| Oracle | MySQL | PostgreSQL | Java | |
| 数 | NUMBER | decimal | numeric | double BigDecimal |
| 整数 | int | integer | Integer | |
| smallint | smallint(int2) | Integer | ||
| tinyint | ||||
| bigint | bigint | |||
| 浮点数 | float | float | Float | |
| double | float8 | Double | ||
| 字符 | CHAR | char | char | String |
| VARCHAR2 | varchar | varchar | String | |
| 日期 | date | date | Date | |
| datetime | timestamp | Date |