列名称错误无效

Question

我尝试按瞬态属性排序，但因SQL错误而失败：列名错误无效。

请在我的代码下面找到：

在声明的域类中：

static transients = ['sortCandidateLastName']

查询我要执行的内容：

当我尝试在Oracle中运行以下查询时：它运行正常

( select * from  (  select row_.*  ,rownum rownum_  from  (  select * from booking b where b.marked_deleted='N' order by  (select c.cand_id from candidate c where b.cand_id = c.cand_id) asc   ) row_ where rownum <= 15  ) where rownum > 0)

GSP代码：

<g:sortableColumn property="sortCandidateLastName" title="Sort By Candidate Last Name" />

但是当Hibernate尝试读取它时，它会抛出无效的列名：ResultSet.getInt(clazz_)

Answer 1

瞬态属性不会持久存在，因此无法编写按瞬态属性排序的查询。如果从查询中检索对象列表并希望按瞬态属性对它们进行排序，则必须在Groovy代码中执行此操作，例如。

// an example domain class with a transient property
class Book {
  private static Long SEQUENCE_GENERATOR = 0 

  String isbn
  String title
  Long sequence = ++SEQUENCE_GENERATOR  

  static transients = ['sequence']
}

// get a list of books from the DB and sort by the transient property 
def books = Book.list()
books.sort { it.sequence }

Answer 2

你无法对瞬态场进行排序。瞬态字段没有实际的数据库列！所以你的SQL总是会抛出一个错误！

Answer 3

我尝试使用jdbcTemplate并为我提供了所需的功能。

代码段：

GSP层：

<g:sortable property="sortCandidateLastName">
                    <g:message code="booking.alphabetical.label" default="Alphabetical(A-Z)" />
</g:sortable>

域层：

刚刚定义了一个瞬态属性：

static transients = ['sortCandidateLastName']

添加瞬态字段的原因：因此它不会抛出任何异常，例如缺少属性。

控制器层：

if(params.sort == "sortCandidateLastName" )
        {
            bookingCandList= bookingService.orderByCandidateLastName(params.max, params.order,params.offset.toInteger())//Booking.getSortCandidateLastName(params.max, params.order,params.offset.toInteger()) //


        }

服务层：

def jdbcTemplate

public List orderByCandidateLastName(Integer max, String sortOrder,Integer offset) {
           println  "Inside the getcandidateLastName ${max} :: offset ${offset}"
           def sortedList
           int minRow = offset
           int maxRow = offset+max
           String queryStr =   " select * from " + 
                                   " ( "+ 
                                   " select row_.* " + 
                                   " ,rownum rownum_ " +
                                   " from " +
                                   " ( " +
                                   " select * from booking b where b.item_id= 426 and b.marked_deleted='N' order by " +
                                   " (select c.cand_id from candidate c where b.cand_id = c.cand_id) ${sortOrder} "+
                                   "  ) row_ "+
                                   "where rownum <= ${maxRow}  " +
                                    ") " +
                                    "where rownum > ${minRow}"
           return jdbcTemplate.queryForList(queryStr)
       }

JDBC模板的配置：

// Place your Spring DSL code here
import org.springframework.jdbc.core.JdbcTemplate

beans = {
..........
    jdbcTemplate(JdbcTemplate) {
        dataSource = ref('dataSource')
     }
}

希望它有助于......

干杯