我可以直接通过SQL select * from语句从java存储过程(oracle)获取结果吗？

在数据库上,我将有一个java存储过程/函数,当它被调用时返回一个多列,多行结果集.

我想直接通过select * from [table]语句访问这些​​结果.

所以java存储过程应该像表一样.

在MySQL中,以下应该是可能的(但不是java存储过程)：SELECT col1 FROM(EXEC proc1)

这可能在oracle中proc1是一个java存储过程吗？

解决方法:

This answer在不同的论坛可以帮到你.

查看消息底部的示例,了解如何从Java方法返回的集合中进行选择(也可能是Java存储过程).

以下是有关如何使用Java存储过程执行此操作的示例

1)创建DB对象以定义返回行的类型：

create type try_obj as object (

field_a number,

field_b varchar2(10)

)

/

create type try_obj_tab as table of try_obj

/

2)使用返回Collection的静态方法(GetSampleResult)在DB上创建Java类

create or replace and compile java source named QueryReturn as

import java.sql.*;

import java.util.*;

import oracle.jdbc.*;

import oracle.jdbc.pool.OracleDataSource;

import oracle.sql.*;

public class QueryReturn implements ORADataFactory,ORAData{

private NUMBER field1;

private CHAR field2;

public QueryReturn(OracleConnection conn,int n,String c) throws SQLException {

field1 = new NUMBER(n);

field2 = new CHAR(c,oracle.sql.CharacterSet.make(conn.getStructAttrCsId()));

}

public QueryReturn(NUMBER n, CHAR c) {

field1 = n;

field2 = c;

}

public QueryReturn(Object[] attributes) {

this(

(NUMBER) attributes[0],

(CHAR) attributes[1]

);

}

public QueryReturn(Datum d) throws SQLException {

this(((STRUCT) d).getOracleAttributes());

}

public ORAData create(Datum d, int sqlType) throws SQLException {

if (d == null)

return null;

else {

return new QueryReturn(d);

}

}

public STRUCT toSTRUCT(Connection conn) throws SQLException {

StructDescriptor sd =

StructDescriptor.createDescriptor("TRY_OBJ", conn);

Object [] attributes = { field1,field2 };

return new STRUCT(sd, conn, attributes);

}

public Datum toDatum(Connection conn) throws SQLException {

return toSTRUCT(conn);

}

public static ARRAY GetSampleResult() throws SQLException, ClassNotFoundException {

// initialize the connection

OracleConnection conn = null;

conn = (OracleConnection) (new oracle.jdbc.OracleDriver()).defaultConnection();

// create the return java array

// There will be two Rows

// 1 abc

// 2 dce

QueryReturn javaArray[] = {

new QueryReturn(conn,1,"abc"),

new QueryReturn(conn,2,"dce")

};

// Map the java class to the Oracle type

Map map = conn.getTypeMap();

map.put("TRY_OBJ", Class.forName("QueryReturn"));

ArrayDescriptor jTryObjArrayDesc = ArrayDescriptor.createDescriptor (

"TRY_OBJ_TAB",

conn

);

// create an Oracle collection on client side to use as parameter

ARRAY oracleCollection = new ARRAY(jTryObjArrayDesc,conn,javaArray);

return oracleCollection;

}

}

3)创建Wrap以在函数中使用Java存储过程

create or replace function GetSampleResult

return try_obj_tab

AS LANGUAGE JAVA

NAME 'QueryReturn.GetSampleResult() return oracle.sql.ARRAY';

4)显示结果

SQL> select *

2 from table(GetSampleResult())

3 /

FIELD_A FIELD_B

---------- ----------

1 abc

2 dce

SQL>

标签：java,sql,stored-procedures,oracle

来源： https://codeday.me/bug/20190621/1255122.html