Question

我正在尝试从我的应用程序中读取Oracle表信息。要获取表描述，我在我的应用程序上执行此查询：

        PreparedStatement preparedStatement = null;
        ResultSet resultSet = null;

        String sql = "SELECT DBMS_METADATA.GET_DDL('TABLE', 'CONTRACT_TABLE' ,'SCHEMA_NAME') FROM DUAL";
        preparedStatement = connection.prepareStatement(sql);
        resultSet = preparedStatement.executeQuery();

        if (resultSet.next()) {
            Clob clob = resultSet.getClob(1);
            String str = clob.getSubString(1, (int)clob.length());
            return str;             
        } else {
            throw new DBPlatformException("Object not available [Schema: "
                    + schema + "].[Name: " + objectName + "]!");
        }

以下是执行查询的代码块：

  CREATE TABLE "SCHEMA_NAME"."CONTRACT_TABLE" 
   (  "CONTRACT_ID" NUMBER, 
  "START_DATE" DATE, 
  "END_DATE" DATE
   ) PCTFREE 0 PCTUSED 0 INITRANS 1 MAXTRANS 255 
 COMPRESS FOR QUERY HIGH  NOLOGGING 
  STORAGE(
  BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
  TABLESPACE "TMP_SPACE" 
  PARTITION BY HASH ("CONTRACT_ID") 
 (PARTITION "P01" SEGMENT CREATION DEFERRED 
  TABLESPACE "TMP_SPACE" 
 COMPRESS FOR QUERY HIGH , 
 PARTITION "P02" SEGMENT CREATION DEFERRED 
  TABLESPACE "TMP_SPACE" 
 COMPRESS FOR QUERY HIGH , 
 PARTITION "P03" SEGMENT CREATION DEFERRED 
  TABLESPACE "TMP_SPACE" 
 COMPRESS FOR QUERY HIGH , 
 PARTITION "P04" SEGMENT CREATION DEFERRED 
  TABLESPACE "TMP_SPACE" 
 COMPRESS FOR QUERY HIGH , 
 PARTITION "P05" SEGMENT CREATION DEFERRED 
  TABLESPACE "TMP_SPACE" 
 COMPRESS FOR QUERY HIGH ) 
  PARALLEL 32

当我直接在数据库上运行sql时，我得到了这个结果：

  CREATE TABLE "SCHEMA_NAME"."CONTRACT_TABLE" 
   (  "CONTRACT_ID" NUMBER, 
  "START_DATE" DATE, 
  "END_DATE" DATE
   ) 
  PARTITION BY HASH ("CONTRACT_ID") 
 (PARTITION "P01" , 
 PARTITION "P02" , 
 PARTITION "P03" , 
 PARTITION "P04" , 
 PARTITION "P05" )

当我运行我的应用程序时，它会返回如下结果：

public static IEqualityComparer GetEqualityComparer(this NameObjectCollectionBase nameObjectCollection)
  {
  PropertyInfo propertyInfo = typeof(NameObjectCollectionBase).GetProperty("Comparer", BindingFlags.Instance | BindingFlags.NonPublic);
  return (IEqualityComparer)propertyInfo.GetValue(nameObjectCollection);
  }

public static IEqualityComparer<string> GetEqualityComparer(this NameValueCollection nameValueCollection)
  {
  return (IEqualityComparer<string>)((NameObjectCollectionBase)nameValueCollection).GetEqualityComparer();
  }

public static Dictionary<string, string> ToDictionary(this NameValueCollection nameValueCollection)
  {
  Dictionary<string, string> dictionary =
    nameValueCollection.AllKeys.ToDictionary(x => x, x => nameValueCollection[x], nameValueCollection.GetEqualityComparer());
  return dictionary;
  }

我的应用程序返回的结果信息较少。我需要知道表是否并行，但我的应用程序无法向我提供该信息。

我试图找出查询结果不同的原因以及如何检索并行信息。

Answer 1

尝试执行

begin
  DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'STORAGE',TRUE);
  DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'TABLESPACE',TRUE);
  DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM,'SEGMENT_ATTRIBUTES',TRUE);
end;
/

在java中声明并查看结果是否发生变化之前

。

Prepared Statement不会检索sql的确切结果

1 个答案: