GaussDB(DWS) Link Parameters

Table 1 describes the DWS link parameters.

Do not change the password or user when the job is running. If you do so, the password will not take effect immediately and the job will fail.

**Table 1** DWS link parameters
Parameter	Description	Example Value
Name	Link name, which should be defined based on the data source type, so it is easier to remember what the link is for	dws_link
Database Server	IP address or domain name of the database to connect Click Select next to the text box to obtain the list of instances.	192.168.0.1
Port	Port of the database to connect	The port number varies depending on the database.
Database Name	Name of the database to connect	dbname
Username	Username used for accessing the database. This user must have the permissions to read and write data tables and metadata.	cdm
Password	Password of the user	-
Use Agent	The agent function will be unavailable soon and does not need to be configured.	-
Agent	The agent function will be unavailable soon and does not need to be configured.	-
Reference Sign	(Optional) Delimiter between the names of the referenced tables or columns. For details, see the product documentation of the corresponding database.	"
Fetch Size	(Optional) Displayed when you click Show Advanced Attributes. Number of rows obtained by each request. Set this parameter based on the data source and the job's data size. If the value is either too large or too small, the job may run for a long time.	1000
SSL Encryption	(Optional) If you set this parameter to Yes, CDM can connect to the database (on-premises databases excluded) in SSL encryption mode.	Yes NOTE: To enable SSL encryption, you must ensure that it is enabled for GaussDB(DWS).
Link Attributes	(Optional) Click Add to add the JDBC connector attributes of multiple specified data sources. For details, see the JDBC connector document of the corresponding database. The following are some examples: connectTimeout=60 and socketTimeout=300: When a large amount of data needs to be migrated or the entire table is retrieved using query statements, the migration fails due to connection timeout. In this case, you can customize the connection timeout interval (s) and socket timeout interval (s) to prevent failures caused by timeout. useCursorFetch=false: By default, useCursorFetch is enabled, indicating that the JDBC connector communicates with relational databases using a binary protocol. Some third-party systems may have compatibility issues, causing migration time conversion errors. In this case, you can disable this function. Open-source MySQL databases support the useCursorFetch parameter, and you do not need to set this parameter.	sslmode=require NOTE: If SSL encryption is enabled but sslmode is not set, the link may fail.