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JDOQL子查询计数问题

jdoql jdo

1

Timo Westkämper · 技术社区 · 15 年前

我对JDOQL(使用DataNucleus)的子查询计数有问题。以下查询

SELECT this.price
FROM com.mysema.query.jdo.test.domain.Product
WHERE (SELECT count(other)
FROM com.mysema.query.jdo.test.domain.Product other
WHERE other.price > this.price) > a1
PARAMETERS java.lang.Long a1

导致异常

javax.jdo.JDOUserException: Cannot perform operation ">" on SubqueryExpression "(SELECT COUNT("OTHER".PRODUCT_ID) FROM PRODUCT "OTHER" WHERE "OTHER".PRICE > THIS.PRICE)" and IntegerLiteral "?"
    at org.datanucleus.jdo.NucleusJDOHelper.getJDOExceptionForNucleusException(NucleusJDOHelper.java:390)
    at org.datanucleus.jdo.JDOQuery.executeWithArray(JDOQuery.java:321)

以下查询都不起作用:

SELECT this.price
FROM com.mysema.query.jdo.test.domain.Product
WHERE !(SELECT other
FROM com.mysema.query.jdo.test.domain.Product other
WHERE other.price > this.price).isEmpty()

1 回复 | 直到 15 年前

1

Timo Westkämper 15 年前

我通过从DataNucleus 2.0.4升级到2.1.2解决了问题。第一个查询有效。