数据类型说明
外部类型所包含的所有数据如下：
当前不支持的内部类型有XML，JSON，几何类型，数据库对象tablespace。
| External Data Type | Code | Program Variable(1) | 是否支持 |
|---|---|---|---|
| VARCHAR2 | 1 | char[n] | 是 |
| NUMBER | 2 | unsigned char[21] | 否 |
| 8-bit signed | 3 | signed char | 是 |
| 16-bit signed | 3 | signed short, signed int | 是 |
| 32-bit signed | 3 | signed int, signed long | 是 |
| 64-bit signed | 3 | signed long, signed long long | 是 |
| FLOAT | 4 | float, double | 是 |
| NULL-terminated STRING | 5 | char[n+1] | 是 |
| VARNUM | 6 | char[22] | 是 |
| LONG | 8 | char[n] | 是 |
| VARCHAR | 9 | char[n+sizeof(short integer)] | 是 |
| DATE | 12 | char[7] | 是 |
| VARRAW | 15 | unsigned char[n+sizeof(short integer)] | 否 |
| native float | 21 | float | 是 |
| native double | 22 | double | 是 |
| RAW | 23 | unsigned char[n] | 否 |
| LONG RAW | 24 | unsigned char[n] | 否 |
| UNSIGNED INT | 68 | unsigned | 否 |
| LONG VARCHAR | 94 | char[n+sizeof(integer)] | 是 |
| LONG VARRAW | 95 | unsigned char[n+sizeof(integer)] | 否 |
| CHAR | 96 | char[n] | 是 |
| CHARZ | 97 | char[n+1] | 是 |
| ROWID | 104 | OCIRowid * | 否 |
| NAMED DATATYPE | 108 | struct | 否 |
| REF | 110 | OCIRef | 否 |
| Character LOB descriptor | 112 | OCILobLocator | 否 |
| Binary LOB descriptor | 113 | OCILobLocator | 否 |
| Binary FILE descriptor | 114 | OCILobLocator | 否 |
| JSON descriptor | 119 | OCIJson | 否 |
| OCI STRING | 155 | OCIString | 否 |
| OCI DATE | 156 | OCIDate * | 否 |
| ANSI DATE | 184 | OCIDateTime * | 否 |
| TIMESTAMP | 187 | OCIDateTime * | 否 |
| TIMESTAMP WITH TIME ZONE | 188 | OCIDateTime * | 否 |
| INTERVAL YEAR TO MONTH | 189 | OCIInterval * | 否 |
| INTERVAL DAY TO SECOND | 190 | OCIInterval * | 否 |
| TIMESTAMP WITH LOCAL TIME ZONE | 232 | OCIDateTime * | 否 |
