2006年7月21日星期五

Hibernate 字符类型映射 (Hibernate character/String mapping types)

Oralce 数据库映射注意事项:

1. 如果数据库中的类型为 char(1), 则映射为 character 或 char

// SQL
PUBLISHED char(1)

// POJO java
char published;

// mapping
<property name="published" type="character">
<column name="PUBLISHED" length="1" />
</property>


若映射成了 string 的话,在数据类型校验时会出错:


// POJO java
String published;

// mapping

<property name="published" type="string">
<column name="PUBLISHED" length="1" />
</property>

类似的错误输出为:
Wrong column type: PUBLISHED, expected: varchar2(1 char)
at org.hibernate.mapping.Table.validateColumns(Table.java:261)




2. 如果为 varchar2(1), 则映射为 string

// SQL
INCLUDES_SS_LIB varchar2(1)

// POJO java
String includedSsLib;

// mapping
<property name="includesSsLib" type="string">
<column name="INCLUDES_SS_LIB" length="1" />
</property>


若映射成了 character 的话,在数据类型校验时会出错:

// POJO java
char includedSsLib;

// mapping

<property name="includesSsLib" type="character">
<column name="INCLUDES_SS_LIB" length="1" />
</property>

类似的错误输出为:

Wrong column type: CHECKED, expected: char(1 char)
at org.hibernate.mapping.Table.validateColumns(Table.java:261)

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