Planning Data Export
For details about the data types that can be exported to MRS, see Table 1.
| Type | DWS Internal Table Type (Data Source Table) | DWS Write-Only Foreign Table Type | Hive Table Type |
|---|---|---|---|
| 1-byte integer | TINYINT | TINYINT (not recommended) | SMALLINT |
| SMALLINT (recommended) | SMALLINT | ||
| 2-byte integer | SMALLINT | SMALLINT | SMALLINT |
| 4-byte integer | INTEGER, BINARY_INTEGER | INTEGER | INT |
| 8-byte integer | BIGINT | BIGINT | BIGINT |
| Single-precision floating point number | FLOAT4, REAL | FLOAT4, REAL | FLOAT |
| Double-precision floating point number | DOUBLE PRECISION, FLOAT8, BINARY_DOUBLE | DOUBLE PRECISION, FLOAT8, BINARY_DOUBLE | DOUBLE |
| Scientific data type | DECIMAL, NUMERIC | DECIMAL[p (,s)] (The maximum precision can reach up to 38.) | precision ≤ 38: DECIMAL; precision > 38: STRING |
| Date type | DATE | TIMESTAMP[(p)] [WITHOUT TIME ZONE] | TIMESTAMP |
| Time type | TIME [(p)] [WITHOUT TIME ZONE], TIME [(p)] [WITH TIME ZONE] | TEXT | STRING |
| TIMESTAMP[(p)] [WITHOUT TIME ZONE], TIMESTAMP[(p)][WITH TIME ZONE], SMALLDATETIME | TIMESTAMP[(p)] [WITHOUT TIME ZONE] | TIMESTAMP | |
| INTERVAL DAY (l) TO SECOND (p), INTERVAL [FIELDS] [(p)] | VARCHAR(n) | VARCHAR(n) | |
| Boolean type | BOOLEAN | BOOLEAN | BOOLEAN |
| CHAR type | CHAR(n), CHARACTER(n), NCHAR(n) | CHAR(n), CHARACTER(n), NCHAR(n) | n ≤ 255: CHAR(n); n > 255: STRING |
| VARCHAR type | VARCHAR(n), CHARACTER VARYING(n), VARCHAR2(n) | VARCHAR(n) | n ≤ 65535: VARCHAR(n); n > 65535: STRING |
| NVARCHAR2(n) | TEXT | STRING | |
| String (large text object) | TEXT, CLOB | TEXT, CLOB | STRING |
| Binary type | BYTEA | BYTEA | BINARY |
| Monetary type | MONEY | NUMERIC | BIGINT |
For details about HDFS data export or MRS configuration, see the MapReduce Service User Guide.
