Apache Derby 简明教程
Apache Derby - Data Types
数据类型是一种属性，用于指定任何对象的数据类型。每个列、变量和表达式都具有相关的类型。您可以在创建表时使用这些数据类型。您可以根据自己的要求为表列选择数据类型。
Data Type is an attribute that specifies the type of data of any object. Each column, variable and expression has a related data type. You can use these data types while creating your tables. You can choose a data type for a table column based on your requirement.
Derby 服务器提供以下列出的类别的多种数据类型供您使用 −
Derby Server offers several categories of data types for your use as listed below −
Integer Numeric Data Types
以下是整数数值数据类型的列表 −
Following is the list of integer numeric data types −
DATA TYPE |
SIZE |
FROM |
TO |
SMALLINT |
2 bytes |
-32768 |
32767 |
INTEGER |
4 bytes |
-2,147,483,648 |
2,147,483,647 |
BIGINT |
8 bytes |
-9223372036854775808 |
9223372036854775808 |