我正在尝试使用Grails 1.3.7和
MySQL 5.1.56为遗留数据库构建一组域类.我将BuildConfig.groovy文件中的MySQL连接器指定为’mysql:mysql-connector-java:5.1.13′.
数据库模式有一个名为’abstract’的TEXT类型的字段.
我在我的班级中声明相应的属性如下(为清楚起见,仅显示相关部分):
class Paper {
String abstractText
static mapping = {
table 'papers'
abstractText column: 'abstract'
}
static constraints = {
abstractText(nullable: false, maxSize: 65535)
}
}
当我运行集成测试时,我收到以下错误:
Wrong column type in citeseerx.papers for column abstract.
Found: text, expected: longtext
如果我改变声明
static mapping = {
abstractText column: 'abstract', type: 'text'
}
我犯了同样的错误.如果我将类型设置为’longtext’,我会得到
Could not determine type for: longtext, at table: papers,
for columns: [org.hibernate.mapping.Column(abstract)]
我看到了一个看似相关的Hibernate bug的讨论,我想知道是否有一个解决方法,或者其他一些方法来建模具有TEXT字段的模式.
谢谢,
基因
编辑:这是相关的DataSource.groovy片段:
dataSource {
pooled = true
driverClassName = "com.mysql.jdbc.Driver"
url = "jdbc:mysql://mydbhost:3306/mydb"
username = "u"
password = "p"
dbCreate = 'validate'
//dialect = org.hibernate.dialect.MySQL5Dialect
dialect = com.fxpal.citeseer.mysql.MyMySQLDialect
println("Setting dialog = ${dialect}")
}
hibernate {
cache.use_second_level_cache = true
cache.use_query_cache = true
cache.provider_class = 'net.sf.ehcache.hibernate.EhCacheProvider'
}
编辑(2):这是自定义方言类,正如@Stefan的答案所示:
import java.sql.Types;
/**
* An An extension to the SQL dialect for MySQL 5.1 to handle TEXT.
*
* @author Gene Golovchinsky
*/
public class MyMySQLDialect extends org.hibernate.dialect.MySQLDialect {
public MyMySQLDialect() {
super();
System.out.println("MyMySQLDialect: created new instance");
}
protected void registerVarcharTypes() {
System.out.println("MyMySQLDialect: RegisteringVarcharTypes");
registerColumnType( Types.VARCHAR, 16777215, "mediumtext" );
registerColumnType( Types.VARCHAR, 65535, "text" );
registerColumnType( Types.VARCHAR, 255, "varchar($l)" );
registerColumnType( Types.LONGVARCHAR, "longtext" );
}
}
最佳答案 您可以从
https://github.com/hibernate/hibernate-core/blob/master/hibernate-core/src/main/java/org/hibernate/dialect/MySQLDialect.java派生自定义方言并更改“文本”的映射.然后使用“dialect =”设置将新方言应用于Datasource.groovy.