Preparing for the Source Oracle Database

Before the synchronization, prepare some data types in the source database for verification after the synchronization is complete.

The following table lists data types supported by DRS.

**Table 1** Data type mapping
Data Type (Oracle)	Condition	Data Type (DDM)	Whether to Support Mapping
CHAR(n)	n ≤ 255	CHAR(n)	Yes
CHAR(n)	n > 255	VARCHAR(n)	Yes
VARCHAR(Size)	Length (row size) ≤ 65535	VARCHAR(n)	Yes
VARCHAR(Size)	Length (row size) > 65535	TEXT	Yes
VARCHAR2(n)	-	VARCHAR(n)	Yes
NCHAR(n)	n ≤ 255	NCHAR(n)	Yes
NCHAR(n)	n > 255	NVARCHAR(n)	Yes
NVARCHAR2(n)	-	NVARCHAR(n)	Yes
NUMBER(p,s)	s > 0	NUMBER(p,s)	Yes
NUMBER(p,s)	s ≤ 0	NUMBER(p-s,0)	Yes
BINARY_FLOAT	-	FLOAT	Yes
BINARY_DOUBLE	-	DOUBLE	Yes
FLOAT(b)	b ≤ 99	DECIMAL(b0.301032,b*0.30103)	Yes
FLOAT(b)	b > 99	DOUBLE	Yes
DATE	-	DATETIME	Yes
TIMESTAMP	-	TIMESTAMP	Yes
TIMESTAMP WITH LOCAL TIME ZONE	-	TIMESTAMP	Yes
TIMESTAMP WITH TIME ZONE	-	TIMESTAMP	Yes
INTERVAL	Incremental	VARCHAR(30)	No
INTERVAL	Full; 6 digit precision	VARCHAR(30)	Yes
BLOB	-	LONGBLOB	Yes
CLOB	-	LONGTEXT	Yes
NCLOB	-	LONGTEXT	Yes
LONG	-	LONGTEXT	Yes
LONG_RAW	-	LONGBLOB	Yes
RAW	-	VARBINARY	Yes
ROWID	-	VARCHAR(18)	Yes

Perform the following steps to generate data in the source database:

Use a database connection tool to connect to the source Oracle database based on its IP address.
Construct data in the source database based on its supported data types.
1. Create a test user.
```
create user test_info identified by xxx;
```
  test_info indicates the user created for the test, and xxx indicates the password of the user.
2. Assign permissions to the user.
```
grant dba to test_info;
```
3. Create a data table under the user.
```
CREATE TABLE test_info.table3(
ID INT,
COL01 CHAR(100),
COL02 NCHAR(100),
PRIMARY KEY(ID)
);
```
4. Insert two rows of data.
  insert into test_info.table3 values(4,'huawei','xian');
  
  insert into test_info.table3 values(2,'DRS-test','test1');
  
  insert into test_info.table3 values(1,'huawei','xian');
5. Make the above statements take effect.
  commit;