📅 最后修改于: 2020-11-27 05:03:52 🧑 作者: Mango
本章介绍了HSQLDB的不同数据类型。 HSQLDB服务器提供六类数据类型。
确切的数值数据类型
| Data Type |
From |
To |
| bigint |
-9,223,372,036,854,775,808 |
9,223,372,036,854,775,807 |
| int |
-2,147,483,648 |
2,147,483,647 |
| smallint |
-32,768 |
32,767 |
| tinyint |
0 |
255 |
| bit |
0 |
1 |
| decimal |
-10^38 +1 |
10^38 -1 |
| numeric |
-10^38 +1 |
10^38 -1 |
| money |
-922,337,203,685,477.5808 |
+922,337,203,685,477.5807 |
| smallmoney |
-214,748.3648 |
+214,748.3647 |
近似数值数据类型
| Data Type |
From |
To |
| float |
-1.79E + 308 |
1.79E + 308 |
| real |
-3.40E + 38 |
3.40E + 38 |
日期和时间数据类型
| Data Type |
From |
To |
| datetime |
Jan 1, 1753 |
Dec 31, 9999 |
| smalldatetime |
Jan 1, 1900 |
Jun 6, 2079 |
| date |
Stores a date like June 30, 1991 |
| time |
Stores a time of day like 12:30 P.M. |
注意-这里的datetime精度为3.33毫秒，而较小的datetime精度为1分钟。
字符的数据类型
| Data Type |
Description |
| char |
Maximum length of 8,000 characters (Fixed length non-Unicode characters) |
| varchar |
Maximum of 8,000 characters (Variable-length non-Unicode data) |
| varchar(max) |
Maximum length of 231 characters, variable-length non-Unicode data (SQL Server 2005 only) |
| text |
Variable-length non-Unicode data with a maximum length of 2,147,483,647 characters |
Unicode字符字符串数据类型
| Data Type |
Description |
| nchar |
Maximum length of 4,000 characters (Fixed length Unicode) |
| nvarchar |
Maximum length of 4,000 characters (Variable length Unicode) |
| nvarchar(max) |
Maximum length of 231 characters (SQL Server 2005 only),(Variable length Unicode) |
| ntext |
Maximum length of 1,073,741,823 characters (Variable length Unicode) |
二进制数据类型
| Data Type |
Description |
| binary |
Maximum length of 8,000 bytes (Fixed length binary data) |
| varbinary |
Maximum length of 8,000 bytes (Variable length binary data) |
| varbinary(max) |
Maximum length of 231 bytes (SQL Server 2005 only), (Variable length Binary data) |
| image |
Maximum length of 2,147,483,647 bytes (Variable length Binary Data) |
杂项数据类型
| Data Type |
Description |
| sql_variant |
Stores values of various SQL Server-supported data types, except text, ntext, and timestamp |
| timestamp |
Stores a database-wide unique number that gets updated every time a row gets updated |
| uniqueidentifier |
Stores a globally unique identifier (GUID) |
| xml |
Stores XML data. You can store xml instances in a column or a variable (SQL Server 2005 only) |
| cursor |
Reference to a cursor object |
| table |
Stores a result set for later processing |