用Java查询数据库后返回一个数组 [英] Return an array after querying database in Java

问题描述

我必须查询MSSQL数据库，并且希望将查询结果作为Array或ArrayList返回.

I have to query a MSSQL database and I want the result of the query to returned as a Array or ArrayList.

我现在有一个这段代码，但是它给出了一个错误. 我已经连接到数据库，所以这不是问题.

I have a this code now, but it gives an error. I have a connection to the database so that's not the problem.

public ArrayList<Array> queryResult(String q) throws SQLException {

   ArrayList<Array> array = new ArrayList<>();
   Statement statement = this.getConnection().createStatement();
   ResultSet rs = statement.executeQuery(q);

   while(rs.next()) {

      Array n = rs.getArray(rs.getRow());
      System.out.println(n);
      array.add(n);

   }
   return array;
}

我收到以下错误

Exception in thread "main" com.microsoft.sqlserver.jdbc.SQLServerException: This operation is not supported.
      at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDriverError(SQLServerException.java:190)
      at com.microsoft.sqlserver.jdbc.SQLServerResultSet.NotImplemented(SQLServerResultSet.java:750)
      at com.microsoft.sqlserver.jdbc.SQLServerResultSet.getArray(SQLServerResultSet.java:2625)
      at server.Database.queryResult(Database.java:52)
      at server.Server.listen(Server.java:57)
      at server.Server.run(Server.java:34) at
      server.Server.<init>(Server.java:28) at
      server.Server.main(Server.java:94) Java Result: 1

推荐答案

getArray()将当前行的特定列的值作为数组返回.看到此内容- http://docs.oracle.com/javase/6/docs/api/java/sql/ResultSet.html#getArray%28int%29

getArray() returns the value of a particular column of the current row as an array. See this - http://docs.oracle.com/javase/6/docs/api/java/sql/ResultSet.html#getArray%28int%29

如果要将行值作为数组获取，则必须为诸如此类的事情编写代码.

If you want to get row values as array then you have to write code for that some thing like this.

while (rs.next()){
     java.util.ArrayList alRowData = new java.util.ArrayList();
     java.sql.ResultSetMetaData rsmd = rs.getMetaData();
     int numberOfColumns = rsmd.getColumnCount();
     for(int columnIndex = 1; columnIndex <= numberOfColumns; columnIndex ++){
          alRowData.add(rs.getObject(columnIndex));
     }
     System.out.println(alRowData);
}

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