Overview of Data Migration Scenarios

To centrally analyze and manage scattered data from various systems, you can utilize migration tools like Cloud Data Migration (CDM) to migrate the data to DLI. Once the migration is complete, you can submit DLI jobs to analyze the data.

CDM supports multiple types of data sources, such as databases, data warehouses, and files. You can configure data source migration tasks on the GUI to enhance the efficiency of data migration and integration.

Figure 1 Migrating data to DLI

Common Migration Scenarios and Solutions

**Table 1** Common migration scenarios and solutions
Data Type	Migration Tool	Solution
Hive	CDM	Migrating Data from Hive to DLI
Kafka	CDM	Migrating Data from MRS Kafka to DLI
Elasticsearch	CDM	Migrating Data from Elasticsearch to DLI
RDS	CDM	Migrating Data from RDS to DLI
GaussDB(DWS)	CDM	Migrating Data from GaussDB(DWS) to DLI

Data Type Mapping

Refer to Table 2 for data type mapping between data sources and destinations during data migration between DLI and other cloud services and platforms. This will aid in data type conversion and mapping.

**Table 2** Data type mapping
MySQL	Hive	GaussDB(DWS)	Oracle	PostgreSQL	Hologres	DLI Spark
CHAR	CHAR	CHAR	CHAR	CHAR	CHAR	CHAR
VARCHAR	VARCHAR	VARCHAR	VARCHAR	VARCHAR	VARCHAR	VARCHAR/STRING
DECIMAL	DECIMAL	NUMERIC	NUMERIC	NUMERIC	DECIMAL	DECIMAL
INT	INT	INTEGER	NUMBER	INTEGER	INTEGER	INT
BIGINT	BIGINT	BIGINT	NUMBER	BIGINT	BIGINT	BIGINT/LONG
TINYINT	TINYINT	SMALLINT	NUMBER	SMALLINT	SMALLINT	TINYINT
SMALLINT	SMALLINT	SMALLINT	NUMBER	SMALLINT	SMALLINT	SMALLINT/SHORT
BINARY	BINARY	BYTEA	RAW	BYTEA	BYTEA	BINARY
VARBINARY	BINARY	BYTEA	RAW	BYTEA	BYTEA	BINARY
FLOAT	FLOAT	FLOAT4	FLOAT	DOUBLE	FLOAT4	FLOAT
DOUBLE	DOUBLE	FLOAT8	FLOAT	REAL/DOUBLE	FLOAT8	DOUBLE
DATE	DATE	TIMESTAMP	DATE	DATE	DATE	DATE
TIME	Not supported (use String instead)	TIME	DATE	TIME	TIME	Not supported (use String instead)
DATETIME	TIMESTAMP	TIMESTAMP	TIME	TIME	TIMESTAMP	TIMESTAMP
TINYINT	TINYINT	BOOLEAN	Not supported	TINYINT	BOOLEAN	BOOLEAN
Not supported (use TEXT instead)	Not supported (use String instead)	Not supported (use TEXT instead)	Not supported (use VARCHAR instead)	Not supported (use TEXT instead)	Not supported (use TEXT instead)	ARRAY
Not supported (use TEXT instead)	Not supported (use String instead)	Not supported (use TEXT instead)	Not supported (use VARCHAR instead)	Not supported (use TEXT instead)	Not supported (use TEXT instead)	MAP
Not supported (use TEXT instead)	Not supported (use String instead)	Not supported (use TEXT instead)	Not supported (use VARCHAR instead)	Not supported (use TEXT instead)	Not supported (use TEXT instead)	STRUCT