization Using the Macro Variables of Date and Time.

NOTE:

If you have configured a macro variable of date and time and schedule a CDM job through DataArts Studio DataArts Factory, the system replaces the macro variable of date and time with (Planned start time of the data development jobOffset) rather than (Actual start time of the CDM jobOffset).

  • Attribute value in the single-value or multi-value filtering scenario:

    ${dateformat(yyyyMMdd, -1, DAY)} ${dateformat(yyyyMMdd)}

  • Attribute value in the range filtering scenario:

    ${value} >= ${dateformat(yyyyMMdd, -7, DAY)} && ${value} < ${dateformat(yyyyMMdd)}

WHERE Clause

This parameter is displayed when you select the JDBC read mode and click Show Advanced Attributes.

This parameter indicates the WHERE clause to be extracted. If this parameter is not set, the entire table is extracted. If the table to be migrated does not contain the fields specified by the WHERE clause, the migration will fail.

You can set a date macro variable to extract data generated on a specific date. For details, see Incremental Migration of Relational Databases.

NOTE:

If you have configured a macro variable of date and time and schedule a CDM job through DataArts Studio DataArts Factory, the system replaces the macro variable of date and time with (Planned start time of the data development jobOffset) rather than (Actual start time of the CDM jobOffset).

age > 18 and age <= 60

If the data source is Hive, CDM will automatically partition data using the Hive data partitioning file.